摘要
以某铅蓄电池厂污染场地5个铅污染区域(WS、A、B、C及BZ)的土壤为研究对象,对土壤中铅全量及各形态含量进行分析.在0.1 mol.L-1EDTA,30 min,25℃相同条件下,使用超声波辅助化学洗脱(ultrasonic-assisted chemical extraction,UCE)与传统化学洗脱(conventional chemical extraction,CCE)两种不同的作用方式,对铅的去除效率进行比较,并对两种不同清洗方式后铅的形态变化进行了探讨.结果表明,UCE对铅的去除效率显著优于CCE.在CCE作用下,5份污染土壤WS、A、B、C、BZ铅的去除效率依次为10.06%、48.29%、48.69%、53.28%及36.26%,而UCE作用下铅的去除效率依次为22.42%、69.31%、71.00%、74.49%及71.58%,平均效率高出22%.通过对比两种清洗方式后土壤中的铅形态发现,酸可提取态在UCE作用后持平或有所降低,但CCE后使酸溶态有增高的趋势;对于铁锰氧化态,UCE对其有着极好的去除能力,可达98%左右,同时对有机物及硫化物结合态、残渣态也具有较好的去除能力.因此,UCE在化学萃取中的应用具有一定的可行性,是一种简单、极快速去除污染场地中重金属铅的增效手段.
This research chose five lead-contaminated sites of a lead-acid battery factory to analyze the speciation distribution and concentration of lead.Under the same conditions（0.1 mol.L-1 EDTA,30 min,25℃）,the removal effect of heavy metal was compared between ultrasonic-assisted chemical extraction（UCE） and conventional chemical extraction（CCE）,and the variation of lead speciation was further explored.The results showed that the lead removal efficiency of UCE was significantly better than CCE.The lead removal efficiency of WS,A,B,C and BZ was 10.06%,48.29%,48.69%,53.28% and 36.26% under CCE.While the removal efficiency of the UCE was 22.42%,69.31%,71.00%,74.49% and 71.58%,with the average efficiency higher by 22%.By comparing the speciation distribution of the two washing methods,it was found that the acid extractable content maintained or decreased after UCE,whereas it showed an increasing trend after CCE.The reduction effect of the reducible was as high as 98% by UCE.UCE also showed a more efficient reduction effect of the organic matter-sulfite bounded form and the residual form.Hence,it is feasible to improve the washing efficiency of heavy metal contained in soil by conducting the cleaning process with the help of ultrasonic wave,which is a simple and fast mean to remove lead from contaminated sites.
出处
《环境科学》
EI
CAS
CSCD
北大核心
2013年第9期3704-3708,共5页
Environmental Science
关键词
超声波辅助化学洗脱
传统化学洗脱
铅污染土壤
铅形态
增效洗脱
ultrasonic-assisted chemical extraction
conventional chemical extraction
lead-contaminated soil
lead speciation
efficiency elution
