Formation of polychlorinated diphenyl ethers from condensation of chlorophenols with chlorobenzenes
文献类型：期刊论文
| 作者 | Liu, Wenxia ; Zheng, Minghui ; Liu, Wenbin ; Ma, Xiaodong ; Qian, Yong ; Zhang, Bing |
| 刊名 | ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
 |
| 出版日期 | 2008-01 |
| 卷号 | 15期号:1页码:84-88 |
| 关键词 | condensation pentachlorophenol polychlorinated dibenzofurans polychlorinated dibenzo-p-dioxins polychlorinated diphenyl ethers polychlorobenzenes |
| 英文摘要 | Background and Aims. Polychlorinated diphenyl ethers (PCDEs), which are among the members of persistent organic pollutants, and PCDEs have been determined in a number of environmental samples. The main possible sources are the technical production of chlorinated phenols and all processes of incomplete combustion. PCDEs were observed in the fly ash from a municipal waste incinerator (MWI). It was speculated that the condensation of chlorophenols with chlorobenzenes occurred via PCDEs to form polychlorinated dibenzofurans (PCDFs). Nevertheless, PCDEs formation from condensation of chlorophenols with chlorobenzenes has not been confirmed by experimental observation. The objective of this paper is to investigate the formation mechanism of PCDEs from the condensation of chlorophenols with chlorobenzenes. The results are expected to be helpful in understanding the formation of PCDEs and in controlling and abating PCDEs emissions from MWL. Methods. The pyrolysis of pentachlorophenol (PCP) and/or polychlorobenzenes (PCBz) was carried out in a sealed glass tube. The reaction products were extracted and purified with K2CO3 solution. The samples were concentrated and then cleaned up on an alumina column. GC/MS was used for identification and quantification of reaction products. Results and Discussion. The results showed that the pyrolysis of hexachloro benzene (HCB) at 340 degrees C for 6 h led to the formation of decachlorodiphenyl ether (DCDE) (2.41 mu g/mg) and octachlorodibenzo-p-dioxins (OCDD) (0.24 mu g/mg), while the pyrolysis of PCP yielded DCDE (13.08 mu g/mg) and OCDD (180.13 mu g/mg). In addition, the amount of DCDE formation from the pyrolysis of the mixture of PCP and HCB was 4.65 times higher than the total amount of DCDE formation from the pyrolysis of HCB and PCP, respectively. This indicated that PCP and HCB were prone to condensation and formation of DCDE. DCDE was the main congener of PCDEs from condensation of PCP with HCB at 340,400 and 450 degrees C. A small amount of nonachlorodiphenyl ether (NCDE) was formed by dechlorination reaction at 450 degrees C. The condensation of PCP with 1,2,4,5-tetrachloro benzene (Cl(4)Bz) formed 2,2',3,4,4',5,5',6-octa-chlorodiphenyl ether (OCDE). Small amounts of heptachlorodiphenyl ether (HpCDE) and hexachlorodiphenyl ether (HxCDE) were detected at 450 degrees C. Meanwhile, polychlorinated dibenzo-p-dioxins (PCDDs) and PCDFs were detected from the condensation of PCP and PCBz. Conclusions. Experimental studies clarified the behavior of the formation of PCDEs from condensation of polychlorophenols and PCBz. The condensation of polychlorophenols with PCBz formed PCDEs through elimination of HCl between polychlorophenols and PCBz molecules. Another pathway of PCDEs formation was elimination of H2O between two polychlorophenol molecules. In addition, dechlorination processes had caused the specific homologous pattern of PCDEs under higher temperatures. |
| WOS记录号 | WOS:000253493200014 |
| 源URL | [http://ir.rcees.ac.cn/handle/311016/21951]  |
| 专题 | 生态环境研究中心_环境化学与生态毒理学国家重点实验室 |
| 推荐引用方式 GB/T 7714 | Liu, Wenxia,Zheng, Minghui,Liu, Wenbin,et al. Formation of polychlorinated diphenyl ethers from condensation of chlorophenols with chlorobenzenes[J]. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH,2008,15(1):84-88. |
| APA | Liu, Wenxia,Zheng, Minghui,Liu, Wenbin,Ma, Xiaodong,Qian, Yong,&Zhang, Bing.(2008).Formation of polychlorinated diphenyl ethers from condensation of chlorophenols with chlorobenzenes.ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH,15(1),84-88. |
| MLA | Liu, Wenxia,et al."Formation of polychlorinated diphenyl ethers from condensation of chlorophenols with chlorobenzenes".ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH 15.1(2008):84-88. |
入库方式： OAI收割
来源：生态环境研究中心
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