醇类淋洗剂淋洗修复多环芳烃污染土壤

摘要

异位土壤淋洗技术是一种有效的污染土壤修复技术.以菲和苯并[a]芘为目标污染物,选取醇类作为淋洗剂,考察了醇种类及浓度、淋洗剂用量、淋洗时间、淋洗温度、淋洗次数对污染土壤(菲和苯并[a]芘质量浓度分别为82.5、4.3 mg/kg)淋洗效果的影响.结果表明:修复的最佳条件为正丙醇体积分数40％、淋洗剂用量20 mL、淋洗温度20℃、淋洗时间60 min、重复淋洗2次,此时菲和苯并[a]芘的去除率分别达到93.05％、86.85％.%Ex-situ soil washing technology is an effective remediation technology for contaminated soil.Phenanthrene and benzo[a]pyrene were taken as target pollutants and alcohols were taken as eluant agent.A series of experiments were conducted to study the effects of the variety and concentration of alcohols,eluant agent volume,washing time,washing temperature and washing cycles on the removal rate for the contaminated soil (the mass concentrations of phenanthrene and benzo[a]pyrene were 82.5 and 4.3 mg/kg,respectively).Results showed that the best conditions for remediation were 40％ (volume fraction) of 1-propanol as eluant agent,eluant agent volume of 20 mL,washing temperature of 20 ℃,washing time of 60 min and repeat twice.Under the best conditions,phenanthrene and benzo[a]pyrene removal rates could reach 93.05％ and 86.85％,respectively.