Metal-acid dual sites in Pd/SiO2-Al2O3 synergistically catalyze selective hydrogenation-etherification of furfural to bioether.

An effective bifunctional Pd/SiO 2 -Al 2 O 3 -30 catalyst was synthesized for the selective hydrogenation-etherification of furfural to furfuryl ether and exhibited 86.2% 2-(isopropoxymethyl)furan yield with the synergistic catalysis of Pd particles and Brønsted–Lewis acid sites. [Display omitted] • An effective bifunctional Pd/SiO 2 -Al 2 O 3 -30 catalyst was synthesized successfully. • The catalyst exhibited 86.2% 2-(isopropoxymethyl)furan yield. • The incorporation of Si suppressed the furan ring hydrogenation. • The formation of Brønsted acid centers catalyzed the etherification step. • A Pd-Brønsted-Lewis acid synergistic catalysis mechanism was proposed. Production of ethers from biomass-derived platform compounds is a substantial scientific challenge and industrial pursuit. In this study, an effective bifunctional Pd/SiO 2 -Al 2 O 3 -30 catalyst was synthesized for the selective hydrogenation-etherification of furfural (FAL) to furfuryl ether and exhibited an 86.2% 2-(isopropoxymethyl)furan yield with the synergistic catalysis of Pd particles and Brønsted–Lewis acid sites. The incorporation of Si with Al 2 O 3 in the catalysts weakened the metal-support interaction and resulted in larger Pd particles, which inhibited the hydrogenation of the furan ring. Meanwhile, the formation of Brønsted acid centers catalyzed the etherification step and promoted the selectivity to corresponding ethers. Furthermore, extensive reaction results and characterizations uncovered the metal-acid synergistic catalysis mechanism for the selective hydrogenation-etherification of FAL. This work provides an innovative strategy for preparing effective metal-acid bifunctional catalysts for the hydrogenation-etherification of bio-aldehydes to ethers. [ABSTRACT FROM AUTHOR]