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The loading strategy of cocatalysts affects its activity exerting and atom utilization. Here, a novel strategy for loading precious metal (Pt) cocatalysts by means of ultrathin N-doped carbon layer is reported. The strategy is based on a pyrolysis process of predesigned N-containing polymers and Pt complexes on hard-template surface, during which Pt can be reduced by carbon from pyrolysis at high temperatures. Finally, the hollow TiO2 composite with stable and dispersed Pt on its inner surface was prepared. It shows an ultrahigh photocatalytic H2 production activity as high as 25.7 mmol h−1 g−1 with methanol as sacrificial regent, and displays an apparent quantum yield as 13.2%. The improved photocatalytic activity and stability can be attributed to the highly dispersed and ultrafine Pt nanoparticles, enhanced interaction between Pt-species and carbon support, fast photo-excited electron transport from the high graphitization degree of NC layers, ample oxygen vacancies/defects, as well as the manipulated local charge distribution of Pt/NC-layer configuration. Additionally, the universality of the proposed strategy was demonstrated by replacing metal sources (such as, Ru and Pd). This work presented a promising strategy for the design and development of novel photocatalysts, which shows a broad application prospect.

Sluggish kinetics of methanol oxidation reaction (MOR) and alkaline hydrogen evolution reaction (HER) even on precious Pt catalyst impede the large-scale commercialization of direct methanol fuel cell (DMFC) and water electrolysis technologies. Since both of MOR and alkaline HER are related to water dissociation reaction (WDR), it is reasonable to invite secondary active sites toward WDR to pair with Pt for boosted MOR and alkaline HER activity on Pt. Mo2C and Ni species are therefore employed to engineer NiPt–Mo2C active site pairs, which can be encapsulated in carbon cages, via an in-situ self-confinement strategy. Mass activity of Pt in NiPt–Mo2C@C toward HER is boosted to 11.3 A/mgPt, 33 times higher than that of Pt/C. Similarly, MOR catalytic activity of Pt in NiPt–Mo2C@C is also improved by 10.5 times and the DMFC maximum power density is hence improved by 9-fold. By considering the great stability, NiPt–Mo2C@C exhibits great practical application potential in DMFCs and water electrolysers.

The methanol decomposition reaction has gained substantial attention due to the wide range of applications that its intermediates offer. In this work, methanol (CH3OH) decomposition on Copper-embedded graphene (CuG) surface has been investigated via density functional theory with Grimme-D2 dispersion correction. The charge density of the CuG surface has been analyzed and the redistribution of the electron density of the surface has been represented via the electron density difference (EDD) map. Moreover, the decomposition reaction mechanism of CH3OH on the CuG surface through the cleavage of C–H, O–H and C–O bonds has been investigated in detail. In the initial state, the C–O and O–H bonds of CH3OH have similar activation barriers, thereby the adsorption and degradation mechanism of the intermediate states arising through O–H bond cleavage on the CuG surface has been investigated. In addition, the charge density calculations of the transition state geometries have been conducted and examined with EDD maps. The results have revealed that the previously adsorbed oxygen molecule exhibited high catalytic activity towards O–H decomposition compared to the bare surface. The CuG surface has offered higher activity on the C–H bonds compared to the C–O bonds of the intermediate states generated by CH3OH decomposition. The results revealed that the proposed CuG structure can be utilized as an alternative electrode catalyst that can prevent the CO poisoning issue in direct methanol fuel cells. © 2021 Hydrogen Energy Publications LLC

A particular attention should be paid to isolation, characterization, and assessment of bioactive flavonoids, especially for anti-arthritic activity. The slurry of adsorbent (silica gel; 60–120 lattice) was blended in n-hexane to form a uniform slurry, and this was then employed as a fixed-stage adsorbent. Butanolic solution (10 g) was dissolved in the minimum volume of butanol, and then adsorbed on silica gel (60–120 mesh) while still wet. The wet powder was then dried, and the separated liquid phase was collected and applied to the column to try to isolate possible phytoconstituents. A whole plate full of fractions was monitored simultaneously on a TLC plate with a mixture of chloroform:methanol:water (68:30:02) as the solvent system. Six fractions (F1-F6) were generated after the colours of F1 and F2 were mixed next to each other, and after Rf was discovered in F3. A separate group of six animals was created for the survey, which was made up of five treatment groups and one control group. It was concluded that yellow crystalline solid luteolin was obtained as a result, with the Shinoda test confirming that it was a flavonoid. The absorption of luteolin was discovered to be in an aqueous alkaline solution. There were five different resonances, occurring at different frequencies, in the 400 MHz 1H NMR spectrum: 7.00 (d, J = 13.5 Hz, 2H), 6.73 (s, 1H), 6.56 (s, 1H), 6.18 (s, 1H), 6.05 (s, 1H), 4.78 (s, 1H), 4.24 (s, 1H), 3.81 (s, 1H) (s, 1H). Inhibiting arthritic inflammation at doses of 40 mg/kg (luteolin) was significant (P

In this work, a novel Ni–Cu/Al2O3 catalyst is used to trigger the partial oxidation of methanol (POM) for hydrogen production. This reaction system also employed ultrasonic sprays to aid in dispersing methanol fuel. The prepared catalyst is analyzed by scanning electron microscope (SEM), energy-dispersive X-ray (EDX) spectroscopy, and X-ray diffraction (XRD) to explore the catalyst's surface structure, elemental composition, and physical structure, respectively. The Box-Behnken design (BBD) of response surface methodology (RSM) is utilized for experimental design to achieve process optimization. The operating parameters comprise the O2/C molar ratio (0.5–0.7), preheating temperature (150–250 °C), and weight percent (wt%) of Ni (10–30%) in the catalyst. The results show that methanol conversion is 100% in all the operating conditions, while the reaction temperature for H2 production ranges from 160 to 750 °C, stemming from heat released by POM. The significance and suitability of operating conditions are also analyzed by analysis of variance (ANOVA). It indicates that the highest H2 yield is 2 mol (mol CH3OH)−1, occurring at O2/C = 0.5, preheating temperature = 150 °C, and Ni wt% = 10. Compared with the commercial h-BN-Pt/Al2O3 catalyst, the prepared Ni–Cu/Al2O3 catalysts have higher activity for H2 production. The O2/C ratio is the most influential factor in the H2 yield. Moreover, the interaction of the O2/C ratio and Ni content is sound, reflecting that changing Ni content in the catalyst will affect the trend of H2 yield under each O2/C.

