In situ IR studies on ethanol transformations over CuO, CuO/ZrO2 and CuO/ZrO2/ZnO catalysts modified with NiO

Catalytic conversion of ethanol is a promising method of hydrogen production. This reaction is catalysed by metals and oxides. One of such catalysts are mixed oxides CuO/ZrO2 (Cu/Zr) with the addition of other oxides. We studied by IR spectroscopy the transformations of ethanol on Cu/Zr with addition of ZnO, NiO. Additionally, the temperature-programmed reaction of ethanol on these oxides was followed. We studied also the temperature-programmed reduction of these oxides with hydrogen. The reaction of ethanol on CuO produced acetaldehyde and water but not hydrogen, indicating, that ethanol was oxidized over this oxide. On the other hand, acetaldehyde was produced from ethanol both by oxidation and dehydrogenation over Cu/Zr (both water and hydrogen were produced). Acetaldehyde was subsequently oxidized to acetic acid, which was next transformed to acetone. The addition of ZnO facilitated the formation of ace- tone evidencing that ZnO is effective catalyst for the reaction acetic acid -> acetone. The addition of NiO caused the decomposition of acetaldehyde to methane and CO. (C) 2022 Elsevier B.V. All rights reserved.

Automated summary

Catalytic conversion of ethanol into hydrogen is a promising method. This study focused on the transformations of ethanol on CuO/ZrO2 (Cu/Zr) mixed oxides with the addition of ZnO and NiO. It was found that CuO oxidized ethanol into acetaldehyde and water, while Cu/Zr performed both oxidation and dehydrogenation of ethanol, producing acetaldehyde, water, and hydrogen. ZnO facilitated the formation of acetone, and NiO caused the decomposition of acetaldehyde into methane and CO.