Oleic acid decarboxylation to produce C8-C17 alkanes catalyzed by Pt and Ni on a MOF-derived zirconia

UiO-66 specimens having different acetic acid/ZrCl 4 molar ratios were prepared and pyrolyzed to ZrO 2 as supports for Pt and Ni, intended to catalyze the decarboxylation of oleic acid. Brunauer-Emmett-Teller surface area analyses, NH 3 temperature-programmed desorption and pyridine adsorption infrared spectroscopy showed that the material made using an acetic acid/ZrCl 4 molar ratio of 100 (ZrO 2 -100) had the largest specific surface area, acid amount and acid strength values. The yield of C 8 -C 17 alkanes obtained from Ni/ZrO 2 -100 exceeded that provided by Pt/ZrO 2 -100 because the latter possessed more acidic sites than the former, which excessively cracked long-chain hydrocarbons. The 1 wt% Ni/ZrO 2 -100 catalyst showed the best catalytic performance, with 96.4% conversion of oleic acid and an 80.6% yield of C 8 -C 17 alkanes after 4 h at 340 °C under a CO 2 atmosphere at a pressure of 18 bar. The conversion of oleic acid remained almost unchanged after 4 reuses of this catalyst whereas the yield of C 8 -C 17 alkanes decreased to 66.7%. This result is attributed to a loss of acidic sites and an increase in carbon build-up.