Catalyst Coatings Applied by Plasma Spraying for the Low Pressure Polymerization of Ethylene

摘要

Silica-alumina cracking catalyst was plasma sprayed onto a metal substrate to attempt to develop a unique catalyst support form for ethylene polymerization. Seven plasma spraying parameters were optimized using a sequential analysis conducted on an accumulation of information basis. These parameters included five plasma gun operating variables and two material variables. The coating withstood the heating and cooling cycle associated with polymerization but could tolerate only 15 cycles in the thermal shock test. Temperature-time curves for various specimen thicknesses were determined. Coating adherence was achieved when the catalyst support-substrate temperature was kept below 600F. The feasibility of using the bonded support impregnated with chromium oxide as the catalyst in low pressure polymerization of ethylene was investigated. the bonded catalyst was not active and failed to produce polyethylene under the conditions studied.