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En este trabajo se construyó y optimizó un sistema de gasificación a escala banco de residuos biomásicos (aserrín de pino). El sistema consta de una unidad de alimentación (tolva y tornillo), un reactor autotérmico de lecho fluidizado y acondicionamiento de gases (ciclón y enfriamiento). En el reactor se evaluaron 2 catalizadores de bajo costo: un mineral natural (dolomita) y residuo de pirólisis comparados con un sólido inerte (arena). Los catalizadores y la biomasa fueron caracterizados por diferentes técnicas: ICP, BET, TGA, CHONS, entre otras. En la optimización del proceso se estudiaron diferentes parámetros: tamaño de partícula de biomasa, flujo másico de alimentación, agentes gasificante y perfiles de temperatura. Los ensayos mostraron un óptimo funcionamiento con un tamaño de biomasa en el rango de 0.50-0.85 mm, un flujo másico de alimentación de 0.840 kg/h y una relación de equivalencia entre mezcla de agentes gasificantes (aire y/o vapor de agua) y alimentación de 0.35-0.45 con temperaturas de equilibrio de 650 y 750ºC, respectivamente. Los catalizadores evaluados tuvieron una reducción de alquitrán entre 10-45% comparado con el inerte y valores superiores en la relación H2:CO y LHV. Los resultados mostraron que el sistema de gasificación autotérmico a escala banco construido, permite la transformación de la biomasa utilizando catalizadores de bajo/nulo costo, lo que lo hace atractivo desde el punto de vista ambiental y económico.

Pyrolysis gasoline (PyGas) is an unstable byproduct of the pyrolysis of naphtha and other hydrocarbons for the production of olefins. PyGas is stabilized by hydrogenation at mild conditions. The hydrogenation of styrene to ethylbenzene is considered a model test reaction for studying the selectivity of the catalysts because it has the slowest rate of conversion. The catalytic activity and selectivity of two bimetallic co-impregnated Pd–Ni catalysts supported on γ-alumina were assessed and compared to those of a commercial monometallic Pd catalyst (AXENS LD265). The laboratory-prepared catalysts had different metal content and Pd:Ni atomic ratios (1:1 and 1:7). Catalytic tests of selective hydrogenation of styrene to ethylbenzene were made in a batch stirred tank reactor and in a continuous fixed bed trickle bed reactor. The sulfur resistance of the bimetallic catalysts in semicontinuous condition, was assessed by means of the same operational conditions using thiophene as a model poison compound. The support, Pd–Ni co-impregnated catalysts and LD265 commercial catalysts were further characterized by N2 chemisorption, EPMA, OM, ICP elemental analysis, temperature programmed reduction, XPS and X-Ray diffraction. The results indicated the presence of different metal species: Pd0, Pdδ+, Ni0 and NiO. The lab-prepared bimetallic catalysts were found to be active for the selective hydrogenation of styrene (both in the batch and continuous system). During the continuous evaluations, the commercial LD265 catalyst had an intermediate activity level that lied between the values corresponding to the Pd–Ni bimetallic catalysts: PdNi(1:1) ≫ LD265 > PdNi(1:7). During the poison free semicontinuous evaluations, the pattern of conversion as a function of contact time of co-impregnated Pd–Ni catalysts are quite similar to that of commercial LD265 catalyst, though the catalytic activity is slightly better for PdNi(1:1). After 90 min of contact time the order of conversion was: PdNi(1:1) > LD265 > PdNi(1:7). On the other hand, during the poison semicontinuous tests (with 300 pp of thiophene), the initial reaction rates of the co-impregnated catalysts decreased, pointing a poisoning of the active sites by thiophene. PdNi(1:1) had higher initial reaction rate than PdNi(1:7) during poison free or poisoned in both conditions. PdNi(1:7) was more sulfur resistant than PdNi(1:1). The higher activity of the PdNi(1:1) catalyst was attributed to the presence of Pd0 and Pdn+/Nim+ species that favored respectively, the homolytic cleavage of the H–H bond and the adsorption of styrene. The higher sulfur resistance of the PdNi(1:7) catalyst would be associated with the higher Cl/Al surface atomic ratio in this catalyst (electronic effect) and the presence of electrodeficient species of Pd (Pdxδ+OyClz) that prevented the adsorption of thiophene by steric hindrance (geometrical effect of the large species) or by electronic effects. The authors are thankful to the Consejo Nacional de Investigaciones Científicas y Técnicas (National Council for Scientific and Technological Research, CONICET, Argentina), the Agencia Nacional de Promoción Científica y Tecnológica (National Agency of Scientific and Technological Promotion, ANPCyT, Argentina): PICT 2016-1453, PICT 2017-1250, and the Universidad Nacional del Litoral (National University of the Litoral): CAI+D 2016 N° 50420150100028LI for the financial support.

The selective hydrogenation of oleic acid to oleyl alcohol over a Rh(1 wt%)–Sn(4 wt%)–B/Al2O3 catalyst was studied. A comprehensive set of experimental data was used for elucidating the reaction mechanism. In the range of reaction conditions of this work, the optimal conditions found were 290 °C and 2 MPa, with a yield of 82–83% of oleyl alcohol. Kinetic models were written which considered the whole network of reactions taking place: double bond hydrogenation, acid hydrogenation to alcohol, and esterification of acids and alcohols. Different combinations of elementary steps led to the formulation of a big number of models. Models posing the surface reactions as rate-limiting fitted the data better. Adsorption of the acids, the alcohols or hydrogen was not rate-limiting. The best-fit model had the following hypotheses: (i) only one kind of adsorption site is needed for all species and reactions; (ii) H2 is dissociatively adsorbed; (iii) fatty molecules are adsorbed on only one site; (iv) pairwise insertion of H to fatty molecules is the rate-limiting step; (v) reduction of the carboxylate group occurs via an aldehyde intermediate that is subsequently hydrogenated to the corresponding alcohol; (vii) hydrogen and oleic acid are the main adsorbates; (vii) heavy esters are formed but do not contribute as intermediates of the main mechanism.

Fil: Busto, Mariana. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet - Santa Fe. Instituto de Investigaciones en Catalisis y Petroquimica "Ing. Jose Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catalisis y Petroquimica "Ing. Jose Miguel Parera"; Argentina

Deacidification of a vegetable oil by extraction and regeneration of the solvent by means of adsorption was studied. This novel approach to solvent regeneration is posed as an alternative to distillation in systems with high solvent-to-feed ratios in which evaporation of large solvent amounts is economically unattractive. An example was chosen of deacidification of sunflower oil by extraction with methanol and regeneration of the alcohol by adsorption over activated carbon. The example has application for the biodiesel and technical oils industries. The results showed that high temperatures of extraction increased the acid?methanol partition coefficient but also the mutual solubility of oil and methanol. One extraction stage with a solvent-to feed ratio of 20 (vol:vol) reduced the oil acidity to acceptable values. Regeneration of the extract by adsorption over activated carbon was found to be efficient. For regenerating the bed, elution with a hot solvent was studied. Adsorbent regeneration was completed to a high degree, with elution temperature being the most important variable. For exploring the influence of process variables on the performance of extraction-adsorption, simulation was used. Necessary parameters for mass transfer and adsorption were fitted from breakthrough tests with the aid of a linear driving force model. Simulation results confirmed the viability of the proposed process as an alternative for solvent regeneration of extraction units. Fil: Busto, Mariana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentina Fil: Vera, Carlos Roman. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentina

Low loaded W-Pd/Alumina are relatively novel catalysts for performing the selective hydrogenation of alkynes, but there is scarce information on the working mechanism. This work studies the kinetics of the selective hydrogenation of 3-hexyne to (Z)-3-hexene over a low loaded W-Pd/Alumina catalyst. Runs at different mild reaction conditions were used for fitting a set of Langmuir-Hinshelwood models. Semihydrogenation was the prevailing reaction path, leading selectively to (Z)-3-hexene > 95%, as with classical Lindlar catalysts. Smaller amounts of (E)-3-hexene and negligible of n-hexane were detected. When considering a pseudo-homogeneous model, approximate orders in 3-hexyne and hydrogen were (2.5) and (-2.2), respectively. The latter value pointed to an important role of hydrogen chemisorption. Twelve kinetic models were fitted to the experimental data. A normal dissociative adsorption of hydrogen could not account for the high order in hydrogen, hence the adsorption of non-dissociated molecular hydrogen was also taken into account. Best fit model was the one considering adsorption of 3-hexyne as rate-limiting step, with molecular hydrogen acting as a competitor over Pdn+ sites, and with hydrogen being dissociated over other different sites: Pddˉ. Fil: Betti, Carolina Paola. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentina Fil: Torres, Gerardo Carlos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentina Fil: Maccarrone, María Juliana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentina Fil: Lederhos, Cecilia Rosa. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentina Fil: Quiroga, Monica Esther. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentina Fil: Yori, Juan Carlos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentina Fil: Vera, Carlos Roman. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentina

The possibility of regenerating the solvent of extraction units by cyclic adsorption was analyzed. This combination seems convenient when extraction is performed with a high solvent-to-impurity ratio, making other choices of solvent regeneration, typically distillation, unattractive. To our knowledge, the proposed regeneration scheme has not been considered before in the open literature. Basic relations were developed for continuous and discontinuous extraction/adsorption combinations. One example, deacidification of plant oil with alcohol, was studied in detail using separate experiments for measuring process parameters and simulation for predicting performance at different conditions. An activated carbon adsorbent was regenerated by thermal swing, making cyclic operation possible. When extracting the acid with methanol in a spray column, feed = 4 L min -1 , solvent = 80 L min -1 , feed impurity level 140 mmol L -1 , and extract concentration 7.6 mmol L -1 , the raffinate reaches a purity of 1.2 mmol L -1 , the solvent being regenerated cyclically in the adsorber (364 kg) to an average of 0.7 mmol L -1 . Regeneration of the solvent by cyclic adsorption had a low heat duty. Values of 174 kJ per litre of solvent compared well with the high values for vaporization of the whole extract phase (1011 kJ L -1 ). Fil: Busto, Mariana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentina Fil: Tarifa, Enrique Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentina Fil: Vera, Carlos Roman. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentina

Fil: Manuale, Debora Laura. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet - Santa Fe. Instituto de Investigaciones en Catalisis y Petroquimica "Ing. Jose Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catalisis y Petroquimica "Ing. Jose Miguel Parera"; Argentina

The possibility of directly feeding the extract of a liquid-liquid extraction unit to a chemical reactor is analyzed. An example of extraction and noncatalytic esterification of naphthenic acids from acid petroleum crudes is used. Methanol is used both as a solvent and as a reactant. Separate tests of extraction and reaction are performed, and the performance of an integrated process is deduced by computer simulation. Thermodynamic and kinetic parameters for the extraction of naphthenic acids from an acid crude were determined. A partition coefficient of m = 0.66 at 60 °C between the alcoholic and petroleum phases was found. Three successive batch extractions with a 1:1 v/v ratio reduced the acidity from 4.3 to about 1.1 mgKOH g-1. Naphthenic acid concentrates were reacted with supercritical methanol in a batch reactor at high temperatures (280 °C), yielding naphthenic esters. Reaction of 1-2 h with methanol-to-oil molar ratios of 3-6 yielded 92-96% conversion because of a relatively low value of the equilibrium constant. Total conversion could, however, be achieved with the highly diluted extracts. Simulations were run using three countercurrent mixer-settlers and a noncatalytic reactor. The results indicated that extraction/supercritical esterification is a convenient pretreatment step of acidic feedstocks because of its simplicity, the good quality of the deacidified feedstock (acidity

The hydrogenation of α-diketones yields α-hydroxyketones or vic-diols, both compounds of great interest in fine chemistry.The reaction tests were the liquid phase hydrogenation of 2,3-butanedione and 2,3-pentanedione at mild conditions. Theobjectives of this work were evaluating the effect over the activity and selectivity of: (a) different transition metallic phasebased catalysts supported on activated carbon, (b) the symmetry of the reactants and (c) solvents. The physicochemicalcharacterization of the catalysts was carried out by ICP, XRD, TEM, N2adsorption and XPS. The keto-enol equilibrium ofdiketones was studied by 1H-NMR. All the catalysts were active in both reactions. In terms of activity, Pt and Rh were thebest active phases. For both reactants the highest selectivity towards hydroxyketones were achieved with Pd, while Ru wasthe most selective towards the diol. Both the activity and selectivity followed similar patterns in the hydrogenation of bothdiketones. The greater activity of Pt was attributed to the high dispersion of the active metal phase in this catalyst and thehigh efficiency of Pt for C = O bond reduction. The high selectivity of the Pd catalysts towards the intermediate product wasattributed to many effects: (i) a lower interaction of the hydroxyketone with the active site as compared to the diketone, (ii)the easy reducibility of the C = C double bond on Pd, provided by the keto-enol tautomerism of diketones. Fil: Carrara, Nicolás Ricardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentina Fil: Badano, Juan Manuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentina Fil: Vaillard, Santiago Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnológico para la Industria Química; Argentina Fil: Vera, Carlos Roman. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentina Fil: Quiroga, Monica Esther. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentina

The effect of noble metal catalysts supported on an ionic exchange resin for the enantioselective hydrogenation of ethyl pyruvate to ethyl lactate was studied. High activity and moderate enantioselectivity levels were obtained. Pt was the best enantioselective metallic phase, followed by Pd and Au; Rh was the less enantioselective metallic phase. The effect of the active site was evaluated for the most enantioselective catalyst: 2Pt-WA30. A novel method for sintering the Pt metal particles by nitriles reduction was used, and a controlled migration of the metal particles to the surface layers was observed. There existed an optimal particle size that maximized the enantiomeric excess, corresponding to 24 h sintering. The hydrogenation of ethyl pyruvate to ethyl lactate was found to be structure-sensitive and the importance of the metal particle size for the adsorption of the chiral modifier was proved.Besides, two different chirality induction methods were tried for the 2Pt-WA30 catalyst: i) the addition of the Chiral Modifier to the reaction media, or ii) the modification of the catalyst in a swelling medium prior to the reaction in order to encapsulate the Chiral Modifier. Lower activity but higher enantioselectivity levels were obtained with method (ii).Finally, the reuse of the catalysts was also assessed by means of consecutive reaction tests. Fil: Carrara, Nicolás Ricardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentina Fil: Badano, Juan Manuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentina Fil: Mendow, Gustavo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentina Fil: Ruiz, Doris. Universidad de Chile; Chile Fil: Vera, Carlos Roman. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentina Fil: Quiroga, Monica Esther. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentina

The influence of the kind of support (Al2O3, SiO2, and TiO2) on the catalytic activity and selectivity of Ru−Sn−Bcatalysts for the hydrogenation of methyl oleate to oleyl alcohol was studied. The results show that the most active and selectivecatalyst for producing oleyl alcohol is Ru(1%)−Sn(2%)−B/Al2O3. This was attributed to the catalyst having a favorable surfaceSn/Ru ratio (∼2). The SiO2-supported Ru−Sn−B catalyst had a good activity and hydrogenated both C═C double bonds andthe C═O group, thus producing stearyl alcohol with a high yield. It however deactivated, to a great extent, its final conversionbeing lower than that of the bimetallic catalysts supported on Al2O3 and TiO2. The TiO2-supported catalyst had a high selectivityto saturated methyl esters because it hydrogenated C═C double bonds but had little activity for hydrogenation of the C═Ogroup Fil: Sánchez, María Amparo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; Argentina Fil: Mazzieri, Vanina Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; Argentina Fil: Vicerich, Maria Ana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; Argentina Fil: Vera, Carlos Roman. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; Argentina Fil: Pieck, Carlos Luis. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; Argentina

The influence of the kind of metal precursor and the sequence of impregnation on the properties of Pd-Ni catalysts was evaluated during the test reaction of selective hydrogenation of styrene to ethylbenzene by means of physicochemical characterization. The focus was put on the final hydrogenating activity and the resistance to deactivation by sulfided compounds (thiophene). The used techniques of characterization were ICP, XPS, XDR, TPR, CO chemisorption and TEM. XPS results indicated the presence of different Pd species: Pdδ-, Pdº and Pdδ+. In the case of the Ni containing catalysts, Niº and NiO species were also detected. These palladium and nickel species would be responsables of the variation of activity and sulfurresistance of the catalysts. NiClPd catalysts had a higher resistance to deactivation by sulfur poisoning. This was associated to a higher concentration of Pdη+ClxOy species that would prevent the adsorption of thiophene by both steric and electronic effects. It could also be due to the lower concentration of Pdº and Niº on these catalysts, as compared to those shown by the PdNiCl catalysts. Both the Pdº and Niº species are more prone to poisoning because of their higher electronic availability.