Sustainable development based on the value-added utilization of furfural residues (FRs) is an effective way to achieve a profitable circular economy. This comprehensive work highlights the potential of FRs as precursor to prepare porous carbons for high performance supercapacitors (SCs). To improve the electrochemical performance of FR-based carbon materials, a facile route based on methanol pretreatment coupled with pre-carbonization and followed KOH activation is proposed. More defects could be obtained after methanol treatment, which is incline to optimize textural structure. The activated methanol treated FR-based carbon materials (AFRMs) possess high specific surface area (1753.5 m2 g−1), large pore volume (0.85 cm3 g−1), interconnected micro/mesoporous structure, which endow the AFRMs with good electrochemical performance in half-cell (326.1 F g−1 at 0.1 A g−1, 189.4 F g−1 at 50 A g−1 in 6 M KOH). The constructed symmetric SCs based on KOH, KOH–K3Fe(CN)6 and KOH-KI electrolyte deliver energy density up to 8.9, 9.9 and 10.6 Wh kg−1 with a capacitance retention of over 86% after 10,000 cycles. Furthermore, the self-discharge can be restrained by the addition of K3Fe(CN)6 and KI in KOH electrolyte. This study provides an effective approach for high-valued utilization of FR waste.

In the present study, we explored the effects of a novel xylanase from camel rumen metagenome (CrXyn) on wheat bran hydrolysis. CrXyn was heterologously expressed in Escherichia coli and showed maximum activity at 40 °C and pH 7.0. Furthermore, CrXyn exhibited preferential hydrolysis of xylan, but no obvious activity toward other substrates, including carboxymethylcellulose and Avicel. Using wheat straw xylan as a substrate, the Km and Vmax values for CrXyn were 5.98 g/L and 179.9 μmol xylose/min/mg protein, respectively. Mn

Several food dyes are known to induce amyloid fibrillation when interacting with proteins. Here, we studied the role of sunset yellow (SY) in the amyloid fibrillation of hen egg white lysozyme (HEWL) and characterized the changes using spectroscopy techniques. Turbidity results showed that SY dye induces aggregation in HEWL in concentrations dependent manner. The aggregation induced by SY dye is kinetically very fast, no lag phase was detected, and the kinetics process follows an isodesmic kinetics pathway. The SY-dye induce aggregates have cross-β secondary structure confirmed by far-UV CD measurements. The effect of salts and solvents was also seen on SY-induced aggregates. Turbidity, far-UV CD, and kinetics results suggest that certain concentrations of NaCl and (NH

Rational design of hybrid electrocatalysts of nanostructured non-precious metals/metal compound on highly conductive substrates is significant to enhance oxygen reduction activity for clean energy conversion. However, the limited exposure of active sites and sluggish mass transport on electrode trade-off the intrinsic performance of electrocatalyst. Herein, we report a strategic method to fabricate electrocatalyst with well-dispersed iron-based mixed nanoparticles embedding in nitrogen-doped carbon nanofibers (Fe-Fe3C/Fe3N@NCNFs) and demonstrate desired properties of the material, such as hierarchically porous structure, large specific surface area, and well-dispersion of mixed nanoparticles. The Fe-Fe3C/Fe3N@NCNFs electrocatalyst also exhibits high-performed activity in oxygen reduction reaction (ORR) with high onset potential of 0.998 V and half wave potential of 0.85 V, as well as high stability and methanol tolerance, which is even superior to benchmark performance of commercial Pt/C. In addition, a zinc-air battery assembled with Fe-Fe3C/Fe3N@NCNFs as the air cathode shows high open-circuit voltage (1.466 V), high specific capacities (778 mA h g−1 at 5 mA cm−2), excellent reversibility and stability. The remarkable improvement of electrocatalytic performance validates paramount advantages, attributing from the inter-connected conduction network and well-dispersed active sites on carbon nanofiber surface, over mass transfer process and maximizing exposure of catalytic sites

The hydrophobic and spherical PDVB-x-MeCN (x: molar ratio of p-styrene sulfonate/divinylbenzene; x=0.0, 0.1, 0.3, 0.5, and 1.0) catalyst was synthesized via polymerization and the ion-exchange process. Moreover, the hydrophobic property of PDVB-x-MeCN with high contact angles (> 124.0∘) was directly observed with a contact angle analyzer. The most appropriate x value of PDVB-x-MeCN for free fatty acid (FFA) removal and biodiesel production was 0.5, which was identified with gas chromatography (GC). During a 6-h transesterification-esterification, FFA removal and biodiesel yield of PDVB-0.5-MeCN reached 83.2% and 83.3%, respectively, at a ratio 45/1 (v/v) of methanol/palmitic acid mixture, approaching that of the Amberlyst 15 ones (83.4%). On the basis of these results, waste oils containing FFA can be transesterified efficiently from triglycerides and FFA into biodiesel.

The unveiling of MOF growth mechanism is hampered by the lack of fundamental knowledge about the very early stage of nucleation, especially the form and ratio of molecular species in the solution for crystal growth. Herein, we report the detection of growth species for a series of MOFs with mono-linker, Cu-MOF-2-BDC and Cu-MOF-2-NDC, and two linkers, MTV-MOF-2-(C4H4)x, by high resolution ESI-MS, where a large variety of Cu-containing species are identified unambiguously. The solvent molecules such as H2O, methanol and DMF participate in the formation of these species, other than ethanol. Furthermore, in the growth solution of MTV-MOF-2-(C4H4)x, growth species containing two different organic linkers are observed. The feeding ratio is not the only factor controlling the distribution of growth species for MTV-MOFs, but also the solvent involves in coordination, an aspect usually overlooked previously.

The catalytic properties of bifunctional ZSM-5@t-ZrO2 catalyst for methanol thiolation were revealed by using methanol and H2S as probe molecules. Taking the ZSM-5/t-ZrO2 physically-blended catalyst, pure ZSM-5 and t-ZrO2 as control catalysts, we investigated the characteristics of adsorption and transformation of different reaction molecules on or over different catalysts by combination of in-situ diffuse reflectance Fourier transform infrared spectroscopy (Drifts) and a variety of techniques including XRD, XPS, XRF, FT-IR, N2 adsorption-desorption, CO2/NH3-TPD, and DSC. The results showed that the synergistic effect of acid sites between ZSM-5 phase and t-ZrO2 phase in the bifunctional catalyst enhanced the adsorption and dissociation of methanol molecules, while the base sites in t-ZrO2 phase were mainly responsible for the adsorption and dissociation of H2S molecules. Due to the small specific surface area of pure t-ZrO2 catalyst, precursor species for sulfur deposition and carbon deposition were easily formed. Presulfurization could improve the initial activity of methanol thiolation and shorten the induction period. The dissociation of H2S at the base sites was the rate-determining step of the bimolecular reaction, and the appropriate increase of base sites in the bifunctional components could construct the matching formation rate of sulfhydryl and methoxy groups. At the same time, the special composite structure and meso-microporous system of ZSM-5@t-ZrO2 could effectively reduce the formation rate of carbon and sulfur deposits.

