epsilon-Caprolactam-degradation by Alcaligenes faecalis for bioremediation of wastewater of a nylon-6 production plant

摘要

Alcaligenes faecalis G utilized 95-97% of 5-15 g epsilon-caprolactam l(-1) in 24-48 h over a pH range of 6-8.5 and at 23-40 degreesC, without complex nutrient requirement. In the absence of KH2PO4 and K2HPO4/MgSO4 in the medium, only 7.6% and 0.2% of 10 g caprolactam l(-1) was utilized, respectively. The chemical oxygen demand (COD) of the wastewater of nylon-6 plant was mainly due to its caprolactam content. A. faecalis G decreased the caprolactam content and COD of the wastewater by 80-90% of the original in spite of the wastewater having higher caprolactam content (3600 mg l(-1)) and COD (7700 mg l(-1)) than those of any of the previous reports.