Hydroconversion of methyl laurate over beta-zeolite-supported Ni–Mo catalysts: Effect of acid and base treatments of beta zeolite

Beta-zeolite-supported Ni–Mo catalysts, NiMo/HBeta, were developed and applied to the hydroconversion of methyl laurate under a hydrogen pressure of 0.4 MPa. Compared with the Ni–Mo catalyst supported on a zeolite with no Al content, NiMo/HBeta exhibited high catalytic activity and selectivity for n-dodecane produced through the hydrodeoxygenation (HDO) process. Furthermore, prior to Ni–Mo particle loading, beta zeolite was acid-treated with HNO₃ solution or base-treated with tetraethylammonium hydroxide (TEAOH) or NaOH solutions. The acid and base treatments influenced the Ni–Mo particles, with large Ni–Mo particles formed on the acid-treated beta zeolite and small, highly dispersed Ni–Mo particles formed on the base-treated beta zeolites. Both the acid- and TEAOH-treated beta zeolites improved the catalytic activity and enhanced the HDO process, whereas the NaOH-treated beta zeolite slightly depressed the catalytic activity. An increased ratio of Brønsted acid sites in beta zeolite played an important role in improving both the catalytic activity and the HDO process. The combination of the TEAOH treatment of beta zeolite with subsequent acid treatment was effective for further improving the catalytic activity while maintaining high n-dodecane selectivity.