Synthesis of C3+ alcohols through ethanol condensation and carbon-carbon coupling of ethanol with CO2

Abstract

C3+ alcohols are widely used as organic solvents, raw chemicals and fuel additives. However, the self-condensation of alcohol can limit the distribution of products. Herein, the binary metal oxide ZnO-ZrO2 with solid solution structure was prepared and applied into the synthesis of higher alcohols through the ethanol condensation and the coupling of ethanol with the CO2 hydrogenation. The optimized 0.3ZnO-ZrO2 solid-solution catalyst shows that ethanol conversion can reach 29% with the C3+ alcohols (1-propanol, 1-butanol and 1-hexanol) selectivity of 67%. The high selectivity of C3+ alcohols can be attributed to the acid-base bifunction for performing the condensation of ethanol and the coupling of ethanol and the CHxO intermediates that are produced through CO2 hydrogenation. This work opens a new avenue for the synthesis of C3+ alcohols.