One of the major goals of current research on energy conversion is the mitigation of CO 2 emission. A beneficial scenario for CO 2 utilization is the catalytic conversion of industrial waste or process gases into valuable products. Within the crossindustry approach of Carbon2Chem the synthesis of methanol from steel mill exhaust gases is a promising way to close the carbon cycle based on additional sustainably produced H 2 . New catalyst requirements have to be met due to fluctuating feed gas composition and availability as well as gas separation and purification issues.

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High surface area ZnO nanoparticles are synthesized by applying a novel continuous precipitation method using a micromixer coupled directly to a bench-top spray dryer. The polycrystalline material is obtained by fast turbulent precipitation from aqueous zinc nitrate solutions with either sodium or potassium carbonate followed by immediate quenching of the aging due to the rapid water removal. Specific surface areas up to 98 m2 g-1 are obtained, depending on the precipitant and the sequence of unit operations applied after precipitation

A novel continuous method for the preparation of a ternary Cu/ZnO/Al 2 O 3 catalyst based on a cascade of micromixers and a tubular aging reactor is presented as a promising alternative route to the conventional batch process. Its application, in combination with immediate spray drying, enables monitoring of the formation of the final precursor by exchange reactions between initially separated phases during the aging step.These exchange reactions were successfully simulated by consecutive precipitation by using micromixers in series as analytical tool. After 60 min of continuous aging, calcination, and reduction, a catalyst is produced that exhibits an almost equal mass-related activity in methanol synthesis compared to a commercial catalyst and an area-related activity that is about 50 % higher.[a] Dr.

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This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.Today, the use of renewable energies and recycling of climate-changing gases are increasingly important. In this context, coupling of methanation with small, decentralized CO 2 sources such as biogas plants provides one possibility. However, fluctuating availability of renewables for hydrogen production in combination with small storage volumes result in an enhanced demand for dynamic process operation. This leads to new research challenges with respect to the required catalysts and the overall process design. To draw reliable conclusions about the catalytic performance under dynamic process operation, the mechanism of the methanation reaction as well as typical deactivation procedures of the catalyst applied under steady-state conditions have to be reviewed thoroughly.

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The selective oxidation of aqueous ethanol solutions with air over two commercial 1.5 and 1 wt% Au/TiO2 catalysts was investigated in six stirred mini-autoclaves operated in parallel. The catalysts were characterised by various techniques including elemental analysis, N2 physisorption, X-ray diffraction and transmission electron microscopy (TEM). Temperature, pressure, ethanol concentration, catalyst concentration and reaction time were varied in the batch experiments to study the reaction kinetics. It was possible to confirm the generally accepted mechanism of primary alcohol oxidation, in which acetaldehyde is a primary product of the oxidation that quickly undergoes further transformation to acetic acid. In presence of both acetic acid and ethanol the formation of ethyl acetate takes place until equilibrium conditions are reached. The high yields of acetic acid can be rationalised by the inhibited total oxidation of acetic acid under the applied reaction conditions. Improper storage of the gold catalysts in air exposed to light was found to lead to an irreversible change of the performance, which cannot be restored by means of recalcination. Sintering and blocking of surface sites by deposits were ruled out as possible causes for the deactivation