New catalysts of Pt, PtNi, PtCo, and NiCo supported on Al2O3 were developed for producing hydrogen by aqueous phase reforming (APR) of oxygenated hydrocarbons. The urea matrix combustion technique was used for loading the metal on the support in order to improve several aspects: increase both the metal-support interaction and the metal dispersion and decrease the metal load. The catalysts were characterized by MS/ICP, N2 adsorption, XRD, TPR, CO chemisorption, and the test of cyclohexane dehydrogenation (CHD). The APR of a solution of 10% mass ethylene glycol (EG), performed in a tubular fixed bed reactor at 498 K, 22 bar, WHSV = 2.3 h-1, was used as the main reaction test. After 10 h on-stream, the catalysts prepared by UMC had better hydrogen yield and catalytic stability than common catalysts prepared by IWI. The UMC/IWI H2 yield ratio was 23.5/15.2 for Pt, 24.0/17.0 for PtCo, 26.6/21.0 for PtNi, and 8.0/3.9 for NiCo. Ni or Co addition to Pt increased the carbon conversion while keeping the H2 turnover high. Cobalt also improves stability. Reports of several authors were revised for a comparison. The analysis indicated that the developed catalysts are a viable and cheaper alternative for H2 production from a renewable resource. Fil: Dosso, Liza Ainalen. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentina Fil: Vera, Carlos Roman. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentina Fil: Grau, Javier Mario. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentina

As assessment was made of the influence of the crystal structure on the activity of SO42−–ZrO2 catalysts for the acid-catalyzed reactions of sucrose inversion and the esterification of fatty acids with glycerol. Purely monoclinic or purely tetragonal SO42−–ZrO2 catalysts were synthesized by sulfation with 1 M sulfuric acid of different ZrO2 starting materials of defined crystal phase. The final catalysts were obtained by calcination at 400 °C, a relatively mild temperature for this kind of materials. Structural and morphological characterization tests showed that the crystal phase of zirconia had an influence on the properties of the sulfated zirconia catalysts. Monoclinic and tetragonal catalysts had different acidities and also different levels of activity in the reactions. Better results in the sucrose inversion tests were obtained using tetragonal phase catalysts while monoclinic phase materials were better catalysts for glycerol esterification. The catalysts were further characterized by Fourier transform infrared spectroscopy (FT-IR), X-ray powder diffraction (XRD), transmission electron microscope (TEM), X-ray photoelectron spectroscopy (XPS) and nitrogen physisorption. The acidity was measured by amine titration using Hammett indicators and FT-IR absorption of adsorbed pyridine. Fil: Miranda M., Cristian David. Universidad del Cauca; Colombia Fil: Ramírez, Alfonso E.. Universidad del Cauca; Colombia Fil: Gaona Jurado, Sonia. Universidad del Cauca; Colombia Fil: Vera, Carlos Roman. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; Argentina

Two organic–inorganic mixed phase supports were prepared, comprising an alumina filler and polymers of different chemical nature. Four low loaded Pd catalysts were prepared. Good activities and selectivities were obtained during the hydrogenations of styrene, 1-heptyne and 2,3-butanedione. The catalysts were found to have excellent mechanical properties and could be used in applications needing high attrition resistance and crushing strength. In this sense, processes for fine chemicals using slurry reactors or processes for commodities using long packed beds could advantageously use them. Fil: Carrara, Nicolás Ricardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Santa Fe. Instituto de Investigaciones En Catálisis y Petroquímica; Argentina Fil: Badano, Juan Manuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Santa Fe. Instituto de Investigaciones En Catálisis y Petroquímica; Argentina Fil: Betti, Carolina Paola. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Santa Fe. Instituto de Investigaciones En Catálisis y Petroquímica; Argentina Fil: Lederhos, Cecilia Rosa. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Santa Fe. Instituto de Investigaciones En Catálisis y Petroquímica; Argentina Fil: Rintoul, Ignacio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Santa Fe. Instituto de Desarrollo Tecnológico Para la Industria Química (i); Argentina. Universidad Nacional del Litoral. Facultad de Ingeniería Química; Argentina Fil: Coloma Pascual, Fernando. Universidad de Alicante; España Fil: Vera, Carlos Roman. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Santa Fe. Instituto de Investigaciones En Catálisis y Petroquímica; Argentina. Universidad Nacional del Litoral. Facultad de Ingeniería Química; Argentina Fil: Quiroga, Monica Esther. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Santa Fe. Instituto de Investigaciones En Catálisis y Petroquímica; Argentina. Universidad Nacional del Litoral. Facultad de Ingeniería Química; Argentina

Two composite supports with a mixed inorganic–organic structure were synthesized: BTAl and UTAl. Hydrophilic–hydrophobic dual properties of the supports were suitable for preparing egg-shell-supported metal catalysts for selective hydrogenation reactions. The catalysts were characterized by ICP, XRD, OM, TEM, EPMA, XPS and TGA. Their mechanical resistance was assessed. Activity and selectivity were tested with the hydrogenation of 2,3-butanedione (diacetyl) to 3-hydroxy-2-butanoneacetoin (acetoin). The same order of increasing metal particle size was found for the two tested supports: Pt < Ru < Pd. The XPS analysis showed that the metal/composite catalysts reduced in H2 at 503 K had two kinds of active sites: reduced (Me°) and electron-deficient (Me+). It was rationalized that the hydrogen bond cleavage was performed on the Me° active sites, while reactant adsorption occurred on the Me+ sites. The differences in activity and selectivity between the composite catalysts were attributed to electronic effects on the different metals and to different adsorptive properties of the different polymers. The high selectivity to acetoin was attributed to the preferential adsorption of diacetyl as compared to the adsorption of acetoin. The BTAl catalysts were slightly more active and selective than the UTAl ones. This was attributed to electronic effects caused by remnant organic groups on the composite supports (urethane or biphenyl on UTAl or BTAl, respectively). Pd-BTAl was the most active and selective catalyst, a fact related to electronic effects of both palladium and the support. Fil: Carrara, Nicolás Ricardo. Universidad Tecnológica Nacional; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentina Fil: Badano, Juan Manuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentina. Universidad Nacional del Litoral; Argentina Fil: Coloma Pascual, F.. Universidad de Alicante; España Fil: Vera, Carlos Roman. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentina. Universidad Nacional del Litoral; Argentina Fil: Quiroga, Monica Esther. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentina. Universidad Nacional del Litoral; Argentina

A comparison of Pt-M/Al2O3 catalysts (M = Ni, Co, none) for the aqueous phase reforming (APR) of different polyols that can be obtained from glucose degradation was made. A standard monometallic Pt/Al2O3 catalyst was prepared by incipient wetness impregnation (IWI) of platinum on an alumina support. The bimetallic catalysts had Ni or Co promoters incorporated by the urea matrix combustion method (UCM) and Pt by IWI technique (PtNi and PtCo catalysts).The catalysts were characterized by ICP/MS analysis, CO/chemisorption, TPR, XPS, SEM-EPMA and XRD. The catalytic activity was assessed with the tests of APR of an aqueous solution of 10 %wt of ethylene glycol (EG), glycerol (Gly) or sorbitol (Sorb), in a tubular fixed bed reactor at 498 K, 2.2 MPa, WHSV = 2.3-2.5 h-1, 3 cm3min-1 He carrier. Monitored variables were: conversion to carbon product in the gas phase, hydrogen and methane yield, selectivities, TOF and coke content on the spent catalysts.PtNi and PtCo catalysts had better hydrogen yield and stability during the experiments than the un-promoted Pt catalyst, (H2 yield = 24.4, 21.2 and 15% for PtNi, 17.9 and 15.1 for PtCo and 13.7, 10.8 and 7.5% for Pt after 8 h on stream in APR of EG, Gly or Sorb solution, respectively). Especially PtNi showed excellent yield and selectivity to hydrogen and a good stability, steadily generating hydrogen for long times. Co addition mainly helped in keeping low levels of coke and a low selectivity to methane. Fil: Dosso, Liza Ainalen. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; Argentina Fil: Vera, Carlos Roman. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; Argentina Fil: Grau, Javier Mario. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; Argentina