Methanol, a versatile chemical, fuel additive and potential H2 carrier, has attracted great attention. Despite of the wide industrialization, improvement of Cu-based methanol-synthesis catalysts is highly anticipated. Accordingly, a series of Cu/ZnO/Al2O3 with designed precursor structures were prepared, and its structure–function relationship was investigated to make progress on this area. Results showed the catalyst derived from highly zinc-substituted malachite demonstrated the best catalytic performance in this work. It was found that the well-behaved catalyst possessed relatively high Cu specific surface area and exposed Cu concentration, and the well Cu/ZnO synergy. CuZn alloy was found by In-situ XRD tests, and its effect on the catalyst's thermostability was discussed. Fractional precipitation, which facilitated the Cu2+ substitution by Zn2+ in malachite lattice, could be an efficient preparation method of the Cu/ZnO/Al2O3 catalyst.

A series of Pt/CeO2 (5 wt%) and bimetallic Cu-Pt/CeO2 (4 wt% Cu and 1 wt%) catalysts supported on different CeO2 nano shapes (polyhedra, rods, and cubes) were studied as catalytic systems for hydrogen production from the methanol decomposition (MD) reaction. Supports were prepared by hydrothermal approach and the active phase was incorporated by wet impregnation. Materials were characterized by SEM, HRTEM-STEM, N2 adsorption, EDS, XRD, Raman spectroscopy, H2-TPR, and CO-DRIFTS. The catalytic properties for MD reaction were studied as a function of temperature in the 100–450 °C range and as a function of time on-stream for 24 h at 350 °C. Despite the high methanol conversion presented by the Pt/CeO2 catalysts, more important in polyhedra and rods, these catalysts exhibited a low hydrogen yield. Differences in the properties of bimetallic Cu-Pt/CeO2 samples were established to be support-morphology-dependent, and the dispersion of copper and the ceria reducibility were superior in samples supported on polyhedra and rods as in the case of platinum catalysts. An improvement of the oxygen vacancies in the bimetallic system was also observed, as a result of the close interaction between copper and ceria. TOF values indicated that catalytic performances are promoted not only by the size of the active phase nanoparticles, but also by the facet predominantly exposed by ceria. The formation of bimetallic phase and the presence of surface Cu-Pt alloy sites in the rod-shaped sample accounted for the slightly better methanol conversion in the stability tests. The H2 yield in the bimetallic samples was superior compared to platinum, which makes them suitable candidates for the hydrogen production from the methanol decomposition.

Conversion of methanol to light olefins (MTO) using SAPO-34 molecular-sieve as the reaction catalyst was studied in a fluidized bed reactor within the temperature range of 400–550 °C by 50 °C increments and under 50, 66.6 and 90 vol% of methanol in the feed, diluted with water or an inert. SAPO-34-based catalyst was prepared by agglomeration with clay and alumina to allow proper fluidization. Catalytic results show the highest olefin yield for 500 °C and a reduction in catalyst deactivation for 1:1 methanol:water molar ration in the feed.

To modulate the acid properties of Sn-SBA-15-PrSO3H materials, the synthesis of heterogeneous Sn-SBA-15 catalysts modified with –PrSO3H groups was performed using the sol-gel method. This method enabled the integration of Sn in the structure of SBA-15, which was achieved by replacing Si+4 with Sn+4 ions, or by generating small amounts of SnO2 nanoparticles in octahedral coordination on the surface of the material. Incorporation of the –PrSO3H groups into the Sn-SBA-15 catalysts results in a significant increase in Bronsted and, to a lesser extent, Lewis acid sites. The relative concentration of Bronsted to Lewis acid sites was approximately 4:1. This improvement in the acid properties of the catalysts, led to an increase in the reaction rate for the esterification of oleic acid with methanol, achieving conversions that reach 96% at 100 °C after 2 h of reaction. The most favorable synthesis conditions were observed when the highest concentration of acid was used in the synthesis gel (1.1 M). This is due to the higher production of Sn+4 tetrahedral species in the SBA-15 structure and better integration of the -PrSO3H groups into the materials, which are mainly related to Bronsted acid sites. Finally, a linear relationship was established between the concentration of Bronsted acid sites in the catalyst and the catalytic activity for the oleic acid esterification and a second-order reversible model satisfactorily reproduces the experimental kinetic data.

Violacein, a blue-violet compound with a wide range of beneficial bioactivities, is an attractive product for microbial production. Currently, violacein production has been demonstrated in several sugar heterotrophs through metabolic engineering; however, the cost of production remains an obstacle for business ventures. To address this issue, the development of host strains that can utilize inexpensive alternative substrates to reduce production costs would enable the commercialization of violacein. In this study, we engineered a facultative methylotroph, Methylorubrum extorquens AM1, to develop a methanol-based platform for violacein production. By optimizing expression vectors as well as inducer concentrations, 11.7 mg/L violacein production was first demonstrated using methanol as the sole substrate. Considering that unidentified bottlenecks for violacein biosynthesis in the shikimate pathway of M. extorquens AM1 would be difficult to address using generic metabolic engineering approaches, random mutagenesis and site-directed mutagenesis were implemented, and a 2-fold improvement in violacein production was achieved. Finally, by co-utilization of methanol and acetate, a remarkable enhancement of violacein production to 118 mg/L was achieved. Our results establish a platform strain for violacein production from non-sugar feedstocks, which may contribute to the development of an economically efficient large-scale fermentation system for violacein production.

Concerns regarding food security arise from population growth, global warming, and reduction in arable land. With advances in synthetic biology, food production by microbes is considered to be a promising alternative that would allow rapid food production in an environmentally friendly manner. Moreover, synthetic biology can be adopted to the production of healthier or specifically designed food ingredients (e.g., high-value proteins, lipids, and vitamins) and broaden the utilization of feedstocks (e.g., methanol and CO

Toads belonging to the Bufonidae family have a pair of paratoid glands that store highly toxic a biological secretion with varied chemical composition, that act as a chemical defense against microbial infections and predators. The paratoid gland secretion (PGS) of bufonids is rich in bioactive steroids, alkaloids, proteins, bufadienolides and bufotoxins. In the present investigation we performed a systematic analysis of the chemical profile of PGS obtained from the Bufonidae toad Rhinella jimi ("Cururu" toad) collected at three different regions of Piauí state, Northeastern Brazil. Our aim was to investigate the PGS variation related to the season of animals collection, geographic distribution and gender of the animals. The methanolic extracts of PGS were analyzed by UPLC-QToF-MS/MS. Principal component analysis (PCA) were applied to the data set obtained by the UPLC-QToF-MS/MS analyses. Among 23 compounds identified, dehydrobufotenine, suberoyl arginine, 3-(N-suberoyl-argininyl) telocinobufagin, 3-(N-suberoyl-argininyl) marinobufagin, telocinobufagin, marinobufagin and 3-(N-suberoyl-argininyl) bufalin were detected in all PGS. Minimal variations in the composition of paratoid secretions of R. jimi were observed related to distinct geographical and seasonal parameters. R. jimi female animals presented the most diverse chemical composition in its PGS. With this comparative study, unprecedented for the species, it was possible to observe that the secretions of the paratoid glands produced by R. jimi from different regions of the state of Piauí, at different times of the year, presented consistent chemical composition, with discrete particularities in the number and nature chemistry of its constituents.

