title: [Analysis of washing efficiency and change in lead speciation in lead-contaminated soil of a battery factory].
abstract: Lead-contaminated soil with different pollution load in a lead battery factory in the southwest of China was chosen as the research object, the lead content and speciation were analyzed, and different washing agents were screened. The lead washing efficiency and lead speciation were analyzed under different pH conditions, and the soil of different particle size was washed using different duration to determine the best washing time. The results showed that the soil of sites A and B in the factory was severely contaminated, the lead concentration reaching 15,703.22 mg x kg(-1) and 1747.78 mg x kg(-1), respectively, and the proportion of the active-state lead was relatively high, while the residue state accounted for only 17.32%, 11.64%, 14.6% and 10.2%. EDTA and hydrochloric acid showed the best extraction effect in the 5 washing agents tested, which included EDTA, hydrochloric acid, citric acid, rhamnolipid and SDS. Cleaning under acidic conditions could not only effectively extract the total amount of lead but also effectively reduce the environmental risk of active-state lead. pH 4-7 was suggested as the most appropriate condition. The cleaning effect of coarse sand and fine sand was good, while for washing powder clay, it is better to improve the process, with the optimal washing time determined as 240 min.
authors.affiliation: Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China. ilzdcf@sina.com
authors.forename: Bei
authors.initials: B
authors.lastname: Ren
authors.forename: Jin-lou
authors.initials: JL
authors.lastname: Huang
authors.forename: Ming-sheng
authors.initials: MS
authors.lastname: Miao
mesh_terms: D002681:China; D019343:Citric Acid; D052918:Environmental Restoration and Remediation / Q000379:methods*; D006851:Hydrochloric Acid; D007221:Industry; D007854:Lead / Q000737:chemistry*; D010316:Particle Size; D012822:Silicon Dioxide; D012987:Soil / Q000737:chemistry*; D012989:Soil Pollutants / Q000737:chemistry*
chemical_list: D012987:Soil; D012989:Soil Pollutants; D019343:Citric Acid; D007854:Lead; D012822:Silicon Dioxide; D006851:Hydrochloric Acid