In this paper a simple biodiesel purification method consisting of one single stage treatment with silica as adsorbent is described. The presented method seems a solution for biodiesel refining saving water, money and process time. The treatment is made under conditions of vacuum (0.2 bar) and mild temperature (65–90 °C). The method allows for the removal of the excess of methanol and water (present in the crude biodiesel and adsorbed on the adsorbent material) simultaneously with the adsorption of the impurities. Silica Trisyl 3000 retains 23% of its weight when the process is conducted at atmospheric pressure and nearly 235% when performed under vacuum conditions. This greatly improves the utilization of the adsorbent and reduces the cost of the process. Under these conditions, the silica behaves as a non-selective adsorbent of high capacity that is able to adsorb different types of impurities, which makes it an excellent adsorbent to purify biodiesel. On the other hand, the adsorption phenomenon is not limited to the formation of a theoretical “monolayer” of adsorbed impurities; it is more complex and includes the formation of multiple layers. Fil: Manuale, Débora Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; Argentina. Universidad Nacional del Litoral. Facultad de Ingeniería Química; Argentina Fil: Greco, Elisabet. Universidad Nacional del Litoral. Facultad de Ingeniería Química; Argentina Fil: Clementz, Adriana Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; Argentina Fil: Torres, Gerardo Carlos. Universidad Nacional del Litoral. Facultad de Ingeniería Química; Argentina Fil: Vera, Carlos Roman. Universidad Nacional del Litoral. Facultad de Ingeniería Química; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; Argentina Fil: Yori, Juan Carlos. Universidad Nacional del Litoral. Facultad de Ingeniería Química; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; Argentina

Adsorbents of granular activated carbon doped with iron (Fe/GAC) were synthesized in the laboratory and their capacity for removal of arsenic species was measured by means of techniques of equilibrium adsorption and breakthrough curves. These data were obtained at room temperature and normal pH conditions. The materials were further characterized to determine their chemical composition and texture (specific surface, pore volume distribution). It was found that the adsorbents with 10%, 20% and 30% Fe had a great capacity for arsenic adsorption, showing uptake values of 2000-3500 μg of As per gram of Fe/GAC filter material. Doping with Fe increases the As adsorption capacity of granular activated carbon and the maximum capacity of adsorption is obtained with 10% Fe loading. Higher Fe contents decrease the capacity for arsenic removal. This was related to the decreased pore volume and pore size of the adsorbents with high Fe content. A decrease of surface accessibility due to pore plugging and a higher intraparticle diffusion resistance in the high loaded adsorbents would shift the point of bed breakthrough to lower values of eluted volume. Fil: Sigrist, Mirna Edit. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Programa de Investigación y Análisis de Residuos y Contaminantes Químicos; Argentina Fil: Brusa, Lucila. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Programa de Investigación y Análisis de Residuos y Contaminantes Químicos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; Argentina Fil: Beldomenico, Horacio Ramon. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Programa de Investigación y Análisis de Residuos y Contaminantes Químicos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; Argentina Fil: Dosso, Liza Ainalen. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; Argentina Fil: Tsendra, Oksana. National Academy of Sciences. Chuiko Institute of Surface Chemistry; Ucrania Fil: Gonzalez, Monica Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; Argentina Fil: Pieck, Carlos Luis. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; Argentina Fil: Vera, Carlos Roman. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; Argentina

The reutilization of agroindustrial wastes for the production of new products is an attractive option for reducing environmental pollution, generating value-added products and decreasing costs. Slaughterhouse discard bovine bone, brewery discard yeast and carrot discards from the Santa Fe province (Argentina) were used for producing ethanol. Bovine bone and yeast provided the support and active phase for fermentation biocatalysts while carrot discards were a sugar source. Discard bovine bone was collected directly from a slaughterhouse and then subjected to extraction with acetone for removing lipids and blood traces. Both uncalcined and heat-treated bovine bone (calcined for 2 h at 400, 600 and 800 °C) were studied. Uncalcined bovine bone had a suitable pore structure for yeast immobilization and a suitable mechanical resistance for being used in stirred tanks. Two different strains of Saccharomyces cerevisiae were immobilized and tested. One was a brewery yeast discarded from a local beer brewery and the other one a commercial yeast. The biocatalysts thus obtained were subjected to a thermal treatment at 35 °C for 72 h in order to dehydrate cells and form adhesins. The activity of the biocatalysts was tested in the fermentation of carrot discards. The maximum concentration of the obtained ethanol was 11.98 g L−1. It was possible to reuse the biocatalysts for 11 reaction cycles. The possibility of regenerating the biocatalyst bone support by ultrasound is an advantage of this kind of material in comparison to common gel supports.

The elimination of free fatty acids (FFAs) and water from biodiesel is usually performed in industrial practice using different units for neutralization with caustic, washing, and drying of the fuel. Adjustment of the acidity, however, can be performed in only one operation using bleaching tanks and commercial adsorbents. The current article explores the use of several adsorbents (TriSyl commercial silicas, diatomaceous earth, impregnated activated carbon) and varying process conditions (temperatures, vacuum levels, residence times) for the removal of FFAs from commercial biodiesel fuel. It was found that silica TriSyl 3000 was the best performing adsorbent, with a capacity for the removal of FFAs of about 1 g g–1 at high values of biodiesel acidity. The two factors influencing the capacity for FFA adsorption are the temperature and the silica residual water content. The latter depends on both the temperature and especially the vacuum level of the pretreatment step. The FFA uptakes over TriSyl silicas in a vacuum were 3–4 times larger than that obtained at atmospheric pressure. The adsorption curves were linear in the range of interest (0–2% acidity), and hence, Henry’s law could be used. Values of the Henry’s constant of 30.0–47.6 (dimensionless) were measured for TriSyl 3000 silica, along with a heat of adsorption of −5.7 kcal mol–1. From the kinetic point of view, FFA adsorption is rather slow despite the small diameter of the particles used. The system was found to be highly constrained either by intrinsic slow kinetics or by intraparticle mass-transfer resistance. An unfavorable adsorption equilibrium leading to high adsorbent consumption in one-bleacher operation suggested the use of a countercurrent liquid–solid mode of operation with multiple bleachers. Simulation of two and three serial bleachers working in countercurrent mode revealed that savings greater than 60% can be obtained by using three bleachers operating in countercurrent flow. Fil: Manuale, Débora Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentina Fil: Torres, Gerardo Carlos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentina Fil: Badano, Juan Manuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentina Fil: Vera, Carlos Roman. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentina Fil: Yori, Juan Carlos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentina

BACKGROUND Heterogeneous hydrogenation catalysts for fine chemical synthesis are a convenient alternative to homogeneous catalysts because of the ease of separation and reuse. In order to be good catalysts they must have high activity and selectivity and good mechanical properties. Appropriate kinetic models should also be available for reactor design. Novel composite supported Pd catalysts were synthesized and tested in the liquid-phase selective hydrogenation of 2,3-butanedione to 3-hydroxy-2-butanone (acetoin). The composite support comprised a mixture of an organic polymer and γ-Al2O3. The support and the Pd catalyst were further characterized by XRD, SEM, EMPA and XPS spectroscopy. Catalytic tests at various conditions were performed in order to elucidate the kinetics of the system. RESULTS The composite had better mechanical properties (resistance to radial and axial compression) in comparison with other commercial supports. Good activity and high selectivity to acetoin, a product of partial hydrogenation, were obtained at different reaction conditions. A Langmuir–Hinshelwood chemical rate expression useful for reactor design was regressed from the kinetic data. CONCLUSIONS The experimental results could be explained by a Horiuti–Polanyi mechanism in which the addition of an H atom to the carbonyl group in the adsorbed state is the rate limiting step. © 2013 Society of Chemical Industry

Pt-Ir/HY and Pt-Mg-Ir/Al2O3 catalysts were studied and tested in the reaction of ring opening of decalin.The acidity of the alumina support was modified by addition of 3% Mg and the acidity of the zeolite by ion exchange with NH4Cl. The Pt content of the catalysts was fixed at 1% (mass basis) while the Ir content was adjusted between 0.1 and 0.6%. The catalysts were characterized by temperature programmed reduction, temperature programmed desorption of pyridine and FTIR of adsorbed CO. They were further tested with the reactions of cyclohexane dehydrogenation, cyclopentane hydrogenolysis and n-C5 isomerization.It was found that the Pt-Ir/HY catalyst was substantially more acid than Pt-Mg-Ir/Al2O3. Increasing the Ir content produced an increase of the hydrogenolytic activity and a decrease of the dehydrogenating activity of both catalysts. The n-pentane isomerization reaction results revealed that in the case of the alumina catalyst increasing the Ir content promoted both the catalyst stability and the cracking selectivity to C5 isomers. The opposite was found for the Pt-Ir/HY zeolite catalysts. The zeolite supported Pt-Ir catalysts performed better for decalin ring opening than those supported on alumina. Higher Ir content favored the formation of ring-opening products in all cases. Fil: D'ippolito, Silvana Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones En Catalisis y Petroquímica "ing. Jose Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones En Catalisis y Petroquímica "ing. Jose Miguel Parera"; Argentina Fil: Gutierrez, Laura Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones En Catalisis y Petroquímica "ing. Jose Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones En Catalisis y Petroquímica "ing. Jose Miguel Parera"; Argentina Fil: Vera, Carlos Roman. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones En Catalisis y Petroquímica "ing. Jose Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones En Catalisis y Petroquímica "ing. Jose Miguel Parera"; Argentina Fil: Pieck, Carlos Luis. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones En Catalisis y Petroquímica "ing. Jose Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones En Catalisis y Petroquímica "ing. Jose Miguel Parera"; Argentina

