文献类型： 外文期刊

作者： Ba, Yu-Xin ¹ ; Hu, Zheng-Yi ¹ ; Bao, Peng ¹ ; Qiao, Min ² ; Hua, Jing ¹ ; Wu, Chun-Yan ³ ; Wu, Jian-Zhi ² ;

作者机构： 1.Chinese Acad Sci, Coll Resources & Environm, Grad Univ, Beijing 100049, Peoples R China

2.Chinese Acad Sci, Res Ctr Ecoenvironm Sci, Beijing 100085, Peoples R China

3.Zhejiang Acad Agr Sci, Inst Environm Resources & Soil Fertilizer, Hangzhou 310021, Zhejiang, Peoples R China

关键词： Abiotic dechlorination;Ferrous iron;Organochlorine;Sulfide

期刊名称：JOURNAL OF SOILS AND SEDIMENTS （ 影响因子：3.308； 五年影响因子：3.586 ）

ISSN： 1439-0108

年卷期： 2011 年 11 卷 7 期

页码：

收录情况： SCI

摘要： Abiotic dechlorination of organochlorine pollutants seems to occur more efficiently in nature than previously thought. Ferrous (Fe(2+)) and sulfide (S(2-)) ions have been shown to be effective dechlorinating reagents. However, little is known about the interactions between Fe(2+) and S(2-) during dechlorination of 1,1,1-trichoro-2,2-bis(p-chlorophenyl)-ethane (DDT) in soil, in spite of the fact that these ions co-exist in waterlogged soils. An anaerobic soil incubation experiment was run for 192 h to investigate S(2-) (1.0, 10 mM)-induced abiotic dechlorination of p,p'-DDT in waterlogged soil (soil/water = 1/20). In addition, the influence of Fe(2+) (3.0 mM) on S(2-) (0.5, 5.0 mM)-induced abiotic dechlorination of p,p'-DDT (2 mu g ml(-1)) was evaluated in soil solution and in distilled deionized water to identify the dechlorination mechanism under anaerobic incubation conditions for 6 h due to the complexity of soil, based on the determination of residual p,p'-DDT in media by gas chromatograph (GC)-ECD and the identification of metabolites of p,p'-DDT by GC-MSD. S(2-)-induced dechlorination of p,p'-DDT exhibited rapid and slow phases in three media (waterlogged soil, soil solution, and distilled deionized water). The addition of Fe(2+) significantly accelerated S(2-)-induced dechlorination, reduced the remaining concentrations of p,p'-DDT at the turning point and the end point for the dechlorination reaction, and shortened the time to reach equilibrium in two aqueous media. In all, 93% and 48% of p,p'-DDT was dechlorinated in soils supplied with 1.0 and 10 mM S (,) (2-) respectively. The underlying mechanism can be attributed to the coupling effect of Fe(2+) and S(2-) on dechlorination of DDT since the rates of dechlorination of p,p'-DDT treated by 0.5 and 5.0 mM S(2-) over 6 h were significantly greater with Fe(2+) addition than without Fe(2+) addition in aqueous phase media. The metabolites of p,p'-DDT found in the three media were identified as p,p'-DDD, p,p'-DDE, and p,p'-DDMU, with or without the addition of Fe(2+). Combined Fe(2+)/S(2-)-induced dechlorination of DDT could be important for in situ remediation of DDT-contaminated soil/sediment given that Fe(2+) and S(2-) often co-exist in anaerobic conditions.