Ethylene oligomerization over nickel supported silica-alumina catalysts with high selectivity for C10+ products

Abstract

The nickel (II) loading silica-alumina under various treatments in terms of aging temperature, Si/Al ratio and activation temperature were investigated by XRD, N2 adsorption-desorption, TEM, UV-Vis, NH3-TPD and XRF and then applied to catalyze the ethylene oligomerization. High aging temperature, low Si/Al ratio and high activation temperature were beneficial to high selectivity for C10+ products because of a reasonable match between Ni active sites and acid sites, high Ni loading content and less octahedral coordination Ni2+ species, respectively. Ni loading content was more important than the number of acid sites for high yield of C10+ products, and less octahedral coordination Ni2+ species favored less by-products produced at high reaction temperature. In addition, other experimental conditions, such as reaction temperature, weight hourly space velocity (WHSV) and nickel precursor were discussed in the paper.