The synthesis of polyoxymethylene dimethyl ethers as an ideal diesel fuel additive is the current hot topic of modern petrochemical industry for their expedient properties in mitigating air pollutants emission during combustion. In this work, a series of spherical sulfated zirconia catalysts were prepared by a one-pot hydrothermal method assisted with surfactant cetyltrimethylammonium bromide (CTAB). The prepared sulfated zirconia catalysts were used to catalyze PODEn synthesis from methanol and formaldehyde solution. Various characterization (XRD, BET, SEM, TGA, NH3-TPD, FTIR, and Py-IR) were employed to elaborate the structure-activity relationship of the studied catalytic system. The results demonstrated that S/Zr molar ratio in precursor solution played an effective role on catalyst morphology and acidic properties, where the weak Bronsted acid sites and strong Lewis acid sites were favorable to the conversion of methanol and formation of long-chain PODEn, respectively. The reaction parameters such as catalyst amount, molar ratio of FA/MeOH, reaction time, temperature and pressure were optimized. The speculated reaction pathway for PODEn synthesis was proposed based on the synergy of Bronsted and Lewis acid sites, which suggested that Bronsted and Lewis acid sites might be advantageous to the activation of polyoxymethylene hemiformals [CH3(OCH2)nOH] and methylene glycol (HOCH2OH), respectively.

For the first time, the present work shows a combined theoretical and experimental analysis of the preferred adsorption sites for both methanol and methoxy species over Cu, Pt, and bimetallic Cu-Pt clusters - up to 5 atoms in size - supported on CeO2(111) as model systems. DFT+U calculations compared to methanol adsorption experiments followed by DRIFT spectroscopy over Cu, Pt, and bimetallic Cu-Pt nanoparticles supported over CeO2 octahedra, exposing only {111} crystal planes. From our DFT+U calculations, we found that methanol adsorption over the CuPt/CeO2(111) system is slightly favored, compared to the pristine CeO2(111) surface. Similarly, methoxy species formed through methanol dehydrogenation (CH3O- + H+) adsorb preferably over the metallic clusters, compared to the pristine oxide surface. This promotion is explained by the higher coordination of the methoxy species over the cluster, especially for those containing a higher amount of Cu atoms. This results highlights the oxidized Cu sites' role in the catalytic process, followed by the surface cerium atoms reduction of the support. The interaction of methanol with the substrate oxygen weakens the O-H bond, which results in a reduction in the energy barrier when the reaction occurs on the surface and interface, compared when this occurs exclusively on the metal cluster. However, after this step, the potential energy surface's depth suggests that methoxy species prefer to be adsorbed over the metal clusters. Experimentally, methanol was adsorbed over Cu, Pt, and bimetallic Cu-Pt nanoparticles supported over CeO2 {111}-octahedral particles. Through in-situ DRIFTS, bands related to adsorbed methanol and methoxy species were identified. A blue shift in all the bands was observed, related to metals’ influence in adsorbed species' vibrational mode. In the experimental spectra, new contributions in Cu-containing catalysts appeared, which were identified as adsorbed species over the metallic cluster and the interface, rationalized by calculated spectra.

In this work hydrotalcites with Ni/(Ni + Mg) ratios = 0.0, 0.33, 0.66 and ratio (Ni+Mg)/Al= 3, were synthesized. The hydrotalcite precursors were calcined and used as catalysts to study the effect of Ni content on the activity for transesterification of castor oil. The catalysts were characterized by physisorption of N2, X-Ray Diffraction (XRD), temperature programmed desorption (TPD) of CO2 and Fourier transform-infrared (FT-IR) spectroscopy of methanol adsorption. The reaction activity was measured by the production of each fatty acid methyl esters (FAMEs) using gas chromatography (GC). The highest activity and quantity of adsorbed methanol corresponds to the Ni2Mg1-C sample. It was found that the addition of nickel increases the number of sites of medium basic force. Methanol adsorption on the catalysts was studied by FT-IR and a relationship was established between the methoxy ions on the surface and the activity towards transesterification. Attenuated total reflectance infrared spectroscopy (ATR-IR) showed the existence of methoxy ions in solution when methanol was added to a calcined hydrotalcite and heated; with this data an alternative mechanism for basic heterogeneous catalysis was proposed. The reaction main steps are formation of a methoxy ion on the catalyst surface, followed by the reaction of the methoxy ion with triglycerides or fatty acid in the liquid phase.

We present a theoretical study using Halgren-Lipscomb algorithm assisted by DFT + U to determine the catalytic mechanism for hydrogen production by steam reforming of methanol over CeO2 and Ni/CeO2 model catalytic surfaces. Our main goal is to describe the physical-chemical interaction between nickel with CeO2 matrix support and catalytic conversion mechanism in response to experimental evidence. The results from transition energy states in ( 11 1 ¯ ) and ( 1 1 ¯ 1 ¯ ) CeO2 surfaces, with and without nickel cluster, indicate that process is favored when metallic nickel is contained, however, exothermic energies in bare CeO2 supports prior suggestions ascribing the particular catalytic activity enhancement of Ni/CeO2 nanorod for methanol steam reforming due a synergistic effect of the CeO2 exposed planes of the nanorods and Ni clusters. Our aim is to provide key data for the improvement and enhancement, in terms of efficiency and viability, the current production of hydrogen by methanol steam reforming by Ni/CeO2 systems.

Alcohol fuels oxidation plays a significant role in carbon sustainable cycling and high-performance catalyst with a strong anti-poisoning effect is desired. Herein, Pt-Ni alloy supported on the N-doped graphene aerogel synthesized by simple freeze-drying and annealing was demonstrated to have such catalytic ability for alcohol fuel oxidation. Pt-Ni alloy particles were found uniformly dispersed over the surface of 3D N-doped graphene aerogel. High anti-poisoning ability for CO-like intermediates oxidation was demonstrated by the CO-stripping experiment. The as-prepared catalyst was found to have outstanding catalytic performance for methanol and ethanol oxidation with high catalytic activity, stability and catalytic kinetics. Compared to the control samples, the improved catalytic ability could be due to the presence of oxophilic Ni species and the support effect of 3D N-doped graphene aerogel that combined multi-advantages of large surface area, facile mass transfer, and abundant defects.

