Preparation and properties of nickel preimpregnated CYCTS supports for hydrotreating coker gas oil

The citric treated Y zeolite composite titania–silica (CYCTS) supports and nickel (Ni) preimpregnated CYCTS supports (NiCm, m is the Ni content by weight) were prepared by sol–gel combined with CO2 supercritical drying method. Effects of the Ni concentration on the structure, physical and chemical properties were examined using BET, H2-TPR, XRD, and UV–vis DRS. Hydrotreating catalysts were prepared with CYCTS or NiCm as supports and Ni–tungsten (W) as metal components. The hydrotreating performances of the catalysts were examined with Liaohe coker gas oil (CGO) as feedstock. The results indicated that the Ni preimpregnated supports had suitable mesoporous structure and surface area, and the TiO2 particles size become smaller. At the same time, the Ni preimpregnation method could promote the formation of highly active nickel species in octahedral sites and improved the dispersivity of WO3. The hydrotreating performances of the Ni–W catalysts using the NiCm supports for Liaohe CGO had been remarkably promoted, especially the hydrodenitrogenation (HDN) performance.