Cooperative Catalytic Transfer for One-Pot Hydrolysis/Hydrogenation of Refined Palm Oil Using Formic Acid as a Hydrogen Source

Abstract

Significant biorefinery operations demand hydrolysis and hydrogenation reactions that require high hydrogen pressures. However, the necessity of reducing our reliance on fossil fuels for hydrogen generation drives the development of alternative hydrogen source technologies. Thus, employing hydrogen donor molecules under milder conditions is a promising approach. Herein, we present an industrially viable approach to producing saturated free fatty acids through a one-pot hydrolysis and hydrogenation reaction. In this process, formic acid (FA) acts as the hydrogen donor, while a commercial Ni/SiO 2 catalyst facilitates the hydrogenation of the fatty acid using the hydrogen generated during the decomposition of the FA. The reaction conditions were 190 °C, 20 bar of initial pressure, 750 rpm, 5:1 molar water/oil ratio, and 3 wt % Ni/SiO 2 catalyst (as a function of oil mass) using two different levels of FA. It was found that FA is a suitable catalyst for the hydrolysis reaction of palm oil, achieving a high conversion of free fatty acids. Also, an average iodine value of 19 gI 2 /100 g was obtained, and an extent of hydrogenation of 64% was achieved, indicating partial hydrogenation. The GC-FID results showed a selectivity toward hydrogenation of polyunsaturated fatty acid chains and low conversion of oleic acid. Also, we showed that qualitative and semiquantitative analyses validate the results, elucidating the conversion of triglycerides into fatty acids and providing insights into compound compositions. Infrared spectroscopy and thin-layer chromatography support these findings. Thus, such results are a promising route for saturated fatty acid production in a one-pot reaction.