Synthesis and Characterization of Phillips Cr/SiO2 Catalyst and Ethylene polymerization

The Cr/SiO2 system is one of the simplest examples of a catalyst where the sites are formed by anchoring a well-known chromium compound to the hydroxyl groups of the silica surface. By characterization of the catalysts, investigation of the polymerization behavior and the microstructures of polymers, several vital factors such as cocatalyst, calcination temperature, total chromium loading, polymerization temperature, pressure and hydrogen were systematically investigated. The suitable calcination temperature and total chromium loading were ≤600°C and ≤0.5 wt%, respectively. The chromium compounds or complex ions have been deposited by ion exchange, by impregnation, and by adsorption. In this work, we described characterization the stages of catalyst synthesis and used it for ethylene polymerization. The synthesis of catalyst includestree stage, preparation of support, loading chromium and activation catalyst. The synthesis of support stage is more important in Cr/SiO2 synthesis. The identity of catalyst was done by FT-IR spectroscopy and polyethylene properties obtained through XRD, SEM, DSC analyses

Keywords:

Chromium , Ethylene polymerization , Phillips catalyst , HDPE , MWD , Activity , Aerogel