The sulfur resistance of low-loaded monometallic Pt catalysts and bimetallic Pt-W catalysts during the partial selective hydrogenation of styrene, a model compound of PYGAS streams, was studied. The effect of metal impregnation sequence on the activity and selectivity was also evaluated. Catalysts were characterized by ICP, TPR, XRD and XPS techniques. Catalytic tests with sulfur-free and sulfur-doped feeds were performed.All catalysts showed high selectivities (> 98%) to ethylbenzene. Activity differences between the catalysts were mainly attributed to electronic effects due to the presence of different electron-rich species of Pt0, and electron-deficient species of Ptä+. Pt0 promotes the cleavage of H2 while Ptä+ the adsorption of styrene. The catalyst successively impregnated with W and Pt (WPt/Al) was more active and sulfur resistant than the catalyst prepared with an inverse impregnation order (PtW/Al). The higher poison resistance of WPt/Al was attributed to the presence of chloride that inhibits the adsorption of thiophene because of steric and electronic effects. On the other hand, the lower concentration of chloride and a high concentration of Pt0 electron-rich sites (with low BE values) could contribute to the poisoning, as these species would act as electron donor sites, providing available electrons to be bond with the S atom of thiophene. Both effects would promote a strong adsorption of thiophene and thus an enhanced blocking of the catalyst active sites. Fil: Betti, Carolina Paola. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentina Fil: Badano, Juan Manuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentina Fil: Rivas, Ivana Lorena. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentina Fil: Mazzieri, Vanina Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentina Fil: Maccarrone, María Juliana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentina Fil: Coloma Pascual, Fernando. Universidad de Alicante. Facultad de Ciencias; España Fil: Vera, Carlos Roman. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentina Fil: Quiroga, Monica Esther. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentina

Isomerization-cracking of long paraffins to produce octane enhancers for the gasoline pool is a complex refinery operation that needs simultaneous adjustment of the molecular size of the feed (cracking) and skeletal branching (isomerization). As both reactions are acid-catalyzed it is very difficult to adjust the acidity distribution of a single catalyst to have a proper balance. In this work the used catalyst is a mixture of an isomerization catalyst (Pt/WO 3 –ZrO 2 ) (PtWZ) and a cracking catalyst (Pt/SO 4 2− –ZrO 2 ) (PtSZ), working at the same reaction conditions. The tests were performed using n -hexadecane as a model feedstock. The screening of pressure and temperature conditions indicates that the best match for both catalysts is 20 atm and 225 °C. Stable activity levels for both catalysts can only be achieved at a H 2 / n -C 16 ratio of 10. An adequate space velocity for increasing the yield to iC 5–9 and preventing consecutive cracking is 18.4 h − 1 . At this process conditions mixtures (PtWZ + PtSZ) that contain 25% or 50% PtSZ have a better product distribution, with the maximum displaced to higher carbon numbers, with a reduced yield to isobutane and light gasses. Operation points lie on a monotonic curve of octane number gain (∆RON) as a function of the yield of light gasses (C 1–4 ) that indicates that RON gains can only be obtained at the expense of the liquid yield.

A study of the different hydrocarbon reactions over Ni doped WO3-ZrO2 catalysts was performed. Ni was found as NiO at low Ni concentration while at high Ni concentrations a small fraction was present as a metal. For both cases, Ni strongly modified total acidity and concentration of strong acid sites. In the cyclohexane dehydrogenation reaction, Ni addition promotes both benzene and methyl cyclopentane production. The hydroconversion activity (n-butane and n-octane) increases with the augment of total acidity produced by Ni. The selectivity to reaction products is modified according to the acid strength distribution changes produced by Ni addition. Fil: Torres, Gerardo Carlos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; Argentina Fil: Manuale, Débora Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; Argentina Fil: Benitez, Viviana Monica. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; Argentina Fil: Vera, Carlos Roman. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; Argentina Fil: Yori, Juan Carlos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; Argentina

An assessment of the process conditions for the isomerization-cracking of long-chain n-paraffins over commercial Pt/SO42--ZrO 2 catalysts was made. Pretreatment and reaction conditions were optimized with a focus on the maximization of the yield of short, high octane branched paraffins for the gasoline pool. While selectivity was an important issue attention was also paid to the reduction of the yield to gases (C 1-C4). Therefore cracking had to be modulated to produce the correct molecular size adjustment without scission to too much smaller fragments. Skeletal isomerization was to be maximized. The activity in both acid-catalyzed reactions had to be tuned while keeping a stable activity level. The only pretreatment condition assessed was the calcination temperature (screened in the 600-800 °C range). Calcination at 600 °C produced the highest activity level while 700 °C was convenient from the point of view of selectivity. The optimum temperature coincided with the production of the highest concentration of Brönsted acid sites. Regarding the reaction conditions, increasing temperature values augmented the conversion but also increased the cracking. Therefore optimum values were found at a moderate temperature, 225 °C, given the high reactivity of the feed. Space velocity values were analyzed with attention to the liquid C5+ yield, the selectivity to branched isomers and the stability of the catalysts. Best yields to branched naphtha products were obtained at WHSV = 18 h- 1. The H2/hydrocarbon molar ratio was a function of the catalyst coking rate. A value of 10 was enough to attain a stable conversion value. The values of liquid yield as a function of pressure displayed a volcano pattern that was rationalized in terms of a non-classical bifunctional mechanism of reaction. High pressure values increased the concentration of Brönsted acid sites and hence the activity while high pressures enhanced hydrocracking and decreased the liquid yield. The optimal pressure value was 20 atm. Fil: Busto, Mariana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentina Fil: Vera, Carlos Roman. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentina Fil: Grau, Javier Mario. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentina

Background: Arsenic decontamination of drinking water by adsorption is a simple and robust operation. When designing packed bed adsorbers for arsenic, the main problems are the slow diffusion kinetics of As in microporous media and the lack of simple equations for predicting the performance of the equipment. Commercial iron-doped granular activated carbon adsorbents (Fe/GAC) for groundwater arsenic abatement were studied in this work. Basic parameters for arsenate (AsV) adsorption were measured and their performance at larger scale was simulated with an approximate analytical model. Results: In the 0-300 μgAs L-1 range, the AsV adsorption isotherm on Fe/GAC was found to be approximately linear. Assuming Henry's law for adsorption and homogeneous surface diffusion with constant diffusivity for intrapellet mass transfer, an approximate model for flow and adsorption of arsenate inside packed bed adsorbers was developed, and reduced to an analytic compact solution using the quasi-lognormal distribution (Q-LND) approximation. The use of this model with fitted and reported parameters enabled the approximate simulation of industrial adsorbers and home point-of-use filters. Results show that industrial adsorbers meet the breakthrough condition with incomplete utilization of the adsorbent unless convenient process configurations are used. In point-of-use systems with short residence times intraparticle diffusion would drastically reduce the adsorbent performance. Conclusion: Assuming linear adsorption of AsV over Fe/GAC, an analytical approximate solution for flow and adsorption in packed beds can be obtained. The model seems to represent correctly the main features of industrial and home filters, however, more experimental data is necessary for scale-up purposes. Fil: Sigrist, Mirna Edit. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Programa de Investigación y Análisis de Residuos y Contaminantes Químicos; Argentina Fil: Beldomenico, Horacio Ramon. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Programa de Investigación y Análisis de Residuos y Contaminantes Químicos; Argentina Fil: Tarifa, Enrique Eduardo. Universidad Nacional de Jujuy. Facultad de Ingeniería; Argentina Fil: Pieck, Carlos Luis. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentina Fil: Vera, Carlos Roman. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentina

Different feedstocks of varying acidity ranks and water contents were subjected to a series of discontinuous steps that simulated a biodiesel production process. The three steps comprised: (i) the non-catalytic transesterification with supercritical methanol at 280 °C; (ii) the distillation of the unreacted methanol, water and volatile products; and (iii) the adsorption of the impurities with adequate adsorbents. Refined soy oil, chicken oil and waste cooking oil were subjected to the same simple procedure. The process produced biodiesel complying with the water, acid, glycerides and methyl esters content specifications of the EN 14214 standard. Biodiesel production by the reaction of oils in supercritical methanol at 280 °C and methanol-to-oil molar ratios of 15 and 20 produced amounts of glycerol as small as 0.02%. This simplified the subsequent refining of the biodiesel and is considered an advantage over the classic alkali-catalyzed process (that produces 10% of glycerol by-product) because washing steps can be spared. The contents of methyl esters, water and free fatty acids showed a volcano pattern when plotted as a function of the reaction time. In the case of the free fatty acids this was attributed to the initial reaction of water and triglycerides to form acids and glycerol that increased the acidity of the product mixture. At longer reaction times these acids were likely transformed into methyl esters or were decarboxylated to hydrocarbons and CO 2 . Water formation was attributed to glycerol decomposition and esterification of free fatty acids. The design of a simple process for biodiesel production using a single reaction step with negligible glycerol production and an adsorption-based refining step was thus studied. A possible scheme integrating reaction, methanol recycling, biodiesel purification and heat recovery was discussed. Advantages and disadvantages of process units were analyzed on terms of operating cost and simplicity.

