Low temperature one-pot synthesis of 1,1-diethoxyethane from ethanol on Bi/BiCeOx with strong metal-support interactions

The direct conversion of ethanol to 1,1-diethoxyethane (DEE) through one-pot dehydrogenation-acetalization has attracted broad interest from both academia and industry. Based on thermodynamics, the oxidative dehydrogenation of alcohol to acetaldehyde requires high temperature to activate oxygen to realize the C-H cleavage, while the acetalization of acetaldehyde with ethanol is exothermic reversible reaction favorable at low temperature. The mismatching of the reaction condition for the two consecutive steps makes it a great challenge to achieve both high ethanol conversion and high DEE selectivity. This work reports a highly efficient bi-functional catalysis by Bi/BiCeOx for one-pot oxidative dehydrogenation-acetalization route from ethanol to DEE under 150 degrees C and ambient pressure, affording a selectivity of 98.5% +/- 0.5% to DEE at an ethanol conversion of 87.0% +/- 1.0%. An efficient tandem catalysis has been achieved on the interfacial Bi delta+-O-v-Ce-III sites in Bi/BiCeOx established by strong metal-support interaction, in which Bi delta+-O-v- sites contribute to the oxidative dehydrogenation of ethanol at mild temperature, and -O-v-Ce-III sites to the subsequent acetalization between the generated acetaldehyde and ethanol.