Ácido acético a partir de etanol na ausência de O2 sobre catalisadores de Cu, ZnO, ZrO2 e Al2O3

Abstract

Ethanol from biomass consumption increases everyday all around the world. Besides its utilization in fuel sector, ethanol can be used as an industrial input for being a platform molecule, being able to generate drop-in chemicals. Due its growing production volume and the possibility of investing in new technologies that may promote decay in this alcohol production costs, probably in the future some processes could be replaced by others using ethanol as feedstock. One of these products is acetic acid, which is a well known chemical intermediate that has lots of relevant applications. Catalysts containing Cu, ZnO, ZrO2 and Al2O3 were studied for the reaction of acetic acid synthesis using water as an oxidation agent. Catalysts were characterized through analysis like XRF, N2 physisorption, XRD, TPR, Cu metallic surface area determination using N2O, XPS, TPD H2O and TPD ethanol. Precursors that had aurichalcite phase formed catalysts containing interacting Cu/ZnO sites which are more active in both water dissociation and acetaldehyde oxidation reactions. Meanwhile, ZrO2 and Al2O3 presence seems to make these systems less active for water dissociation. ZrO2 catalysts generate acetone as well, and due to its acid/base properties, it is possible for these systems to generate acetic acid by another reaction path which makes them as efficient as ZnO catalysts.