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Phillips catalyst
Ethylene polymerization catalyst / From Wikipedia, the free encyclopedia
The Phillips catalyst, or the Phillips supported chromium catalyst, is the catalyst used to produce approximately half of the world's polyethylene. A heterogeneous catalyst, it consists of a chromium oxide supported on silica gel.[1] Polyethylene, the most-produced synthetic polymer, is produced industrially by the polymerization of ethylene:
- n C2H4 → (C2H4)n
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Although exergonic (i.e., thermodynamically favorable), the reaction requires catalysts. Three main catalysts are employed commercially: the Phillips catalyst, Ziegler–Natta catalysts (based on titanium trichloride), and, for specialty polymers, metallocene-based catalysts.