Short contact time thermal cracking of carbonaceous wastes to alpha olefins

A continuous short contact time thermal cracker was constructed and operate d to investigate the production of alpha olefins in the C-9-C-16 range. Alp ha olefins in this range are normally used as chemical feedstocks for lubri cants, surfactants, alcohols and other valuable commodities. The CETC unit was operated at 100 g h(-1) between 495 and 570 degrees C using paraffin wa x, waste wax from a gold refinery, waste plastic-derived oil and topped was te plastic-derived (wax enriched) oil. The effect of operating temperature, heavy ends recycle rate and feed types on the production of alpha olefins was examined in detail. It was found that the concentration of heavy paraff ins with carbon numbers greater than C-16 in the heavy ends recycle stream is a good indicator for estimating the concentration of alpha olefins in th e C-9-C-16 range. It was shown that feed type is the most critical factor i n determining high alpha olefins yield in this range. Following is the orde r of suitability for producing alpha olefins in the C-9-C-16 range: paraffi n wax > plastic-derived oil (topped) > plastic-derived oil (as received),wa ste wax. (C) 1999 Elsevier Science B.V. All rights reserved.