洗脱–过硫酸钠氧化联合去除土壤中PCBs的研究  

Combination of Elution and Persulfate Oxidation for the Removal of PCBs from Soils

作　　者：朱长银[1,2] 方国东[2] 司友斌[1] 周东美[2] 

机构地区：[1]安徽农业大学资源与环境学院,合肥230036 [2]中国科学院土壤环境与污染修复重点实验室(南京土壤研究所),南京210008

出　　处：《土壤》2015年第6期1125-1131,共7页Soils

基　　金：国家重点基础研究发展计划项目(2013CB934303);高校博士点专项科研基金项目(20133418110004)资助

摘　　要：考察了羟丙基-β-环糊精(HPCD)及聚氧乙烯月桂醚(Brij35)洗脱和过硫酸钠(SPS)氧化联合对模拟污染土壤以及场地污染土壤中多氯联苯(PCBs)的去除效果,探讨了洗脱时间、土液比和洗脱剂浓度对土壤中PCBs洗脱率和过硫酸钠浓度对洗脱液中PCBs降解效率的影响。结果表明:两种洗脱剂都能有效地洗脱模拟污染土壤中的2,4,4?-三氯联苯(PCB28),在土液比为1︰20,HPCD和Brij35浓度分别为20 g/L和8.0 g/L时,洗脱4 h后,土壤中PCB28的洗脱率分别可达90%和79%;用100 g/L的SPS氧化24 h后,PCB28的最大去除率分别可达90%和92%。将PCB28模拟污染土壤洗脱-过硫酸钠氧化的优化条件用于去除场地污染土壤中的PCBs(总浓度约1 400 mg/kg),发现HPCD和Brij35对PCBs的总洗脱率分别为66%和53%;SPS处理后,两种洗脱液中PCBs(10.6 mg/L)的总降解率分别为41%和52%。由此,洗脱-过硫酸钠氧化法能快速有效去除污染土壤中的PCBs,为PCBs场地污染土壤修复提供了一种新的方法。This paper investigated the removal of polychlorinated biphenyls （PCBs） in the simulated and site contaminated soils with the combined method of elution with hydroxypropyl-β-cyclodextrin （HPCD） and polyoxyethylene lauryl ethe （Brij35） and sodium persulfate （SPS） oxidation. The effects of elution time, soil/liquid ratio and eluent concentration on the elution efficiency of PCBs from the soil as well as the effect of SPS concentration on the degradation of PCBs in elution were examined. Results indicated that 90% and 79% of PCB28 was eluted from simulate contaminated soil with soil/liquid ratio of 1 ： 20, elution time of 4 h, and 20 g/L of HPCD and 8.0 g/L of Brij35, respectively. After that, the elution was oxidized by persulfate for 24 h and 90% and 92% of PCB28 were degraded by 100 g/L SPS in HPCD and Brij35 elutions, respectively. Furthermore, HPCD or Brij35 elution combined with persulfate oxidation processes was also applied for the removal of PCBs in site contaminated soils, which contained approximately 1400 mg/kg of PCBs. The results indicated that 66% and 53% of PCBs were removed from the soils with the optimum conditions. Similarly, persulfate also exhibited excellent ability to degrade PCBs in HPCD and Brij35 elutions, and about 41% and 52% of 10.6 mg/L PCBs were degraded in the presence of 100 g/L persulfate within 24 h. This study developed an efficiently method for the removal of PCBs from soils, and provided a new strategy for the remediation of PCBs contaminated soils.

关 键 词：多氯联苯 羟丙基.B.环糊精 聚氧乙烯月桂醚 洗脱 过硫酸钠氧化 

分 类 号：X53[环境科学与工程—环境工程]