The success of catalytic schemes for the large-scale valorization of CO2 does not only depend on the development of active, selective and stable catalytic materials but also on the overall process design. Here we present a multidisciplinary study (from catalyst to plant and techno-economic/lifecycle analysis) for the production of green methanol from renewable H2 and CO2. We combine an in-depth kinetic analysis of one of the most promising recently reported methanol-synthesis catalysts (InCo) with a thorough process simulation and techno-economic assessment. We then perform a life cycle assessment of the simulated process to gauge the real environmental impact of green methanol production from CO2. Our results indicate that up to 1.75 ton of CO2 can be abated per ton of produced methanol only if renewable energy is used to run the process, while the sensitivity analysis suggest that either rock-bottom H2 prices (1.5 $ kg−1) or severe CO2 taxation (300 $ per ton) are needed for a profitable methanol plant. Besides, we herein highlight and analyze some critical bottlenecks of the process. Especial attention has been paid to the contribution of H2 to the overall plant costs, CH4 trace formation, and purity and costs of raw gases. In addition to providing important information for policy makers and industrialists, directions for catalyst (and therefore process) improvements are outlined., Journal of Energy Chemistry, 68

Single metal atoms immobilized on a carbon substrate are of great potential for enhancing the catalytic activities for oxygen reduction and methanol oxidation reactions (ORR/MOR) owing to the maximized atom utilization. Herein, single copper atoms (SCAs) are loaded on macro-porous nitrogen-doped carbon (Cu-NC) derived from zeolitic imidazolate framework-8 (ZIF-8), which are used as catalysts for ORR and Pt-supports for MOR. For ORR, the catalyst marked as Cu-NC-3 exhibits a higher peak potential of 0.87 V (vs. Reversible hydrogen electrode) than that of commercial Pt/C (0.83 V), mainly attributing to that the 3D macro-porous structure of Cu-NC-3 provides adequate space for uniform dispersion of SCAs as the main active species, and smooth diffusion pathways for fast transport of substances (O2, H2O), therefore reducing the overpotential and the intermediate (H2O2) generation to enhance ORR activity. For MOR, Pt-Cu-NC-3 has a higher mass activity of 1217.4 mA/mgPt than that of Pt/C (752.4 mA/mgPt), and its activity maintenance (decline of 27.6%) is also better than Pt/C (decline of 44.0%) after 5000 cyclic voltammetry (CV) cycles. The interactions between SCAs and Pt nanoparticles should facilitate the generation of OH− from water molecules, which can fast eliminate the adsorbed CO to recover the Pt active sites to improve MOR performance. This synthesis strategy affords a new inspiration to prepare single metal atoms loaded on ZIFs-derived macro-structure with diverse activities for ORR/MOR.

Mesoporous silica of MCM-41 type with cylindrical and spherical morphology was synthesized and modified with iron species by template ion-exchange (TIE) method. Methanol solutions of FeCl2 and [Fe3(OCOCH3)7·OH·2 H2O]NO3, used as iron precursors, resulted in deposition of this metal in highly dispersed and aggregated forms, respectively. The obtained samples were characterized with respect to chemical composition - iron loading and surfactant content in non-calcined silicas (ICP-OES, TG-DSC), texture (low-temperature N2 sorption, XRD), morphology (SEM-EDS), form and aggregation of deposited iron species (UV–vis DRS, XRD, SEM-EDS), surface acidity (NH3-TPD) and reducibility of deposited iron species (H2-TPR). Iron modified silicas presented a very good catalytic performance in the high-temperature NH3-SCR process (effective operation in the range of 350–475 °C), however the specific catalytic activity depends on the morphology of the silica samples as well as the form and aggregation of deposited iron species. Moreover, the reactions associated with the NH3-SCR process, such as NO to NO2 oxidation and direct ammonia oxidation were studied.

This article reviews the background, metabolism, clinical effects, and treatment of toxic alcohols, specifically ethylene glycol, methanol, diethylene glycol, propylene glycol, and isopropyl alcohol. This article also reviews the importance of an anion gap metabolic acidosis in relation to toxic alcohols and explores both the utility and the limitations of the osmol gap in patient management.

The heterogeneous nature of e-waste, which is a rich source of metals, polymers, glass fibres and ceramics, is troublesome. Multi-step processes are employed to effectively treat e-waste with minimum environmental impact. In this research, a subcritical to supercritical methanol environment was investigated to pre-treat e-waste, recovering non-metallic fractions and eventually concentrate metals from e-waste. Experiments were conducted in the temperature range of 150 °C to 300 °C at an autogenous pressure with initial atmospheric pressure. The mechanism of depolymerization was investigated by varying reaction time from 30 min to 240 min; solid to liquid ratio of 1:10 to 1:30 g/ml in a batch reactor under N

Studies on the degradation process of waste polyethylene terephthalate (PET) have become increasingly mature, but there are relatively few studies on the separation of degradation products. The products contain many components and the separation of which is difficult. Therefore, the study on phase equilibrium thermodynamics of bis-2-hydroxyethyl terephthalate (BHET) is of great theoretical significance and practical value to provide basic data for the BHET crystallization separation. In this work, the degraded products were purified and characterized. The solubility of BHET in methanol, ethanol, ethylene glycol, water and the mixture of ethylene glycol+water were determined by static method. The experimental results were correlated with different models, such as IS model, λh equation, Apelblat equation and NRTL model. Based on the Van't Hoff equation, the mixing Gibbs energy, enthalpy and entropy were calculated. From this work, the basic data which can be used to guide the crystallization process of BHET were obtained, including solubility data, correlation model and thermodynamic properties

By combining 5,10,15,20-tetra(4-chlorine)phenylporphyrin (TClPP) and α-Keggin polyoxometalate H5PV2Mo10O40 (H5PVMo) via a simple ion-exchange method, an organic-inorganic hybrid material [C44H28N4Cl4]1.5[H2PMo10V2O40]•2C2H6O (H2TClPP-H2PVMo) was prepared and thoroughly characterized by a variety of techniques. The homogeneous photocatalytic degradation of 2-chloroethyl ethyl sulfide (CEES) (5 μL) by H2TClPP-H2PVMo (1 × 10−6 mol/L) was studied in methanol and methanol-water mixed solvent (v/v = 1:1), in which the degradation rate of CEES reached 99.52% and 99.14%, respectively. The reaction followed first-order reaction kinetics, and the half-life and kinetic constant in methanol and the mixed solvent were respectively 33.0 min, -0.021 min−1 and 15.7 min, -0.043 min−1. Mechanism analysis indicated that under visible light irradiation in the air, CEES was degraded via oxidation and alcoholysis/hydrolysis in methanol and the mixed solvent. O2•− and 1O2 generated by H2TClPP-H2PVMo selectively oxidized CEES into a non-toxic sulfoxide. Singlet oxygen capture experiments showed that H2TClPP-H2PVMo (Φ = 0.73) had a higher quantum yield of singlet oxygen than TClPP (Φ = 0.35) under an air atmosphere and visible light irradiation.

