Beijing Key Laboratory for Risk Modeling and Remediation of Contaminated Sites, National Engineering Research Center of Urban Environmental Pollution Control, Beijing Municipal Research Institute of Eco-Environmental Protection, Beijing, 100037, China.
Environ Geochem Health. 2023 Jun;45(6):3971-3983. doi: 10.1007/s10653-023-01479-x. Epub 2023 Jan 11.
It is well known that many chlorinated organic pollutants can be dechlorinated by nanoscale zero-valent iron. However, in the real chlorinated organic compounds contaminated soil, the congeners of high- and low-chlorinated isomer often coexist and their dechlorination behaviors are poorly known, such as hexachlorobenzene (HCB). In this work, the degradation behaviors of three coexisting chlorobenzene congeners pentachlorobenzene (PeCB), 1,2,4,5-tetrachlorobenzene (1,2,4,5-TeCB) and 1,2,4-trichlorobenzene (1,2,4-TCB) and the influence of initial pH and reaction temperature on the dechlorination of HCB in HCB-contaminated soil by nanoscale zero-valent iron were studied. The amount and extent of accumulated coexisting chlorobenzenes was analyzed under different environmental conditions. The results indicate that nanoscale zero-valent iron can improve the degradation efficiency of highly toxic chlorinated benzenes and reduce the accumulative effects of highly toxic chlorinated benzenes on dechlorination of HCB. The accumulative effects of three coexisting chlorobenzene congeners on the dechlorination of HCB were ranked as follows: 1,2,4-TCB > 1,2,4,5-TeCB > PeCB.
众所周知，许多含氯有机污染物可以被纳米零价铁脱氯。然而，在真实的被氯代有机化合物污染的土壤中，高氯和低氯同系物往往共存，它们的脱氯行为知之甚少，如六氯苯（HCB）。在这项工作中，研究了三种共存的氯苯同系物五氯苯（PeCB）、1,2,4,5-四氯苯（1,2,4,5-TeCB）和 1,2,4-三氯苯（1,2,4-TCB）在纳米零价铁存在下的降解行为，以及初始 pH 值和反应温度对 HCB 污染土壤中 HCB 脱氯的影响。在不同的环境条件下分析了共存氯苯的积累量和程度。结果表明，纳米零价铁可以提高高毒性氯苯的降解效率，降低高毒性氯苯对 HCB 脱氯的累积效应。三种共存氯苯同系物对 HCB 脱氯的累积效应依次为：1,2,4-TCB>1,2,4,5-TeCB>PeCB。
