Abstract: Humic acid was alkylated and sulfomethylated to prepare modified humic acid named MHA12、MHA16 and MHA18. The structure of modified humic acid was identified by IR. The critical micelle concentrations were obtained by measuring the surface tension of MHA with different concentrations. The solubilization capacities on naphthalene (Nap)，phenanthrene (PhA)，fluoranthene (FluA)，pyrene (Pyr) in contaminated soil were studied. The results showed that alkyl groups and sulfomethyl groups were introduced in the modified humic acid. It was found that modified humic acid had good solubility and surface activity. The critical micelle concentration (CMC) of MHA12、MHA16、MHA18 was 3.12 g/L、2.78 g/L and 2.70 g/L respectively. MHA12、MHA16、MHA18 had good solubilization capacity on Nap，PhA，FluA，Pyr while the concentration of MHA exceeded CMC. The modified humic could be used for the repair of polycyclic aromatic hydrocarbons（PAHs） in contaminated soil.

Key words: humic acid, alkylated, sulfomethylated, surface activity, CMC, polycyclic aromatic hydrocarbons(PAHs), washing effect

摘要： 以黑腐酸为原料，进行烷基化反应和磺甲基化反应，得到改性黑腐酸MHA12、MHA16和MHA18。用IR测定了改性物的结构，通过测定不同浓度下改性黑腐酸溶液的表面张力得到改性黑腐酸的临界胶团浓度CMC，并测定了MHA12、MHA16、MHA18对PAHs污染土壤中萘、菲、荧蒽、芘的洗脱效率。结果表明：黑腐酸经过改性后引入了烷基基团和磺甲基基团，具有较好的水溶性和表面活性，MHA12、MHA16、MHA18的临界胶团浓度分别为3.12 g/L、2.78 g/L、2.70 g/L。当MHA溶液浓度超过临界胶团浓度时，MHA12、MHA16和MHA18对萘、菲、荧蒽、芘都具有良好的洗脱能力，可用于多环芳烃污染土壤的修复。

关键词: 黑腐酸, 烷基化, 磺甲基化, 表面活性, 临界胶团浓度, 多环芳烃, 洗脱