Abstract:

Both self-made silica and reference silica were modified by the sol-gel method and the traditional impregnation，method，and were used as carrier to prepare the chromium-based catalysts. The two silicas were investigated by using TG-DTA，BET and SEM，and the supported catalysts were used in polymerization experiments. The results showed that the reference silica had sufficiently more preliminary dry ness and better breaking strength than the self-made silica，but worse surface configuration. The activity of catalyst was enhanced by adding Ti. When the Ti modifier was added in the same amount，the catalyst which prepared with silica that had been modified by the sol-gel method had better catalytic activity compared to that catalyst which prepared with silica that had been modified by the traditional impregnation method.