Biodegradation of quinoline in crude oil

Removal of quinoline, which is typical of nitrogen-containing compounds in crude oil, was achieved by a biodegradation reaction by Comamonas sp TKV3-2 -1. The aerobic strain, Comamonas sp TKV3-2-1, which can grow utilizing qui noline as the sources of both carbon and nitrogen, degraded quinoline to 2- hydroxyquinoline, finally to water-soluble substances. The degradation reac tion of 2-hydroxyquinoline was revealed to be regarded as a rate-limiting s tep controlling the overall reaction of biodenitrogenation process of quino line in crude oil. The degradation rate of 2-hydroxyquinoline in a stirred fermenter had a maximum of 211 mg 2-hydroxyquinoline g-cell-lh-l when the p ortion of crude oil in the reaction mixture, the cell concentration and the rotational speed of agitation impeller were 83.3%(v/v), 28.5 gdm(-3) and 1 1.7 s(-1), respectively. After the reaction was completed, the crude oil an d the cell suspension could be separated efficiently by centrifuging. The p ossibility of constructing a bioprocess for removing quinoline in crude oil under storage is also discussed. (C) 2001 Society of Chemical Industry.