It has been demonstrated that using low-cost materials and a relatively simple process, complex supports with a mixed inorganic–organic structure can be synthesized. These supports combine hydrophilic–hydrophobic dual properties and are especially suited for preparing egg-shell supported metal catalysts to be used in highly exothermal catalytic reactions or in systems of consecutive reactions where diffusive problems decrease the selectivity. The synthesized supports have an extremely thin active layer. They also proved to be more mechanically resistant than other commercial supports thus being amenable for use in continuous processes with long packed beds. Pd catalysts supported over the new composite materials were found to be highly active for the selective hydrogenation of styrene, a representative compound of pyrolisis gasolines. They also displayed smaller diffusive constraints than other Pd catalysts prepared from commercial supports.

The poisoning resistance to sulfided and oxygenated compounds of some VIII Group PYGAS selective hydrogenation catalysts based on metals was assessed. Low content alumina supported Rh, Pd, Ru and Pt catalysts (0.35 wt%) were prepared from chlorided precursors. In the case of the palladium catalysts a nitrogenated precursor was also used. The catalysts were mainly assessed in the catalytic test of selective styrene hydrogenation in the presence or absence of known poisons. Model feedstocks spiked with thiophene, thiophane and tetrahydrofuran were used. The catalysts were further characterized by means of chemical analysis, XPS, TPR and chemisorption. The results indicate that chlorided precursors yield more sulfur resistant catalysts. The effect was attributed in part to the formation of oxychlorinated species, refractory to reduction, that leave the metal in an electron deficient state, thus inhibiting the formation of strong poison-metal bonds, the chloride species could also be a steric factor that can contribute to the sulfur resistance of the catalyst. Pd based catalyts had the highest activity and resistance to poisons of all the metals tested. This superior performance was attributed in part to the total occupancy of the 4d electronic levels of the Pd metal that was supposed to promote the rupture of the H2 bond during the hydrogenation reaction. Fil: Badano, Juan Manuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentina Fil: Quiroga, Monica Esther. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentina Fil: Betti, Carolina Paola. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentina Fil: Vera, Carlos Roman. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentina Fil: Canavese, Sergio Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentina Fil: Coloma Pascual, F.. Universidad de Alicante; España

Ru-Sn/Al2O3 catalysts with different Sn loadings were prepared by the coimpregnation method. Several characterization techniques such as TPR, pyridine TPD and catalytic tests for dehydrogenation and hydrogenolysis were used to evaluate and compare such catalysts. TPR results indicate that Sn is deposited both onto the support and as species strongly interacting with Ru. Such non selective deposition modifies the acid and metallic functions of the catalysts. Both total acidity and acid strength distribution are affected: total acidity decreases and new sites of lower acid strength are created. Both dehydrogenating and hydrogenolytic activities are strongly diminished by the addition of Sn. Results of catalytic tests for methyl oleate hydrogenation indicate that methyl stearate is the main product, with only minute amounts of oleyl alcohol produced, and that the addition of Sn diminishes the hydrogenation activity.

New acidic materials with fairly uniform mesoporous texture were synthesized by deposition of tungsten promoted (WZ) over a wide pore silica carrier (SiO2). High dispersion of the tungsten-zirconia crystallites was achieved by a two-step controlled impregnation procedure. A first deposition of zirconia was performed by controlled hydrolysis of alkoxide. Impregnation of tungstate was performed by incipient wetness impregnation of ammonium metatungstate. The catalysts show an activation pattern for the reaction of 1-butene similar to bulk tungsten-zirconia catalyst with an optimum at a calcination temperature of 750 °C. Supported zirconia crystallizes almost exclusively as tetragonal crystallites. The catalysts were tested in the reaction of hydroisomerization cracking of octane (300 °C, 1 atm, WHSV=1 h−1 and H2/nC8= 6 mol/mol) for the production of light isoalkanes (isobutane, isopentane, isohexane) of high octane number. The tried catalysts had a high catalytic activity and this result was related to the high surface area. Both bulk and deactivated rapidly if they did not contain Pt. Impregnation with Pt and the use of H2 in the reaction medium enable the hydrogenation of coke precursors and the stabilization of the catalyst. A stable performance was obtained at a moderate activity level. This was attributed to the presence of Pt/SiO2 particles with a stronger metal function than Pt/WZ due to a lower metal support interaction. The supported catalysts would have a higher hydrogenating activity and this would be crucial for enhancing their stability in comparison to bulk Pt/WZ. Tungsten addition to zirconia in amounts greater than 7.5% produced segregation of a WO3 phase in the form of crystallites that plugged pores and produced a reduction of the available area and hence of the overall catalytic activity. For the WZ supported catalysts activity as a function of calcination temperature had a pattern similar to that of bulk WZ catalysts. Supported WZ catalysts were more stable in the n-octane isomerization reaction and reached a pseudo steady state even at very low H2 partial pressures while bulk WZ catalysts deactivated continuously and stabilized only at high H2 partial pressures. On a mass basis of active WZ phase some supported catalysts had a higher activity than bulk WZ. They also have a more open pore structure more suitable for the reaction of bulky molecules. However the dilution effect of silica produces catalysts with a relatively low activity per unit volume. Fil: Busto, Mariana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentina Fil: Lovato, Maria Eugenia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnológico para la Industria Química; Argentina Fil: Vera, Carlos Roman. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentina Fil: Shimizu, Kiyoyuki. Council for Science and Technology Policy; Japón Fil: Grau, Javier Mario. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentina

Alumina supported bimetallic Pt-Re, Pt-Sn and Pt-Ge naphtha reforming catalysts were studied. The Pt concentration was kept constant at 0.3% (weight basis) while the concentration of the second metal was varied in order to assess its influence. The experimental results showed that the addition of a second metal (Re, Sn, Ge) to the Pt catalyst produces a modification of the metal and acid functions. Sn and Ge produce similar modifications of the metal function: a marked decrease of the dehydrogenation and hydrogenolytic capacity of Pt. The addition of Re modifies the dehydrogenation capacity to a lower extent than the addition of Sn or Ge. The hydrogenolytic capacity is increased upon Re addition. The changes on the acid function are different depending on which metal is added. Re and Ge modify the acid strength distribution; they favor the formation of sites of lower acid strength but they keep the total concentration of acid sites almost constant. Conversely Sn addition not only produces a change in the acid strength distribution but also a decrease of the total acidity of the catalyst. Fil: Mazzieri, Vanina Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentina Fil: Grau, Javier Mario. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentina Fil: Yori, Juan Carlos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentina Fil: Vera, Carlos Roman. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentina Fil: Pieck, Carlos Luis. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentina

The objective of this work was to assess some of the points that need to be elucidated in order to define the economic viability of the noncatalytic supercritical biodiesel process. Net yield of the supercritical process, consumption of methanol, and the quality of the fuel issuing from the reactor were studied. Biodiesel was prepared by reacting refined soy oil with supercritical methanol at T ) 280 C and methanol-to-oil molar ratios of 15 and 20. After the reaction, unreacted methanol, water, and other volatile compounds were removed from the product by stripping with nitrogen at 110 C. Biodiesel production by the reaction of oils in supercritical methanol under the conditions used in this work produces practically no glycerol byproduct. This fact simplifies the downstream refining of the produced biodiesel. Glycerol is transformed into products of smaller molecular size and water. At first this water reacts with the triglycerides of the reacting mixture to form free fatty acids (FFA), thus increasing the acidity of the product. At longer reaction times the acids are converted into methyl esters again. Glycerol methanolysis reactions increase the methanol consumption. The small amount of glycerides and FFA contaminants in the biodiesel product makes a final step of refining by silica adsorption convenient. No liquid effluents are issued with such a refining step. After the FFA and glycerides are recycled, the yield of the process is 94-96. Fil: Aimaretti, Nora Rosa. Universidad del Centro Educativo Latinoamericano; Argentina Fil: Manuale, Débora Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; Argentina Fil: Mazzieri, Vanina Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; Argentina Fil: Vera, Carlos Roman. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; Argentina Fil: Yori, Juan Carlos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; Argentina

