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Highlights-Efficient Cu-Ni catalysts supported on activated carbon for the water gas shift reaction.-Supressed methanation activity due to the presence of Cu.-Cu-Ni alloy as a key factor of the catalytic design.-Good stability and tolerance towards start/stop situations. AbstractThe water-gas shift (WGS) reaction over structured Cu, Ni, and bimetallic Cu-Ni supported on active carbon (AC) catalysts was investigated. The structured catalysts were prepared in pellets form and applied in the medium range WGS reaction. A good activity in the 180-350 °C temperature range was registered being the bimetallic Cu-Ni:2-1/AC catalyst the best catalyst. Page 2 of 38A c c e p t e d M a n u s c r i p tThe presence of Cu mitigates the methanation activity of Ni favoring the shift process. In addition the active carbon gasification reaction was not observed for the Cu-containing catalyst converting the active carbon in a very convenient support for the WGS reaction. The stability of the bimetallic Cu-Ni:2-1/AC catalyst under continuous operation conditions, as well as its tolerance towards start/stop cycles was also evaluated.

To overcome the low equilibrium conversion in the direct synthesis of diethyl carbonate from ethanol and CO 2 under moderate reaction conditions, the reaction was conducted in a membrane reactor packed with pelletized Cu-Ni:3-1 supported on activated carbon. A SiO 2 /g-Al 2 O 3 commercial membrane and zeolite A membranes synthesized on commercial Al 2 O 3 supports were evaluated in the membrane reactor. Although characterization of the membranes by X-ray diffraction confirmed the presence of a zeolite A layer on the supports, gas permeation and permselectivity tests of ethanol and water evidenced some defects of the synthesized membranes. An increase in conversion with respect to a conventional packed-bed reactor was observed in the membrane reactors prepared on Al 2 O 3 , but equilibrium conversion was not attained. However, with the commercial membrane, the ethanol conversion was higher than the equilibrium conversion.

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The palladium on alumina (Pd@Al2O3)‐catalyzed hydrogenation of allylbenzene to propylbenzene was studied in methanol and aqueous micellar solutions of sodium dodecyl sulfate (SDS), decyltrimethylammonium bromide (DTAB), and t‐octylphenoxypolyethoxyethanol (TX‐100). Over Pd@Al2O3, propylbenzene was obtained via direct hydrogenation of allylbenzene and isomerization to β‐methylstyrene which was hydrogenated afterwards. In aqueous micellar solutions, the reaction was faster than in pure water, but slower than in methanol due to lower hydrogen solubility. In the H2O/SDS system, a higher activation energy was obtained than in methanol. For the investigated surfactants, the initial reaction rate in the micellar systems decreased in the order SDS > TX‐100 > DTAB.

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