Low temperature one-pot synthesis of 1,1-diethoxyethane from ethanol on Bi/BiCeO_x 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/BiCeO_x for one-pot oxidative dehydrogenation-acetalization route from ethanol to DEE under 150 °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^δ+-O_v-Ce^III sites in Bi/BiCeO_x established by strong metal–support interaction, in which Bi^δ+-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.