Study on the catalytic performance and kinetics of ethylene oligomerization catalyzed by Salicylaldiminato Phthalocyanine nickel catalyst

Abstract

A novel salicylaldiminato phthalocyanine nickel catalyst was prepared and characterized by FT-IR, UV–Vis, ¹H NMR, ICP-MS, TG-DSC and elemental analysis. The catalytic performance of ethylene oligomerization catalyzed by salicylaldiminato phthalocyanine nickel catalyst was investigated. The catalytic activity could reach up to 1.25 × 10⁶ g (mol Ni·h)⁻¹, and the products were mainly butene, hexene as well as a small amount of octene when the cyclohexane was used as solvent, the MAO was used as co-catalyst. In addition, the kinetics of ethylene oligomerization was also investigated. The kinetic parameters such as the reaction order to the nickel molar concentration (n) and oligomerization pressure (m), the apparent activation energy (Ea) and the pre-exponential factor (A) were determined. The result indicated that the reaction order to the nickel molar concentration was 1.18, the reaction order to oligomerization pressure was 1.12, and the apparent activation energy was 54.78 kJ/mol when the nickel concentration was 5 μmol/L, the oligomerization pressure was 1.0 MPa, and the oligomerization temperature was 5–35 °C.