Oxalic acid-mediated catalytic transfer hydrodeoxygenation of waste cooking oil

Abstract Oxalic acid was employed for the catalytic transfer hydrogenation of used vegetable cooking oil. Hydrogen production was achieved upon the decomposition of oxalic acid using a commercial industrially sulfided NiW/SiO2-Al2O3 catalyst. Products were analysed by attenuated infrared spectroscopy, simulated distillation and gas chromatography-flame ionisation detection/thermal conductivity detection for the produced gases. No hydrogen gas was added for these tests, which were performed in a nitrogen atmosphere at an initial pressure of 0 bar in an autoclave. Unprecedented results were obtained, with a high yield of deoxygenated hydrotreated vegetable oil hydrocarbons being achieved while avoiding the use of formic acid, which is both toxic and irritant.