Highly Selective Hydrogenation-Acetalization Over a Bifunctional Cu–Mn Catalyst for the Green Synthesis of DEE

Abstract

1,1-Diethoxyethane (DEE), widely used in various industries, is primarily synthesized via ethanol-acetaldehyde condensation, but acetaldehyde’s toxicity and storage issues hinder its industrial application, urgently necessitating the development of green and efficient alternative synthetic pathways. In this study, the Cu/MnO catalyst was employed for the hydrogenation-acetalization of diethyl oxalate (DEO) to synthesize DEE, not only achieving a green synthesis pathway but also addressing the issue of ethylene glycol (EG) overproduction from DEO, thereby enabling efficient resource integration and utilization. Results showed that the DEO conversion reached 100%, and the DEE selectivity reached 99%. Characterizations showed that the DEO-to-DEE reaction contains three sequential reactions, including DEO hydrogenation into EG over the Cu site, the intramolecular dehydration of EG into acetaldehyde over the MnO site, and the acetalization of acetaldehyde and ethanol over the MnO site. Particularly, the strong electronic interactions between Cu and MnO facilitate EG into DEE. This study underscores the significant potential of Cu–Mn catalysts in the selective transformation of DEO into the valuable compound, DEE.