Ma Xiaodong, Zheng Minghui, Liu Wenbin, Qian Yong, Zhao Xingru, Zhang Bing
Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, P.O. Box 2871, Beijing 100085, China.
Chemosphere. 2005 Aug;60(6):796-801. doi: 10.1016/j.chemosphere.2005.04.021.
Dechlorination of hexachlorobenzene (HCB) was achieved by a mixture of commercial CaO and alpha-Fe2O3 (CaO/alpha-Fe2O3) in closed systems at temperatures of 300 degrees C and 350 degrees C, which exhibited a synergic effect compared to CaO or alpha-Fe2O3 alone, and the dechlorination efficiency was dramatically enhanced. When CaO and alpha-Fe2O3 coexisted, HCB was dechlorinated by about 98% after 0.5 h reaction at 300 degrees C. All TeCB-, TrCB-, and DCB-isomers were detected, showing the presence of more than one dechlorination pathway. The pathway to form 1,2,4-TrCB must be a major pathway because the greatest amount of 1,2,4-TrCB was detected. There existed discrepancy of the material balance between the starting and dechlorinated materials. It implies that besides dechlorination other decomposition processes may be present. The mechanism of synergic effect of calcium and iron oxides was investigated.
在封闭系统中，通过商业氧化钙（CaO）和α-三氧化二铁（α-Fe₂O₃）的混合物（CaO/α-Fe₂O₃）在300℃和350℃的温度下实现了六氯苯（HCB）的脱氯，与单独的CaO或α-Fe₂O₃相比，其表现出协同效应，脱氯效率显著提高。当CaO和α-Fe₂O₃共存时，在300℃下反应0.5小时后，HCB的脱氯率约为98%。检测到了所有的四氯苯（TeCB）、三氯苯（TrCB）和二氯苯（DCB）异构体，表明存在不止一种脱氯途径。形成1,2,4-三氯苯的途径一定是主要途径，因为检测到的1,2,4-三氯苯量最大。起始物料和脱氯后物料之间存在物料平衡差异。这意味着除了脱氯之外，可能还存在其他分解过程。对钙和铁氧化物的协同效应机制进行了研究。