Pancreatic lipase is the key enzyme for lipid digestion. Inhibition of this enzyme can reduce lipid absorption and prevent obesity disease. A methanol extract prepared from the whole plant of Dendrobium harveyanum exhibited strong anti-lipase effect. Chromatographic separation of this plant results in the isolation of 5 known compounds including 3,4-dihydroxy-5,4′-dimethoxybibenzyl (1), dendrofalconerol A (2), dendrofalconerol B (3), daucosterol (4) and dendrocandin B (5). The structures were determined by analysis of their spectroscopic data. All compounds were evaluated for their lipase and α-glucosidase inhibitory activities. Dendrofalconerol B (3) showed noticeable lipase and α-glucosidase inhibitory effects when compared with the positive controls. Dendrofalconerol B was further studied and found to show strong anti-adipogenic activity through the suppression of PPARγ and C/EBPα expression, resulting in the reduction of cellular lipid accumulation in preadipocyte 3T3-L1 cells. Taken together, these results strongly support the potential development of dendrofalconerol B as a safe and effective treatment for metabolic diseases.

A modified technique of epitaxial growth employed to produce “core-shell” catalysts coating microporous ZSM-5 with a layer of Silicalite-1 is presented in this paper. The aim was to passivate surface acidity of a ZSM-5 zeolite, in the view of potential limitation of surface effect generally responsible for coke formation. Core-shell catalysts have been synthetised starting from a ZSM-5 core with Si/Al=25. Two different hydrothermal Silicalite-1 synthesis were performed: one using the ZSM-5 as made-form and the second using the ZSM-5 H+-form as core. This allowed to investigate the effect of the organic template, filling the pores of the core, on the shell growth mechanism. Coating procedure lasted 24 h and it was repeated twice to increase Silicalite-1 thickness. All catalysts were tested for the reaction of methanol dehydration to DME in an atmospheric system at 180-240° and time on stream tests were carried out to analyse the stability of the samples. Considering the catalytic performances in terms of methanol conversion, DME selectivity and deactivation, core-shell catalysts, synthetized using an as-made form core, exhibited interesting performances, resulting from a more controlled growth of the passivating layer. These materials could constitute valid option for hybrid (Metal-Zeolite) catalyst, where the reduction of surface acidity could better stabilise the metallic function.

It is difficult to separate the methanol and hydrocarbons in the propylene oxide (PO) purification process due to their forming azeotrope. As for this, a novel PO separation process, in that the deionized water is employed as extractant and 1,2-propylene glycol (MPG) that is formed from the PO hydrolysis reaction is recovered, is presented in this work. The salient feature of this process is that both the non-catalyzed reactions of PO hydrolysis to form MPG and dipropylene glycol (DPG) are simultaneously considered and MPG by-product with high purity is obtained in virtue of the deionized water as reflux liquid and side take-off in MPG column. In addition, the ionic liquid (IL) extractant is screened through the conductor-like screening model for segment activity coefficient (COSMO-SAC) and the comparisons of separation efficiency between the IL and normal octane (nC8) extractant for the separation of PO and 2-methylpentane are made. With the non-random two-liquid (NRTL) thermodynamic model, the simulation and optimization design for the full flow sheet are performed and the effects of the key operation parameters such as solvent ratio, theoretical stages, feeding stage etc. on separation efficiency are detailedly discussed. The results show that the mass purity and the mass yield of PO can be up to 99.99% and 99.0%, and the condenser duty, reboiler duty and PO loss in the process with IL extractant can be decreased by 69.66%, 30.21% and 78.86% compared to ones with nC8. The total annual cost (TAC) calculation also suggests that the TAC would be significantly reduced if using IL in replace of nC8 in the investigated process. The presented results would provide a useful guide for improving the quality of PO product and the economic efficiency of industrial plant.

Developing an environmental-friendly and highly active catalyst in transesterification for biodiesel production is of great importance for a more economic biodisel process. Herein, we reported that waste eggshells were used to adsorb Au(III) in water and convert the Au(III)-polluted eggshells into the functional nanocatalyst-CaO/Au for the transesterification reaction between soybean oil and methanol to the preparation of biodiesel. By coupling of CaO and Au nanoparticles, CaO/Au nanoparticles showed superior catalytic activity for the transesterification reaction between soybean oil and methanol. An optimum performance was observed over CaO/Au nanocomposites in a methanol-oil molar ratio at 12: 1 with catalyst content of 1.0 wt% at 70 °C for 3 h. Besides, the catalytic activity of CaO/Au nanocatalyst was almost unchanged after recycling for 5 times and the yield of biodiesel still kept at 88.9%. The proof-of concept study provided us a sustainable method for utilization of waste eggshells to remedy the metal ions-polluted wastewater and the synthesis of functional nanocomposite for biodiesel production, show great potential application of waste eggshell in adsorption and catalytic reactions.

Designing highly efficient non-precious based electrocatalysts for oxygen reduction reaction (ORR) is of significance for the rapid development of metal-air batteries. Herein, a hydrothermal-pyrolysis method is employed to fabricate Fe, N co-doped porous carbon materials as effective ORR electrocatalyst through adopting graphitic carbon nitride (g-C3N4) as both the self-sacrificial templates and N sources. The g-C3N4 provides a high concentration of unsaturated pyridine-type N to coordinate with iron to form Fe-N active sites. Through adjusting the Fe doping amounts, it is proved that appropriate Fe doping content is conducive to the construction of abundant defects and active sites of Fe-N. The as-prepared catalyst exhibits superior electrocatalytic ORR performance in alkaline media with half-wave potential (E1/2 = 0.82 V) and onset potential (Eonset = 0.95 V), equivalent to the commercial Pt/C catalyst. Moreover, there is almost no activity loss after 10 k continuous cyclic voltammetry cycles and methanol tolerance, indicating the excellent durability and superior methanol tolerance. Remarkably, when assembled as the cathode in a Zn-air battery, the device displays a power density of 99 mW/cm2, an open-circuit potential of 1.48 V and long-term discharge-charge cycling stability, indicating the promising potential to substitute the Pt catalyst for practical application.

