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Abstract: Derived hydrotalcite catalysts, with different Ni loadings, were prepared and tested in aqueous-phase reforming of ethanol. Upon calcination of the hydrotalcite-like compounds, there was formation of MgO periclase-type phase, where both nickel and aluminum oxides are well dispersed. The mixed oxides showed only one reduction peak in temperature range of 900–1000°C. The catalytic tests were carried out in a batch reactor with an aqueous solution of 1wt.% ethanol at different temperatures (200, 230 and 250°C). The derived hydrotalcite catalysts showed high activity, with 65% of ethanol conversion at 230°C, high hydrogen selectivity and lower methane production than alumina supported nickel catalyst. [Copyright &y& Elsevier]

Abstract: In many reactions to produce biodiesel the glycerol represents 10 wt% of the total products therefore it is important to find an adequate destination of such byproduct. The catalytic hydrolysis of triglycerides is another way to produce biodiesel from fatty raw materials. This work shows the catalytic hydrolysis of triglycerides (soybean oil and tallow) with nickel (NiO) or palladium (PdO) catalysts supported on Al2O3 or SiO2. The results showed the direct conversion of in situ generated glycerol into hydrogen (H2) and carbon dioxide (CO2). The glycerol conversion was evaluated through the capacity to hydrogenate the unsaturated fatty acids leading to the formation of stearic acid (saturated compound). The catalyst, temperature and time were varied and evaluated in the experiments utilizing the two different kinds of raw materials (beef tallow and soybean oil). Selectivity and statistical planning studies were performed to optimize the formation of stearic acid as it is linked to the hydrogenation of unsaturated compounds by hydrogen generated from the glycerol liquid reforming. [Copyright &y& Elsevier]

Abstract: Esters of fatty acids, derived from vegetable oils or animal fats, and known as biodiesel, are a promising alternative diesel fuel regarding the limited resources of fossil fuels and the environmental concerns. In this work, methanolysis of soybean oil was investigated using Mg–Al hydrotalcites as heterogeneous catalyst, evaluating the effect of Mg/Al ratio on the basicity and catalytic activity for biodiesel production. The catalysts were prepared with Al/(Mg+Al) molar ratios of 0.20, 0.25 and 0.33, and characterized by X-ray diffraction (XRD), textural analysis (BET method) and temperature-programmed desorption of CO2 (CO2-TPD). When the reaction was carried out at 230°C with a methanol:soybean oil molar ratio of 13:1, a reaction time of 1h and a catalyst loading of 5wt.%, the oil conversion was 90% for the sample with Al/(Mg+Al) ratio of 0.33. This sample was the only one to show basic sites of medium strength. We also investigated the reuse of this catalyst, the effect of calcination temperature and made a comparison between refined and acidic oil. [Copyright &y& Elsevier]

Abstract: An essential requirement for the proton exchange membrane fuel cell (PEMFC) is to deliver clean H2 to the anode electrode, the kinetics of which are greatly hindered by traces of CO present from the upstream hydrocarbon reforming and water–gas shift processes. The removal of CO from hydrogen-rich stream to a PEMFC tolerant level, by selective oxidation (SELOX) of CO, has been studied over 1%Pt/Al2O3, 1%Pt-1%Sn/Al2O3, 1%Pt/Nb2O5 and 1%Pt-1%Sn/Nb2O5 catalysts. The Nb2O5-supported catalysts presented higher activity in SELOX reaction at low temperatures, but with lower CO selectivity. The results were explained in terms of platinum modification by the presence of niobia (SMSI effect) and tin (bimetallic effect). [Copyright &y& Elsevier]

To generalize the use of heterogeneous asymmetric catalysis we developed a new process to produce L-DOPA via cinchonine mediated Pd/C asymmetric reduction of the corresponding cinnamic acid precursor. Reaction proceeded well giving rise to good optical yield (44%). The use of O,O′-dibenzyl groups in the substrate appears to be the key to this optical purity and deserves further investigation. [Copyright &y& Elsevier]

Transalkylation of polyalkylbenzenes into monoalkylbenzenes (LABON) in the presence of benzene (B) using Lewis acids as catalysts have been studied. The effect of changes on reaction parameters such as amount, type of catalysts and feed composition mixture was considered. The transformation proceeded with good conversion using different Lewis acid catalysts [AlCl3, AlC2H5Cl2 or Al(C2H5)2Cl]. The reactions were carried out in closed systems with continuous stirring under low temperatures (300–363 K) and atmospheric pressure. [Copyright &y& Elsevier]