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Liquid phase hydrogenation of acetophenone (ACT) is studied over ruthenium catalysts (1-4 wt% Ru) supported on gel-type methacrylate-styrene resin (FCN) functionalized with C=O, –NH, and –NH2 groups. Microscopic studies (SEM, STEM) show that the nature of Ru particles depends on the level of Ru doping. At low Ru content (1–2 wt%) ruthenium nano-clusters are formed, while at 4 wt% Ru, metal crystallites of few nanometers in size are observed. Catalytic reactions are performed at mild conditions (atmospheric pressure of hydrogen, 40 °C) in biphasic isooctane-water (IO/H2O) solvent system, and, for comparison, in a single component solvent (isooctane or ethanol). The use of biphasic IO/H2O solvent system results in a dramatic improvement of selectivity. The hydrogenation of C=O in acetophenone dominates over the hydrogenation of aromatic ring, yielding 1-phenylethanol with ca. 80% selectivity. Ru/FCN catalysts exhibit higher selectivity than the reference Ru/Al2O3. This is tentatively assigned to the steric effects induced by the polymer network on migrating reactant molecules. Advantageous influence of biphasic IO/H2O solvent system has been attributed to the solvation of phenyl ring of acetophenone by non-polar isooctane, which facilitates the interaction with the catalyst surface via carbonyl group and leads to the preferential reduction to 1-phnenylethanol. Liquid phase hydrogenation of acetophenone was studied over ruthenium catalysts (1–4 wt% Ru) supported on diamine group functionalized gel-type polymer (FCN).

Present research concentrates on the process of anthraquinone degradation in the course of hydrogenation carried out in the presence of palladium catalyst. Hydrogenation experiments were carried out using agitated glass laboratory batch type reactor at atmospheric pressure of hydrogen and temperature of 55 °C. Catalytic tests were performed using solutions composed of 2-ethyl-9,10-anthraquinone (eAQ) and a mixture of eAQ and 2-ethyloxanthrone (OXO) with various proportions. Degradation of anthraquinone was studied and in particular, the role of reduced forms of quinone namely hydroquinone and its tautomer OXO is discussed. A difference in the course of reactions pathways: hydrogenation of aromatic rings to give 2-ethyl-5,6,7,8-tetrahydro-9,10-anthraquinone (active quinone) and hydrogenolysis reactions yielding degradation products was observed. Present research concentrates on the process of 2-ethyl-9,10-anthraquinone degradation on palladium catalyst. The role of reduced forms, hydroquinone-enol form and its keto-tautomer is discussed.

The cesium salts Cs x H3−x PW12O40 of Cs content x = 2 up to x = 3 were tested as the catalysts in the gas and liquid phase reactions. Dehydration of ethanol and transesterification of triglycerides with methanol were selected as the catalytic reactions. Apart from the standard preparation, the catalysts were prepared by two-stage procedure with methanol or water as a solvent. The Cs-salts were characterized by FT-IR, XRD, scanning electron microscopy and energy dispersive X-ray techniques. In turn, the influence of Cs-salts composition on the pH and conductivity of their aqueous colloidal solutions was investigated. The results obtained by the latter techniques were also characteristic for acidity of surface layer of colloidal particles because of surface layer-solution equilibrium. It has been shown that the secondary structure of acidic cesium salts existing in crystalline samples (solid solution of H3PW12O40 in Cs3PW12O40) changes after contacting with polar medium to the system consisting most probably of Cs3PW12O40 core with epitaxial layer of heteropolyacid. This is result of the protons migration from bulk to surface layer of primary particles enhanced by polar medium. It strongly influences the surface acidity of primary particles as well as the activity of Cs-salts in transesterification of triglycerides with methanol. In such polar medium, Cs2HPW12O40 salt becomes the most active catalyst, more active than Cs2.5H0.5PW12O40. An accumulation of partial glycerides and in particular glycerol on the surface of primary particles of Cs-salts resulted in relatively low maximum conversion of triglycerides, most probably due to partial blockage of the catalytic centers. This effect and the almost constant activity of Cs-salts under recycling use in the transesterification experiments are considered to be experimental evidences that methanolysis over Cs-salts was accomplished with the participation of surface protons.

Methanolysis of castor oil to methyl esters, a key step in Biodiesel production, was studied with the use of KOH, H2SO4 and 12-tungstophosphoric acid (H3PW12O40, HPW) as the homogeneous catalysts. Reaction was also performed in the presence of solid salts of HPW, namely M x H3−x PW12O40, where M = K or Cs and x = 2, 2.5 and 3 (abbreviated as K2, K2.5, K3 and Cs2, Cs2.5, Cs3, respectively). The HPW salts were precipitated by K2CO3 and Cs2CO3 or CsCl. Their properties were characterized by BET, electron microscopy (SEM, EDS) and colloidal particles size distribution (laser diffraction technique). The potassium doped HPW samples, K2 and K2.5, prove to be much more active catalysts (ca. 3 times) than their Cs-containing analogues. Among the K, Cs salts, K2 salt was the most active catalyst. The activity of catalysts was found to depend on preparation stages such as the temperature of drying or annealing and aging of the samples. Microscopic studies evidenced colloidal form of Cs and K salts particles under the catalytic reaction. The size of colloidal particles was found to depend upon the type of cation, Cs+ or K+, as well as the “history” of catalysts preparation (temperature of drying). Based on the results obtained in this work, we concluded that activity was determined by the accessibility of the reactants to acid sites which is facilitated by the high surface area and open structure of the colloidal form. This may lead to better utilization of acid sites and higher activity of samples with lower content of K+ or Cs+ cations in the HPW.

Functional gel type resins of various crosslinking degrees (3–20%) with C=O and carboxylic groups were used as the supports for Pd catalysts (0.5–2 wt% Pd). The role of polymer properties was studied in the hydrogenation of 2-Butyne-1,4-diol (B3-D) to alkene (B2-D) and alkane (B1-D). Hydrogenation was studied at atmospheric pressure of hydrogen using THF, H2O and THF + H2O mixtures as the solvents. Systematic studies were carried out to determine the role of the type of solvent, crosslinking degree of polymer, the content of Pd in catalysts, initial B3-D concentration and the procedure of catalyst reduction in activity/selectivity behaviour of catalysts. Swelling degree of polymer matrix under the catalytic run exhibits crucial role in the activity and selectivity to alkene, B2-D. In the presence of highly expanded catalyst (THF solvent, 3% crosslinking degree, 1 wt% Pd) the alkyne, B3-D, is hydrogenated to alkene, B2-D, with selectivity ca. 85% up to high B3-D conversion (90%). The suppression of alkene to alkane hydrogenation in the stage of B3-D is ascribed to high ability of Pd centres in the Pd/OFP catalysts to strong adsorption of alkyne substrate. It may also be related to steric hindrances of polymer in the vicinity of active Pd centres. At small content of added water (5% by vol.) to THF the catalysts offer very attractive performance in terms of activity and 98% selectivity to alkene. Water facilitates interactions of B3-D with functional groups of polymer that leads to better expansion of polymer matrix and more effective suppression of alkene hydrogenation in the alkyne stage.

By doping of polyaniline (PANI) in PdCl2 aqueous and ethanol solutions the catalysts containing crystalline and colloidal Pd particles of different sizes were prepared. The size of palladium particles present in Pd/PANI catalysts (characterised by SEM and XRD methods) influenced the course of 2‐ethylanthraquinone (eAQ) hydrogenation, a key step in the industrial production of H2O2. The presence of large palladium particles promotes reactions leading to the formation of the so‐termed “degradation products” not capable of hydrogen peroxide formation.