The effect of the Ge content on the properties of the metal and acid functions of trimetallic naphtha reforming catalysts of platinum-rhenium-germanium supported on chloride alumina was studied. Pt, Re and Ge were loaded using the coimpregnation method. The elemental concentration of the catalysts used was: Pt = Re = 0.3%; Ge = 0.1%, 0.3%, 0.6% and 0.9% (weight basis). In order to make a comparison Pt/Al2O3 and Pt-Re/Al2O3 catalysts were prepared. The properties of the acid and metal functions were studied by physicochemical techniques and using test reactions. Reforming of n-heptane (450 °C, 0.1 MPa, H2/nC7 = 4, WHSV = 7.3) was used to evaluate the catalytic properties of the samples. It was found that the addition of small quantities of Ge (0.1%) decreased both the hydrogenolytic and dehydrogenation activities by breaking Pt-Re ensembles and modifying the electronic density of Pt. The latter was revealed by the decrease in the CO chemisorption capacity and the shift of the bands of linearly adsorbed CO. With respect to the acid function Ge addition produced a change in the acid strength distribution, increasing the amount of mild and weak acid sites and decreasing the amount of strong ones. This modification of the metal/acid balance had an effect over the distribution of products of n-heptane reforming. Both the isomerization activity and the stability of the catalyst were enhanced while the cracking and dehydrocyclization activities were decreased. The isoparaffins/aromatics ratio and the octane gain were improved and as a result the reformate product better adjusted to environmental regulations. Fil: Mazzieri, Vanina Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentina Fil: Pieck, Carlos Luis. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentina Fil: Vera, Carlos Roman. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentina Fil: Yori, Juan Carlos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentina Fil: Grau, Javier Mario. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentina

The properties of a commercial Pt/WO3-ZrO2 for the simultaneous hydro-isomerization of n-hexane and benzene have been assessed at varying values of total system pressure, fixed reaction temperature (300 °C), and molar ratio H2/HC ) 6. A total pressure of 20 atm was satisfactory for performing both the hydrogenation of benzene and the isomerization of C6 at convenient reaction rates. Greater pressures increased the cracking and formation of light gases. Also, the total conversion was decreased at higher pressures. Benzene conversion proceeded by metal-catalyzed hydrogenation and subsequent acid-catalyzed ring contraction with no occurrence of ring opening. The results show that the presence of a small amount of benzene (3%, vol/vol) is beneficialfor the hydro-isomerization of n-hexane over Pt/WO3-ZrO2. Hydrocracking is largely suppressed, and both the liquid C5+ yield and the selectivity to branched isoparaffins are enhanced. Sulfur impurities in the feed decrease the n-hexane and benzene conversion by poisoning the metallic function, and their concentration should be lowered to less than 10 ppm to avoid producing an important inhibiting effect. Fil: Busto, Mariana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentina Fil: Grau, Javier Mario. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentina Fil: Canavese, Sergio Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentina Fil: Vera, Carlos Roman. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentina

The refining of biodiesel by adsorption over silica gel was assessed. Silica gel samples were used for the adsorption of glycerol and monoglycerides. Room-temperature isotherms for the adsorption of glycerol were measured for biodiesel samples contaning only fatty acid methyl esters or samples spiked with contaminants, such as water, methanol, monoglycerides, and soaps. The results indicate that adsorption of glycerol and monoglycerides contained in biodiesel over silica is very efficient and robust. Adsorption of glycerol is not influenced by the presence of small amounts of water arid soaps. The presence of monoglycerides lowers the adsorption capacity of glycerol because of the competition of monoglycerides for the same adsorption sites. Methanol adversely affects the adsorption in a different way. It increases the activity of glycerol in the liquid phase and reduces the adsorption affinity and adsorption capacity of silica. Conventional biodiesel refining downstream transesterification reactors currently performed by decanting/washing or centrifugation/washing can be conveniently replaced by simple decanting and silica adsorption, thus preventing the issue of excessive amount of effluent waters. Fil: Mazzieri, Vanina Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentina Fil: Vera, Carlos Roman. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentina Fil: Yori, Juan Carlos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentina

The objective of this work was to optimize the acid function and metallic function of a Pt-Pd/WO3-ZrO2 catalyst for isomerization-cracking of long paraffins. The calcination temperature and the W content were the preparation variables varied and studied. The catalysts were tested in the reaction of n-decane isomerization-cracking. The focus of the optimization was put on the synthesis of a catalyst with a good isomerizing activity and a minimum activity for the formation of light gases. In this way an isomerizate of high octane number and high liquid yield would be obtained and used for blending into the gasoline pool. The catalysts were further characterized by temperature programmed desorption of probe molecules (TPD). Varying both the W content and the calcination temperature enabled the regulation of the acid function properties. Thus both the activity and selectivity could be fine-tuned. The highest activity was obtained with the samples with a 15% of W and calcined at 700 °C. The samples calcined at 700 °C were also the most stable ones, i.e. the activity of the acid function was less affected by coking. All the prepared catalysts produced a high octane number gain that was between 75 and 95 points and low yields of light gases (

Liquid phase cyclohexanol catalytic oxidation to cyclohexanone and epsilon(ε)-caprolactone were studied using aqueous hydrogen peroxide as oxidant and H3PW12O40 (HPA) and H0.5Cs2.5PW12O40 (Cs-salt) as catalysts. The hydrophobic and insoluble Cs-salt showed the highest activity (per unit catalytic weight and turnover number) and selectivity to (ε)-caprolactone. The ultrafine Cs-salt crystallites could be filtrated and recycled. Solvent effects on the activity and selectivity and the rate of peroxide decomposition were assessed and they were correlated to their polarity and protic/aprotic nature. When employing acetonitrile at 90 °C the highest activity and selectivity were achieved and also the lowest rate of hydrogen peroxide decomposition. Fil: Balbinot, L.. Universidade Estadual de Campinas; Brasil Fil: Schuchardt, U.. Universidade Estadual de Campinas; Brasil Fil: Vera, Carlos Roman. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentina Fil: Sepúlveda, Juan. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentina

The effect of the temperature of calcination of the support on the structural properties of ZrO 2 and on the activity of the acid and metal functions of a Pt/WO x -ZrO 2 catalyst used in the isomerization—cracking of medium length paraffinic C 8 -C 12 cuts was studied. n-Octane was used as model molecule. The calcination temperature was varied in order to change the metal/acid balance and to increase the yield of the reaction to isoparaffins of high octane number. Four supports were prepared by impregnating Zr(OH) 4 with ammonium metatungstate (15% W) and then they were calcined at 500, 600, 700, and 800 °C. These supports were then impregnated with H 2 Cl 6 Pt (1% Pt) and calcined in air at 500 °C. They were characterized by means of chemical analysis, XRD, N 2 adsorption, pyridine TPD, hydrogen chemisorption, temperature-programmed reduction, and infrared spectroscopy of adsorbed CO. The catalytic activity of the catalysts was evaluated with the test reactions of n-octane (300 °C, 1 atm, WHSV =1, H 2 /n-C 8 = 6), n-butane (350 °C, WHSV = 1, H 2 /n-C 4 = 6), and cyclohexane (300 °C, 1 atm, WHSV = 12.6, H 2 /CH = 1.4). The results reveal a strong influence of the calcination temperature on the final metal/acid balance of the catalysts. At 5 min time on stream, all catalysts produce a RON gain of 55 points. In general, the higher the calcination temperature the higher the promoting action of W for generating strong acid sites and the higher the concentration of Pt δ+ of the metal function. The highest liquid yield and isoparaffin yield were obtained with the sample calcined at 700 °C. The sample calcined at 800 °C had the highest cracking activity and the maximum yield of isobutane and propane.

