Hydrogenation of Dodecanoic Acid over Iridium-Based Catalysts

This study develops iridium (Ir)-based catalysts for the hydrogenation of dodecanoic acid, a medium-chain fatty acid abundant in palm kernel and coconut oils, for producing fatty alcohols and alkanes. Among various supports such as AlOOH, SiO2, TiO2, Nb2O5, MoO3, Ta2O5, ZrO2, and WO3 for 7.5 wt% Ir loading, an Ir-impregnated Nb2O5 (Ir/Nb2O5) catalyst demonstrated remarkable performance with 100% conversion and a high dodecanol yield (89.1%) under mild conditions (170 °C, 4.0 MPa H2), while at higher temperatures and pressures (200 °C, 8.0 MPa H2), Ir-impregnated MoO3 (Ir/MoO3) produced dodecane as the main product with a yield of 90.7%. These findings can tailor product selectivity toward desired bio-based chemicals and fuels, offering sustainable pathways for fatty acid hydrogenation by optimizing catalyst supports and reaction conditions in the Ir-based catalyst.