表面活性剂对硝基苯污染土壤的增效修复技术研究

在研究硝基苯和表面活性剂在土壤中吸附行为的基础上，探讨了表面活性剂对硝基苯在土壤中吸附的影响，并研究了不同表面活性剂对硝基苯污染土壤的增效修复效果。结果表明：i）在0—25mg·L^-1。浓度范围内，硝基苯在土壤中的吸附量与溶液中平衡浓度之间存在较好的线性关系，硝基苯在土壤中的吸附是以分配作用为主。ii）CTAB、SDBS和Tween80在土壤中的吸附等温线均近似为S形．且都在各自临界胶束浓度附近达到饱和吸附，饱和吸附量顺序为CTAB〉〉SDBS〉Tween80。一定浓度的硝基苯可以增加表面活性剂在土壤中的饱和吸附量。iii）在较低浓度的表面活性剂存在下，硝基苯的吸附量随着表面活性剂浓度升高而升高，而在高浓度表面活性剂存在下硝基苯吸附量随表面活性剂浓度升高而降低，其中SDBS对硝基苯吸附量的降低效果最为明显。iv）当应用表面活性剂对硝基苯污染土壤进行增效修复时，SDBS的修复效果最为显著。

The Study of Surfactant-enhanced Remediation of Nitrobenzene-contaminated Soil

Base on the study of the adsorbed mechanisms of nitrobenzene and three surfactants on soil, this paper discussed the effect of surfactants on adsorption of nitrobenzene on soil. We also used surfactants to remediate nitrobenzene-contaminated soil in laboratory. The results showed： i ） The relationship between the adsorption amount of nitrobenzene on soil and the equilibrium concentration was well linear within the concentration ranging from 0 to 25 mg·L^-1. The main way of adsorption of nitrobenzene on soil was partition progress, jj ） The adsorption isotherms of surfactants were hearly S-types. The saturated equilibrium concentration was close to its CMC. The saturated adsorption amount sequence of three surfactants on soil was CTAB〉〉SDBS〉Tween80. While nitrobenzene was added into soil solution, the saturated adsorption amount and the saturated equilibrium concentration were both increased, iii） The adsorption amount of nitrobenzene increased under the lower concentration of surfactant, and then decreased under the higher concentration of surfactant. SDBS had the best decreased effect among three surfactants, iv） While using the three surfactants to flush the nitrobenzene-contaminated soil, the result showed that SDBS had the best effect on removing nitrobenzene from the soil, which provided reference for the application of the surfactant-enhanced remediation of organic-contaminated soil.