The effect of the addition of Pd on the catalytic activity and selectivity of Pt/WZ for isomerization-cracking of linear heavy paraffins was assessed using n-octane as model feedstock. A focus was put on obtaining an optimized catalyst with good isomerization activity and minimum cracking in order to get a product with improved RON and a minimum production of light gases. The results were compared with those obtained with a Pt/SO42−–ZrO2 (Pt/SZ) catalyst used as reference. The catalysts were further characterized by means of N2 adsorption, X-ray diffraction, temperature programmed desorption of probe molecules and cyclohexane dehydrogenation. The n-C8 results indicate that the simultaneous addition of Pt and Pd to a WZ catalyst produces a decrease of the total acidity and an increase of the de/hydrogenating capacity as compared to the monometallic Pt/WZ and Pd/WZ catalysts. This effects allows the tuning of the metal and acid functions of the catalysts, optimizing the balance for the mild isomerization-cracking reaction. In this sense, high values of RON gain were measured in the product and a high C5+ liquid yield was obtained.

The deactivation, by coke deposition and sintering, and the regeneration of the metal function of PtReSn/Al 2 O 3 –Cl and PtReGe/Al 2 O 3 –Cl catalysts were studied. The variables affecting the rejuvenation of the metal function (oxychlorination at 480 °C with 300, 530 and 900 ppm, stabilization at 520 °C) and the coke burning-off (400–500 °C, 0.5, 2, 6 or 12 h) were assessed. The analysis of the carbon deposits and of the final state of the metal and acid functions were performed by means of temperature programmed oxidation, temperature programmed reduction and temperature programmed pyridine desorption (TPO, TPR and TPD-Py) respectively. The degrees of deactivation and activity recovery of the metal function were measured by means of the cyclohexane dehydrogenation and cyclopentane hydrogenolysis reactions. The deactivation or activity recovery of the acid function assessed with the n -pentane isomerization reaction. It was found that the PtReSn catalysts were more stable than the PtReGe ones. This was due to the lower amount of coke deposited on the surface of PtReSn. It was found that when the catalysts were oxidized with an oxygen stream more than 6 h were needed to eliminate the coke at 400 °C while at 500 °C the coke was eliminated in 30 min. Regeneration produced a segregation of the metal phase on both kinds of catalysts. Metal particle sintering at 650 °C modified the metal function severely and Pt was segregated from the other components. All the rejuvenation treatments (Cl, air and high temperature) were unable to restore the original state of the metal function.

Pt-Re-Ge/γAl2O3 catalysts were prepared by the catalytic reduction method using different impregnation media (H2O, HCl and NH3) and different Ge contents (0.0, 0.1, 0.3, 1.0 and 2.0%). The influence of these preparation parameters on the activity for n-heptane conversion and the selectivity to toluene at atmospheric pressure was assessed. The catalysts were also characterized by ICP-AES, temperature programmed reduction, pyridine temperature programmed desorption and CO pulse chemisorption. The results show that as the pH is increased the Ge content increases and the catalysts present a lower hydrogenolytic activity and a lower toluene selectivity. Ge addition modifies both metal and acid functions. The catalyst with minimum Ge content prepared using water as impregnation medium has the best performance.

Low-cost tungsten monometallic catalysts containing variable amounts of metal (4.5, 7.1 and 8.5%W) were prepared by impregnating alumina with ammonium metatungstate as an inexpensive precursor. The catalysts were characterized using ICP, XPS, XRD, TPR and hydrogen chemisorption. These techniques revealed mainly WO3-Al2O3 (W6+) species on the surface. The effects of the content of W nanoparticles and reaction temperature on activity and selectivity for the partial hydrogenation of 3-hexyne, a non-terminal alkyne, were assessed under moderate conditions of temperature and pressure. The monometallic catalysts prepared were found to be active and stereoselective for the production of (Z )-3-hexene, had the following order: 7.1WN/A > 8.5 WN/A ≥ 4.5 WN/A. Additionally, the performance of the synthesized xWN/A catalysts exhibited high sensitivity to temperature variation. In all cases, the maximum 3-hexyne total conversion and selectivity was achieved at 323 K. The performance of the catalysts was considered to be a consequence of two phenomena: a) the electronic effects, related to the high charge of W (+6), causing an intensive dipole moment in the hydrogen molecule (van der Waals forces) and leading to heterolytic bond rupture; the H+ and H- species generated approach a 3-hexyne adsorbate molecule and cause heterolytic rupture of the C≡C bond into C- = C+; and b) steric effects related to the high concentration of WO3 on 8.5WN/A that block the Al2O3 support. Catalyst deactivation was detected, starting at about 50 min of reaction time. Electrodeficient W6+ species are responsible for the formation of green oil at the surface level, blocking pores and active sites of the catalyst, particularly at low reaction temperatures (293 and 303 K). The resulting best catalyst, 7.1WN/A, has low fabrication cost and high selectivity for (Z )-3-hexene (94%) at 323 K. This selectivity is comparable to that of the classical and more expensive industrial Lindlar catalyst (5 wt% Pd). The alumina supported tungsten catalysts are low-cost potential replacements for the Lindlar industrial catalyst. These catalysts could also be used for preparing bimetallic W-Pd catalysts for selective hydrogenation of terminal and non-terminal alkynes. Fil: Maccarrone, María Juliana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; Argentina Fil: Lederhos, Cecilia Rosa. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; Argentina Fil: Betti, Carolina Paola. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; Argentina Fil: Carrara, Nicolás Ricardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; Argentina Fil: Yori, Juan Carlos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; Argentina Fil: Coloma Pascual, Fernando. Universidad de Alicante. Facultad de Ciencias; España Fil: Liprandi, Domingo Antonio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; Argentina Fil: Vera, Carlos Roman. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; Argentina Fil: Quiroga, Monica Esther. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; Argentina

The effect of WO 3 loading on the acidity and specific surface area of catalysts composed of Pt supported on ZrO 2 and double-promoted with SO 4 2- and WO 3 catalysts (PtWSZ) was studied. The catalysts were tested in the isomerization cracking of heavy alkanes, and the objective was to assess their ability to produce branched shorter alkanes, contributing to the gasoline pool. As a consequence, the focus was put on the maximization of the yield of C 4 -C 7 isomers (i-C 4-7 ). The catalysts were characterized by several techniques. The crystalline structure was analyzed by XRD. The acidity of the catalysts was measured by thermal desorption of pyridine. A screening and first selection of the most promising catalysts was done by means of the reaction of n-octane at 300 °C, 0.1 MPa, WHSV = 1 and H 2 /nC 8 = 6 mol/mol. A high yield of i-C 8 was obtained with the Pt/ WO 3¯ ZrO 2 catalyst. The incorporation of SO 4 2- as a promoter increased the acidity and the cracking activity. Pt/SO 4 2- ¯ ZrO 2 displayed very strong acid sites and generated the highest amount of light hydrocarbons. Catalysts of regulated acidity combining both promoters yielded the best results. The most promising PtWSZ catalyst was obtained with 5% W and 1.4% S. The test reaction of n-decane at near-industrial conditions (1.5 MPa, 300 °C, WHSV = 4, H 2 /n-C 10 = 6 mol/mol) was used for a further assessment of the catalytic properties. This test confirmed that the double-promoted catalyst (PtWSZ, 5% W, 1.4% S) had high activity and stability and produced an isomerizate with the highest i-C 4-7 /i-C total molar ratio in comparison to the sulfated zirconia (PtSZ) and tungstated zirconia (PtWZ) catalysts.

This is a study on the kinetics of the liquid-phase hydrogenation of styrene to ethylbenzene over a catalyst of palladium supported on an inorganic–organic composite. This support has a better mechanical resistance than other commercial supports, e.g. alumina, and yields catalysts with egg-shell structure and a very thin active Pd layer. Catalytic tests were carried out in a batch reactor by varying temperature, total pressure and styrene initial concentration between 353–393 K, 10–30 bar, and 0.26–0.60 mol L−1. Kinetic models were developed on the assumptions of dissociative hydrogen chemisorption and non-negligible adsorption of hydrogen and styrene. Final chemical reaction expressions useful for reactor design were obtained. The models that best fitted the experimental data were those ones that considered the surface reaction as the limiting step. In this sense, a two-step Horiuti–Polanyi working mechanism with half hydrogenation intermediates gave the best fit of the experimental data. The heats of adsorption of styrene and ethylbenzene were also estimated. Fil: Betti, Carolina Paola. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; Argentina Fil: Badano, Juan Manuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; Argentina Fil: Lederhos, Cecilia Rosa. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; Argentina Fil: Maccarrone, María Juliana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; Argentina Fil: Carrara, Nicolás Ricardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; Argentina Fil: Coloma Pascual, Fernando. Universidad de Alicante; España Fil: Quiroga, Monica Esther. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; Argentina Fil: Vera, Carlos Roman. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; Argentina