Conversion of Ethanol to Ethyl Acetate Using Gold-based Bifunctional Catalysts

Abstract

Ethyl acetate is widely used as a replacement for aromatic solvents in paints, inks and dyes; moreover, it can be used in the pharmaceutical, cosmetic, and food industry. In countries with high bioethanol production, such as Brazil, there is an increasing commercial and environmental interest in the synthesis of ethyl acetate from bioethanol. The two most studies reaction routes for this reaction are: i) aerobic oxidation of ethanol to acetic acid followed by esterification, and 2) dehydrogenation of ethanol to acetaldehyde in inert atmosphere followed by a coupling between the aldehyde and ethanol. While copper and palladium based catalysts are largely studies for this reaction, few reports can be found for gold catalysts. Au is a potential catalyst for the conversion of ethanol to ethyl acetate once it is highly selective for the oxidation of ethanol to acetic acid and for the dehydrogenation of ethanol to acetaldehyde. Therefore, in this research proposal we intend to prepare bifunctional catalysts based on gold supported in solid acids for the production of ethyl acetate from ethanol in the presence and absence of oxygen. The most promising catalysts will be used for kinetic and thermodynamics studies in order to obtain the reaction orders for reactants and products, turnover frequencies, and activation energy for each of the reaction steps. The stability of the catalysts will also be quantitatively studied by determining the deactivation rate constant.