提高非贵金属临氢脱腊催化剂异构化能力的研究

The optimum parameters as well as the ZSM-8 molecular sieve product with good properties were obtained through detailed synthesis investigation under hydrothermal conditions. Composite support, which was formed from an Amorphous Si-Al gel and ZSM-8 zeolite, was impregnated with active components to produce the non-precious metal catalyst for hydrodewaxing. The aim to increase the catalytic isomerization ability was thus realized by additional introduction of zinc and tungsten beside the main molybdenum and nickel. It has been shown that the catalytic properties are significantly influenced by both the catalyst support and the addition of the promoters. However, the addition sequence of zinc shows little effect. Compared to the β-zeolite based catalyst, the new ZSM-8 based catalyst showed a better catalytic behavior, which was characterized by an increased yield and a higher viscosity index of lube base oil product. The improvement of catalyst performance could be ascribed to the increased isomerization ability of new catalyst system.