化学氧化修复PAHs污染土壤的性质及毒性变化

采用室内模拟实验研究了过氧化氢、类Fenton试剂、活化过硫酸钠对人工模拟菲、芘污染土壤的去除效果，以及处理后土壤中有机质(SOM)含量、过氧化氢酶(CAT)活性及土壤的植物毒性变化。结果表明化学氧化修复能降低多环芳烃（PAHs）污染土壤的植物毒性，减低土壤中的污染物浓度。经活化过硫酸钠处理，黑麦草种子的发芽率由41%提高到93%以上，对菲和芘的降解率均可达97%以上；经类Fenton试剂处理，黑麦草种子的发芽率由41%提高到88%以上，对菲和芘的降解率均可达87%以上；经过氧化氢处理，黑麦草种子的发芽率由41%提高到80%以上，对菲和芘的降解率均可达72%以上。分析原因可能是3种氧化剂处理后土壤中PAHs的浓度显著下降，降低了其毒性。

Changes in polyaromatic hydrocarbons contaminated soil properties and phytotoxicity under chemical oxidation

Different oxidants have been evaluated for the removal of polycyclic aromatic hydrocarbons(PAHs) from contaminated soils using a simulation device.The soil organic matter(SOM),catalase activity(CAT),and seed germination ratio(GI)were investigated under different treatments.When activated persulfate was added,the removal ratios of phenanthrene and pyrene were more than 97% and the GI was raised from 41% to 93%.Under modified Fenton reagent treatment,the GI was raised from 41% to 88%,and the removal of phenanthrene and pyrene reached 87%.Under hydrogen peroxide treatment,the GI was raised from 41% to 80%,and the removal of phenanthrene and pyrene reached 72%.The results indicated that chemical remediation can reduce the phytotoxicity of contaminated soil and this maybe because most of the PAHs were oxidized during such treatment.