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Hydrogenolysis of glycerol based on biomass is a possible route to obtain various valuable chemicals. Molecular hydrogen is a reactant in hydrogenolysis reactions. Optimizing hydrogen pressure can bring about a number of different benefits and other value added aspects to the process. In addition, hydrogen could also affect the catalyst surface and chemical characteristics which affect the catalyst activity. This study is focused on the influence of the pressure of hydrogen on the hydrogenolysis of glycerol using a 10Ni-30HSiW/α-Al 2 O 3. The catalysts of 10Ni-30HSiW/α-Al 2 O 3 were prepared using a wetness impregnation technique and the catalytic activity is tested in a batch reactor. The characterization of these catalysts were performed using different techniques such as NH 3 temperature programmed desorption (TPD), X-ray powder diffraction (XRD), Thermal gravimetric analysis (TGA), X-ray photoelectron spectroscopy (XPS) and Fourier transformed infrared spectroscopy (FT-IR). The study found that the hydrogen pressure influenced both the conversion of glycerol and the distribution of products. As the H 2 pressure increased, the selectivity to 1-propanol (1-PO) increased while the selectivities to acrolein, acetol and other products decrease. Interestingly the conversion of glycerol went through a maximum of 64.8% at 145 PSI of H 2 and decreased as the H 2 pressure increased. It was found that it is necessary to have high hydrogen pressure to maintain Ni in the metallic or zero oxidation state which accelerated the hydrogenation of acrolein to 1-PO and suppressed the formation of byproducts. However reduction of W6+ to a lower oxidation state (W4+) occurred under a high pressure of H 2 which reduces the acidity of the catalyst during the dehydration and decreased the conversion of glycerol. [Display omitted] • Molecular hydrogen is an important reactant in hydrogenolysis of glycerol. • Acidity plays an important role for the dehydration. • Ni plays an important role for the hydrogenation. • Hydrogen does not only affect the product distribution but it also affects the glycerol conversion owing to changes in the oxidation states of Ni and W in the catalyst. • High hydrogen pressure is required to maintain Ni in the metallic or zero oxidation state. • High hydrogen pressure reduce the acidity of the catalyst due to the reduction of W6+ to a lower oxidation state (W4+). [ABSTRACT FROM AUTHOR]

Abstract: A palladium-impregnated La0.75Sr0.25Cr0.5Mn0.5O3−δ /yttria-stabilized zirconia (LSCM/YSZ) composite anode is investigated for the direct utilization of methane and ethanol fuels in solid oxide fuel cells (SOFCs). Impregnation of Pd nanoparticles significantly enhances the electrocatalytic activity of LSCM/YSZ composite anodes for the methane and ethanol electrooxidation reaction. At 800°C, the maximum power density is increased by two and eight times with methane and ethanol fuels, respectively, for a cell with the Pd-impregnated LSCM/YSZ composite anode, as compared with that using a pure LSCM/YSZ anode. No carbon deposition is observed during the reaction of methane and ethanol fuels on the Pd-impregnated LSCM/YSZ composite anode. The results show the promises of nanostructured Pd-impregnated LSCM/YSZ composites as effective anodes for direct methane and ethanol SOFCs. [Copyright &y& Elsevier]

Abstract: A reactive distillation (RD) process directly intensified by an auxiliary reaction is presented. The methyl acetate (MeOAc) hydrolysis intensified by methanol (MeOH) dehydration is studied as an example where the latter serves as the auxiliary reaction. A residue curve maps (RCMs) is developed to analyze the mechanism of intensification for the case with two reactions and multiple components. The analysis of thermodynamics and RCMs reveals that the reaction of MeOH dehydration is the controlling step which limits the conversion of MeOAc. Based on the chemical equilibrium and kinetically controlled design, a novel process is developed to hydrolyze MeOAc and MeOH in the process of polyvinyl alcohol. Compared to traditional processes, no additional water is required to feed into the RD column and the process is significantly simplified. With equal mole of MeOAc and MeOH as feed and a set of pre-reactor, closely 100% conversion of MeOAc and MeOH can be achieved and high purity dimethyl ether and acetic acid are the products in the RD column. [Copyright &y& Elsevier]

Abstract: In order to screen ionic liquids (IL) as suitable solvents for the separation of benzene and cyclohexane, the extraction efficiency of ILs (12 cations and 22 anions) was estimated based on COSMO-RS predictions of infinite dilution activity coefficients of benzene and cyclohexane in different ILs..[C4mim][AlCl4] was found to be the most promising solvent. To provide deep insight on how the IL structure influences the extraction efficiency, molecular interactions between IL ions and benzene were determined from DFT calculations. Moreover, liquid–liquid equilibrium data of the ternary system benzene–cyclohexane—[C4mim][AlCl4] were experimentally determined and used to fit parameters of the NRTL activity coefficient model. Based on the NRTL model the continuous extraction process was simulated and compared with a reference process using sulfolane as solvent. For the extraction process using [C4mim][AlCl4], high cyclohexane product purity (99.65wt%) and high benzene recovery efficiency (98.03%) can be reached with at much lower energy consumption and higher product yield compared to conventional extraction solvents. In conclusion, the ionic liquid [C4mim][AlCl4] is a promising solvent for the extractive separation of benzene and cyclohexane. [Copyright &y& Elsevier]

Abstract: In order to screen ionic liquids (IL) as suitable solvents for the separation of benzene and cyclohexane, the extraction efficiency of ILs (12 cations and 22 anions) was estimated based on COSMO-RS predictions of infinite dilution activity coefficients of benzene and cyclohexane in different ILs..[C4mim][AlCl4] was found to be the most promising solvent. To provide deep insight on how the IL structure influences the extraction efficiency, molecular interactions between IL ions and benzene were determined from DFT calculations. Moreover, liquid–liquid equilibrium data of the ternary system benzene–cyclohexane—[C4mim][AlCl4] were experimentally determined and used to fit parameters of the NRTL activity coefficient model. Based on the NRTL model the continuous extraction process was simulated and compared with a reference process using sulfolane as solvent. For the extraction process using [C4mim][AlCl4], high cyclohexane product purity (99.65wt%) and high benzene recovery efficiency (98.03%) can be reached with at much lower energy consumption and higher product yield compared to conventional extraction solvents. In conclusion, the ionic liquid [C4mim][AlCl4] is a promising solvent for the extractive separation of benzene and cyclohexane. [Copyright &y& Elsevier]