Fe2+活化过硫酸钠原位修复氯苯污染地下水

通过建立土槽模型模拟实际污染场地,并采用Na2S2O8为氧化剂、柠檬酸螯合Fe2+为活化剂,研究了氯苯在地下水中的迁移分布规律、原位修复及其对地下水环境的影响。结果表明,氯苯在含水层水平纵向上的迁移作用大于横向迁移;随着时间的增加,地下水中氯苯浓度变化总趋势为先增加后减少并最终趋于稳定;随着迁移距离的增加,氯苯的浓度逐渐降低。柠檬酸螯合Fe2+活化Na2S2O8能够有效修复受氯苯污染的地下水和土壤;持续氧化36 h后,地下水和土壤中氯苯的去除率分别达到82.4%和80.3%。进一步研究发现,氧化处理后,出水的pH值基本稳定在3.5、SO42-浓度为88.7 mg/L,满足地下水Ⅱ类水质标准。

Sodium persulfate activation by Fe2+ for the in situ remediation of chlorobenzene-contaminated groundwater

To investigate the migration, distribution, and removal of chlorobenzene in groundwater, and the effect of in-situ remediation on the groundwater environment, a soil tank model was developed to simulate actual pollution sites. Sodium persulfate and citric acid chelated with Fe2+ were used as the oxidant and activating agent, respectively. The results showed that the longitudinal dispersion of chlorobenzene in aquifers was much greater than the transverse diffusion, and the temporal change to chlorobenzene in groundwater increased at first, then decreased, and finally stabilized. However, the concentration of chlorobenzene decreased as the migration distance increased. Sodium persulfate, activated by citric acid chelated with Fe2+, could remove chlorobenzene effectively, and the maximum degradation rates for chlorobenzene in groundwater and soil were 82.4% and 80.3%, respectively, within 36 h of treatment. Further investigations showed that the final effluent pH value was 3.5 and the SO42- concentration was 88.7 mg/L, which met the grade II groundwater quality standard.