摘要
氯乙烯是土壤和地下水中存在的污染物 ,其去除的有效途径之一为微生物降解 .本研究在温度 2 0℃、氯乙烯初始浓度 1 0 0 μmol/L条件下 ,对不同氧化还原条件下四氯乙烯、cis 二氯乙烯及一氯乙烯的微生物降解进行了实验 .结果表明 ,在铁还原和碳酸氢盐存在条件下 ,四氯乙烯以 0 2 6/d和 0 31 /d的速率分别脱氯为三氯乙烯和cis 二氯乙烯 .在脂肪酸存在条件下 ,四氯乙烯、cis 二氯乙烯和一氯乙烯均完全脱氯为乙烯 ,但后两者脱氯速率( 0 0 4 /d)明显低于前者 ( 0 5 7/d) .在反硝化、锰还原及硫还原条件下 ,不同取代氯乙烯降解均不明显 .当环境温度降至 1 2℃ ,脱氯菌活性降低 。
Chlorinated ethenes are pollutants in contaminated soil and groundwater, and one of the efficient way to remove them is biodegradation. In this paper, the microbial breakdown of PCE, cis DCE and VC with initial concentrations of 100 μmol/L were studied under different redox conditions at temperature 20℃. The results showed that in the presence of ferric iron and carbon dioxide, PCE were dechlorinated to TCE (0 26/day) and cis DCE (0 31/day), respectively. In the presence of fatty acids and without competition from inorganic electron acceptors, all the studied chlorinated compounds were completely dechlorinated to ethenes. However, the degradation rates of cis DCE and VC (0 04/day) were much lower than that of PCE (0 57/day). Under denitrifying, manganese reducing and sulfate reducing conditions, no degradation of chloroethenes was observed. When the temperature was lowered to 12℃,the activities of dechlorinating microbes were also reduced, nevertheless, the completely reductive dechlorination of chloroethenes still occurred.
出处
《环境科学》
EI
CAS
CSCD
北大核心
2002年第2期29-33,共5页
Environmental Science
基金
国家重点基础研究专项经费资助项目(G19990 45 711)
国家自然科学基金资助项目(49972 0 82 )
中国博士后基金项目 (2 0 0 0 )
回国留学人员启动基金项目 (2 0 0 1)
关键词
氯乙烯
微生物降解
氧化还原
脱氯
chloroethenes
biodegradation
redox
dechlorination
