Selective production of alkanes and fatty alcohol via hydrodeoxygenation of palmitic acid over red mud-supported nickel catalysts

Abstract

Production of valuable chemicals and fuels from waste animal fat and vegetable oils can serve as alternatives to fossil energy. In this study, the selective production of alkanes and higher fatty alcohol via hydrodeoxygenation (HDO) of palmitic acid over red mud-supported nickel catalysts (Ni/RM) was reported. Meanwhile, the study has investigated the effect of Ni loading, reaction temperature, hydrogen pressure on the HDO of palmitic acid, analyzed the reusability of Ni/RM and explored the possible reaction mechanism. The results show that palmitic acid is completely converted over 7%Ni/RM. The selectivity of fatty alcohol and alkanes are 92.54% (260 °C) and 100% (300 °C), respectively. Ni/RM has shown the highest catalytic performance as compared to commercial Ni/SiO2 and Ni/γ-Al2O3 catalysts. The 7%Ni/RM also demonstrates stable catalytic performance after multiple times of reuse. Moreover, hexadecanol plays an important role in hydrodeoxygenation, decarbonylation, and decarboxylation routes.