电阻加热活化过硫酸盐修复全氟辛酸污染土壤  

Electrical resistance heating activated persulfate for remediation of perfluorooctanoic acid-contaminated soil

作　　者：邬刘涛 詹明秀 付建英[3] 焦文涛[2] 单永平 张晨琛 徐旭 WU Liu-tao;ZHAN Ming-xiu;FU Jian-ying;JIAO Wen-tao;SHAN Yong-ping;ZHANG Chen-chen;XU Xu(College of Metrology and Measurement Engineering,China Jiliang University,Hangzhou 310018,China;Research Center for Eco-Environmental Sciences,Chinese Academy of Sciences,Beijing 100085,China;State Key Laboratory of Clean Energy Utilization,Institute for Thermal Power Engineering,Zhejiang University,Hangzhou 310027,China)

机构地区：[1]中国计量大学计量测试工程学院,浙江杭州310018 [2]中国科学院生态环境研究中心,北京100085 [3]浙江大学热能工程研究所,能源高效清洁利用全国重点实验室,浙江杭州310027

出　　处：《浙江大学学报（工学版）》2023年第6期1257-1266,共10页Journal of Zhejiang University：Engineering Science

基　　金：国家自然科学基金资助项目(42077126)。

摘　　要：为了有效去除污染土壤中的全氟辛酸(PFOA),通过电阻加热(ERH)活化过硫酸盐(PS)的方法,研究3种土壤(壤土、砂土和黏土)在ERH-PS耦合修复过程中的升温规律和PFOA的去除效果.以黏土为代表土壤,探究氧化剂添加量、土壤初始pH和共存氯离子对土壤中PFOA去除的影响以及PFOA的降解机制.研究结果表明,当电压强度为3 V/cm时,3种土壤由25℃升至100℃的时间均不超过30 min.每千克土壤添加50 g PS、加热温度为100℃,降解6 h后,3种土壤的PFOA降解效率由大到小依次为黏土(90.9%)>壤土(72.7%)>砂土(48.8%). PS的添加量是保证土壤中PFOA有效降解的重要条件,土壤的酸性环境有利于促进PFOA的降解,碱性条件和共存氯离子均会抑制PFOA的降解.通过对降解中间产物的检测分析,进而推断PFOA可能的降解机理为PS活化生成的SO_(4)^(·-)和·OH促使的PFOA逐级降解过程.In order to effectively remove perfluorooctanoic acid(PFOA)from contaminated soil,electrical resistance heating(ERH)activated persulfate(PS)was used to study the heating law and PFOA removal effect of three different soils(loam,sandy soil and clay)during the ERH-PS coupled remediation process.Taking clay as the representative soil,the effect of amount of oxidant added,initial soil pH,and coexisting chloride ions on PFOA removal and the degradation mechanism of PFOA in soil were further studied.Results showed that when the voltage intensity was 3 V/cm,the time for the three soils to rise from 25℃to 100℃did not exceed 30 minutes.When the amount of PS added per kilogram of soil was 50 g,the heating temperature was 100℃,and after 6 h of degradation,the degradation efficiency of PFOA for the soils was as follows:clay(90.9%)>loam(72.7%)>sandy soil(48.8%).In the meanwhile,PS addition was an important condition to ensure the effective degradation of PFOA in soil.The acidic environment of soil was favorable to promote the degradation of PFOA,while the alkaline conditions and coexisting chloride ions would inhibit the degradation of PFOA.Through the detection and analysis of the degradation intermediates,it is inferred that the possible degradation mechanism of PFOA was the step-by-step degradation process of PFOA promoted by SO_(4)^(·-) and ·OH generated by PS activation.

关 键 词：全氟辛酸(PFOA) 土壤修复 电阻加热(ERH) 过硫酸盐 降解效果 

分 类 号：X53[环境科学与工程—环境工程]