The need to develop specific-morphology nanomaterials to produce dimethyl ether (DME), a promissory alternative fuel, by the catalytic methanol dehydration has triggered extensive research to synthesize novel materials. In this work mesoporous Al-MCM-41 nanospheres with variable size (35−90 nm) were synthesized by the sol-gel method. The size of the Al-MCM-41 nanospheres was controlled by adjustable NaOH/TEOS ratio (0.2−0.5). The Al-MCM-41 nanospheres were characterized by TPD, TEM, XRD, EDX, XPS and N2-physisorption. According to the characterization results the Al ions were successfully incorporated in the MCM-41 framework and the Al-MCM-41 nanospheres showed hexagonal and mesoporous structure. Additionally, it was observed that the higher the NaOH/TEOS ratio the smaller size of the nanosphere and, smaller Al-MCM-41 nanospheres presented more amount of medium acidic sites on its surface. The catalytic activity results showed that all samples tested reached 100% of selectivity towards DME. The smallest Al-MCM-41 nanospheres achieved 78% of DME yield at 300 °C and good catalytic activity performance below to 300 °C. The stability of the fresh and regenerated Al-MCM-41 nanospheres was evaluated for 48 h time-on-stream. High values of DME yield (> 60%) were maintained during 48 h time-on-stream showing the possibility for recycling the material.

Green and economical CO2 utilization is significant for CO2 emission reduction and energy development. Here, the 1D Mo2C nanowires with dominant (101) crystal surfaces were modified by the deposition of atomic functional components Rh and K. While unmodified β­Mo2C could only convert CO2 to methanol, the designed catalyst of K0.2Rh0.2/β-Mo2C exhibited up to 72.1% of ethanol selectivity at 150 °C. It was observed that the atomically dispersed Rh could form the bifunctional active centres with the active carrier β­Mo2C with the synergistic effects to achieve highly specific controlled C–C coupling. By promoting the CO2 adsorption and activation, the introduction of an alkali metal (K) mainly regulated the balanced performance of the two active centres, which in turn improved the hydrogenation selectivity. Overall, the controlled modification of β­Mo2C provides a new design strategy for the highly efficient, low-temperature hydrogenation of CO2 to ethanol with single-atom catalysts, which provides an excellent example for the rational design of the complex catalysts.

A kinetic model for the direct synthesis of dimethyl ether (DME) from syngas over a hybridized Cu/ZnO/Al2O3/ferrierite (CZA/FER) catalyst was developed. Kinetic parameters including reaction rate and equilibrium constants were estimated by fitting experimental data for the hybrid catalyst, and these were compared with the reported values for conventional catalysts. High activation energies for the hybrid CZA/FER catalyst showed that the methanol synthesis step may have more control over the rate than the methanol dehydration step. This may be attributed to the core-shell structure of the hybrid catalyst in such a way that the diffusion resistance plausibly plays an important role in the kinetics; this feature was reflected in our estimated kinetic parameters. Using the developed kinetic model, a temperature between 200 and 220 °C was determined for thermal energy efficiency, and a further analysis provided the optimal range of the total pressure and space velocity.

Strombidae is one of the major molluscan families in Sudan and due to their opercula, has tremendous economic value. In traditional Sudanese homemade perfumes and body care cosmetics, Strombidae family operculum is one of the main ingredients. Their fumigation generates a charming odor preferred by Sudanese people, used for body smoke baths by married women. Moreover, these fumes are believed to treat several gynecological disorders. In this study, we attempted to confirm the presence of volatiles with pleasant odors and compounds with pharmaceutical importance in the Strombidae opercula. Volatiles from the smoke and soak extracts of the burned opercula were analyzed using gas chromatography-mass spectrometry (GC-MS). Furthermore, polar components from the methanol extract of opercula powder were isolated using high-performance liquid chromatography (HPLC) and identified by nuclear magnetic resonance (NMR), electrospray ionization mass spectrometry (ESI-MS), and UV spectra. The elemental and metal contents were analyzed using inductively coupled plasma-mass spectrometry (ICP-MS). GC-MS analysis revealed several phenols, aldehydes, ketones, and other functional fragrant and volatile constituents. Further, two compounds were purified from the methanol extract of Strombidae opercula, and named compounds B and D, which were identified as cyclo-(Tyr-Gly) and 4-hydroxybenzaldehyde, respectively. ICP-MS analysis revealed the presence of various elements and metals at different levels. These findings support the historical and traditional practices and usage of the Strombidae opercula in therapeutic and esthetic products. The opercula contains many biologically active compounds and produces smoke containing volatile scent compounds, which might provide alternative pharmaceuticals and cosmetic ingredients that can cooperate to improve the manufacturing of numerous medical products.

The transformations of CO2 molecules into valuable products are of increasing interest due to the negative impact of anthropogenic CO2 emissions on global warming. The CO2-to-methanol hydrogenation is an economically profitable reaction of carbon fixation, but it still steps away from widespread industrialization because of the lack of efficient and selective catalysts. Recently, single-atom alloy (SAA) catalysts have been developed to work remarkably in CO2 hydrogenation reactions. Doping isolated single atoms into metallic catalyst can dramatically alter the catalytic performance of the host. We have performed a screening discovery on Ru and 6 RuX (X = Fe, Co, Ni, Cu, Ir and Pt) SAAs using density functional theory (DFT) computations. We considered 13 possible elementary reactions in 4 possible reaction pathways on Ru and all RuX surfaces. In the computed mechanisms, we found that the formation of *H2COOH and *HCOO intermediates plays a critical role in determining catalysts’ activities. Doping Co and Pt isolated single atoms into Ru surface can thermodynamically and kinetically facilitate these intermediates formation processes, eventually promoting the production of methanol. The combination of weak binding and enhanced charge redistribution on RuCo and RuPt surfaces give them improved catalytic activities over pure Ru. This work will ultimately facilitate the discovery and development of SAAs for CO2 to methanol, serving as guidance to experiments and theoreticians alike.

Esterification reaction is a pretreatment method used to reduce the free fatty acids (FFA) content in acidified oil. Normally, the presence of high FFA content contributes to saponification reaction and thus, decreases the yield of fatty acid methyl ester (FAME) produced. The usage of ion exchange resin (IER) as a catalyst has been widely used to reduce the FFA content because they can catalyse the esterification reaction under mild conditions. However, current IER are having low acidic acid sites, moderate surface area and low thermal stability. This study focuses on the esterification process of FFA in simulated used cooking oil (SUCO) using self-synthesised sulphonated hypercrosslinked exchange resin (SHER) as catalyst. This study was divided into two stages. The first stage focused on the synthesis and characterisation of SHER, prepared via non-aqueous dispersion (NAD) technique followed by sulphonation process. The effect of monomer/co-monomer concentration, crosslinker concentration, Lewis acid catalyst ratio, and sulphonation reagent on the physicochemical characterisation of the resin were investigated to produce the best catalyst beads. From this stage, the best SHER beads has successfully developed at the condition of 80% of styrene (St), 20% of vinylbenzyl chloride (VBC), 1wt% of ethylene glycol dimethacrylate (EGDMA), 1:1 of molar ratio of FeCl3: CH2Cl, and 4wt% of sulphuric acid. The newly developed SHER possesses a high surface porosity with approximately 836 m2 g-1 surface area. It has the ability to withstand high temperature up to 398°C with the acidity values at 5.1 mmol g-1. The second stage concentrated on the performance of SHER in the esterification of FFA using SUCO as a feedstock. The esterification reaction was carried out in a batch system and the effect of various parameters such as catalyst loading, temperature, and molar ratio were investigated. SHER had successfully catalysed the reaction and achieved 97% of FFA conversion at 150 rpm, 5wt% of catalyst loading, 60°C, and 12:1 of methanol (MeOH) to SUCO molar ratio. During reusability study, the catalyst activity decreased for about 40% after five cycles of reaction. The decrease in FFA conversion was due to the pore blockage during the reaction and hence, blocked the reactants from accessing the active sites. The performance of SHER was compared with selected commercial resins (i.e., Diaion RCP145H, Diaion PK228LH, and Diaion SK1BH) and the experiments were conducted at the same reaction conditions. SHER showed the highest conversion and reaction rate compared to other catalysts. The excellence performance of SHER was due to the high amount of surface area, pore volume, sulphur content, and acidity owned by the SHER.

