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Abstract: The influence of different additives to V2O5/TiO2 catalyst for the gas phase partial oxidation of toluene was investigated in a microchannel reactor, where well-controlled reaction conditions were provided without heat and mass transfer influence. It was found that K-doping decreased the catalyst selectivity for benzaldehyde and benzoic acid. The addition of Sb promoted the selectivity but inhibited the catalyst activity greatly. The modification with Ag remarkably improved the catalyst performance in terms of increasing benzaldehyde and benzoic acid selectivity along with an increased activity. With Ag modified V2O5/TiO2 as catalyst and pure oxygen as oxidant, the total selectivity of benzaldehyde and benzoic acid reached over 80% with the toluene conversion above 10%. The maximum space–time yield of 4.82kgh−1 L−1 has been achieved, calculated on the basis of the channel volume. [Copyright &y& Elsevier]

Highlights: [•] Process of CO2 absorption by MEA solutions was analyzed in microchannel reactors. [•] Effects of relevant parameters on the process were evaluated. [•] k 1 for CO2 reaction with MEA was successfully determined under ambient pressure. [•] An Arrhenius-type equation was obtained for k 1 for CO2 absorption in microchannel. [Copyright &y& Elsevier]

Abstract: This study showed that a ZnO–Cr2O3/CeO2–ZrO2/Al2O3 (Zn–Cr) catalyst was a promising catalyst for hydrogen production from methanol due to its high stability and selectivity. There was no significant deactivation of the catalyst over 300min of continuous operation when water was introduced into the feed. In the absence of water, the catalyst deactivated rapidly due to coke formation. The addition of water into the feed changed the route of methanol conversion and improved its rate. In order to investigate the pathway of CO formation, three reactions, i.e. decomposition of methanol (DM), steam reforming of methanol (SRM) and water gas-shift (WGS), were studied in this paper. The results showed that CO and CO2 were produced through the DM reaction and SRM reaction, respectively. The WGS and reverse WGS reactions were negligible. Adding H2 and CO in the feed did not influence the process behavior of the SRM reaction. The addition of CO2 and H2O into the feed decreased the yield of CO2. [Copyright &y& Elsevier]

Abstract: A mathematic model of H2S catalytic oxidation on impregnated activated carbon with fouling of catalyst has been developed. Kinetic studies were carried out in a fixed activated carbon bed under atmospheric pressure and low temperature (30–80°C). The effects of flow rate, H2S inlet concentration, temperature and relativity humidity were analyzed. Experimental results of breakthrough curves were used to obtain kinetic parameters accounted for axial dispersion, external and internal mass-transfer resistances as well as effects of S deposition on inner-face of the catalyst. The model described satisfactorily the experimental breakthrough curves and well explained the performance of oxidation. The exothermic heat of adsorption and activation energy assuming Arrhenius type of temperature dependence of the equilibrium constant was determined to be 44.6 and 29.9kJ/mol, respectively. ɛ p0, α and β were used to quantify the behavior of H2S oxidation at different operating conditions. The effect of relative humidity on ɛ p0, α and β is significant in the relative humidity range under study. The mathematic model can be considered as a reliable tool for process design and scale-up of similar system. [Copyright &y& Elsevier]