Study on SiO2/γ-Al2O3 catalyst chloridized by Cl2

A new type of catalyst using the polymerization of alpha-olefin to produce lubricating base oil was studied. Under the protection of N-2 , the mixture of SiO2/gamma-Al2O3 was chloridized by Cl-2 . The effects of SiO2/gamma-Al2O3 molar ratio, N 2 /Cl 2 volumetric ratio, chloridizing temperature, and chloridizing time on the performance of catalysts were researched. The kinetic viscosity is used as the evaluated standard. The results show that the catalysts chloridized by Cl-2 possess as high activity as AlCl3 for polymerization of alpha-olefin with mild reactivity and weak corrosion. The optimal conditions were: SiO2/gamma-Al O-2(3) molar ratio 1, N-2/Cl-2 volumetric ratio 0.2, chloridizing temperature 500 degrees C, and chloridizing time > 4 h. By adding SiO2 , this catalyst has not only kept AlCl3's unusually high activation to olefin-polymerization, but also overcome the deficiency of a strong caustic and the too violent response of AlCl3 . Through comparison with important evaluations, such as bromine number and kinetic viscosity, this catalyst is obviously better than those Al2O3/SiO2 catalysts reported in former documents.