Facet-dependent Pd0-O2−-Ce3+ active site for selective hydrogenation of linoleate ester to cis oleic acid ester

Reducing the formation of trans fatty acid in vegetable oil hydrogenation process is of significance to ensure food safety. Herein, Pd 0 -O 2− -Ce 3+ active site was constructed by strong electronic interactions between Pd 0 and CeO 2 -Polyhedrons to promote the formation of cis fatty acid. Results reveal that the abundant oxygen vacancies of CeO 2 (111) facets promote the adsorption and activation of hydrogen, leading to excellent catalytic activity of Pd/CeO 2 -Polyhedrons. Moreover, electronic reconstructed Pd 0 -O 2− -Ce 3+ active site limits the σ-bond rotation of half-hydrogenated intermediates through enhancing π backdonation and weakening the σ-bond, contributing to the reduction of trans products. Under mild conditions (30 °C, 0.3 MPa H 2 , and 2 h), Pd/CeO 2 -Polyhedrons catalyst shows exceptional methyl oleate selectivity of 52.6% with 93.8% conversion for sunflower oil hydrogenation. The catalyst has been further extended to the selective hydrogenation to several other vegetable oils such as sunflower oil, peanut oil, soybean oil, among others, under mild conditions.