In this work, vanadium and lanthanum co-doped ZnO/CNTs (VL-ZnO/CNTs) composites of large surface area and enhanced light assimilation range were produced for boosted hydrogen evolution from water. The photocatalysts were investigated for their morphological, structural, optical and photocatalytical properties. The photocatalytic activity of the composites was evaluated in pure water and in a mixture of water and methanol under simulated sunlight and visible light illumination. Under simulated sunlight irradiation, the maximum hydrogen generation rate of 925 μmolh−1g−1 from a combination of water and methanol was attained, which is almost 7 times higher than hydrogen generation rate achieved with pure ZnO. The VL-ZnO/CNTs photocatalyst resulted in hydrogen production rate of 267 μmolh−1g−1 from the water-methanol medium when exposed to visible light. This rate was about 3.5 folds lower than that achieved under simulated sunlight illumination. This improvement in hydrogen production rate is attributed to large surface area, high photo-response, better separation/transportation of the charge carriers and synergistic impact of V, La and CNTs in the designed photocatalyst.

A novel solid Bronsted-Lewis acid catalyst La-PW-SiO2/SWCNTs was synthesized from the synergistic modification of H3PW12O40 (HPW) by single-walled carbon nanotubes functionalized with sidewall hydroxyl groups (SWCNTs–OH) and La3+ via sol-gel method. The freshly prepared catalyst was characterized by several methods, and the catalytic activity and stability of it were studied from the esterification of oleic acid and methanol. Results showed that the highest conversion of oleic acid was 93.1 wt% and maintained as high as 88.7 wt% after six cycles of La-PW-SiO2/SWCNTs. The high catalytic activity and stability of La-PW-SiO2/SWCNTs can be attributed to the strong electron withdrawing effect of La3+ on π bond of SWCNTs, because it can facilitate the formation of a large number of strong Lewis acid sites. Therefore, the reduction of catalytic activity of a solid acid catalyst due to the fact that hydration reaction of its Bronsted acid sites can be effectively reduced. La-PW-SiO2/SWCNTs can be an efficient and economical catalyst, because it shows good catalytic activity and stability.

Catalytic depolymerization of lignin has been investigated in the presence of egg shell derived CaO/TiO2 catalysts. Reaction was carried out for different reaction temperatures (250, 280 and 310 °C) at different reaction holding time at presence of N2 and H2 gas under ethanol, methanol and water solvent. Highest bio-oil yield was found with CaO/TiO2-800 catalyst in ethanol solvent under N2 (74.8 wt%), and H2 (82.8 wt%) environment compared to the water solvent. Under hydrogen environment very less amount of unreacted residue was produced. Bio-oil analysis showed that in under nitrogen environment catalytic depolymerization of lignin produced alkyl phenolic monomer compounds 68.0% with methoxy phenolic compounds 24.0%. Interestingly hydrogen promoted the deoxygenating and hydrogenation reaction which produced higher cyclohexane compounds 38.2% and aromatic hydrocarbon 19%. This is suggesting that the effectively breaking of β-O-4 bond by the catalysts which has an excellence character for the industrial application. Elemental analysis shows that hydrogen enhanced the bio-oil quality compared to the nitrogen environment. This work introduces new perspectives for the efficient production of functional compounds from lignin assisted by egg shell derived green catalysts.

A dendritic PdCu/Ce0.3Zr0.7O2 (PdCu/CZ-3) catalyst with uniform spherical morphology was prepared for boosting the catalytic performance of CO2 hydrogenation to methanol (MeOH). The open dendritic pore channels and small particle sizes could reduce not only the diffuse resistance of reactants and products but also increase the accessibility between the active sites (PdCu and oxygen vacancy) and the reactants (H2 and CO2). More spillover hydrogen could be generated due to the highly dispersed PdCu active metals over the PdCu/CZ-3 catalyst. PdCu/CZ-3 can stimulate the generation of more Ce3+ cations, which is beneficial to produce more oxygen vacancies on the surface of the CZ-3 composite. Spillover hydrogen and oxygen vacancy could promote the formate and methoxy routes over PdCu/CZ-3, the primary intermediates producing MeOH. PdCu/CZ-3 displayed the highest CO2 conversions (25.5 %), highest MeOH yield (6.4 %), highest PdCu-TOFMeOH (7.7 h-1) and superior 100 h long-term stability than those of other PdCu/CexZr1-xO2 analogs and the reference PdCu/CeO2 and PdCu/ZrO2 catalysts. Density functional theory (DFT) calculations and in situ DRIFTS were performed to investigate the CO2−MeOH hydrogenation mechanism.

To reduce greenhouse gas emission from oil and gas production, it is essential to better convert methane to useful chemicals (rather) than to flare it. Conversion of methane to liquid oxygenates (mainly methanol) has attracted extensive attention and countless efforts have been made; however, running this reaction in a green, efficient, and practical way has remained elusive. The novel catalyst and oxidants play a critical role in activating methane and converting it to oxygenates (methanol). In this review, the work of commonly used oxidants for methane partial oxidation have been summarized, in which, earth abundant oxidants, O2 and H2O are promising. Moreover, H2 or CO can activate O2 to produce H2O2 that catalyzes methane partial oxidation more efficiently and selectively than O2 or H2O. Therefore, the work of using reducing agent, such as CO and H2 have been reviewed, focusing on rational catalyst design that features multifunction (H2O2 production and CH4 activation). The novel catalyst design has advanced this reaction towards practicality with green oxidants and H2 using zeolites-based catalyst. Environmentally friendly zeolite preparation methods and novel two-dimensional (2D) zeolites that can reduce waste, improve synthesis and catalytical performance substantially are also reviewed in this work to provide insights for a more comprehensive approach to meet the environment protection needs.