Fabrication of dual-activated coal gangue-loaded nickel-based catalyst for dioctyl phthalate hydrogenation

The development of high-performance and low-cost catalysts is of great significance in the field of catalytic hydrogenation. It is advisable to convert the reserved coal gangue waste into new materials with special functions. Therefore, in this work, dual-activated coal gangue was used as support to prepare Ni-based catalysts that could catalyze the hydrogenation of dioctyl phthalate to synthesize di(2-ethylhexyl) hexahydro-phthalate. The conversion of dioctyl phthalate can reach 99.9 % over the Ni/ZMC-1 catalyst using dual-activated coal gangue as support. This catalyst can be recycled 8 times without obvious loss of its initial activity. Characterization and experimental results revealed that both activation treatments have significant impact on surface structure and composition of catalysts. Thermal activation could remove toxic elements such as S and produce a larger specific surface area, while chemical activation could enhance the dispersion of the active metal and the metal-support interaction, which ultimately improved the activity and stability of the catalyst, simultaneously. This strategy provides a good reference for the high-value utilization of coal gangue and the design of excellent catalyst.