土壤有机质形态对有机污染物三氯乙烯(TCE)的吸附影响研究

Effect of the Organic Matter in Soil on the Adsorption of the Organic Pollutant——Trichloroethene

[目的]研究有机质形态对有机污染物在环境中的迁移、转化等过程产生的影响。[方法]采用北京某地区3种土壤的三级样品,即原样土作为一级土壤,使用双氧水去除原样土中低聚合"软碳"的二级土壤和根据土壤样品测得的有机碳含量,使用高岭土代替无机矿物,利用腐殖质做"软碳",按比例配制而成的三级土样;利用批试验的方法研究土壤样品对TCE的吸附行为。[结果]研究表明,土壤样品中,由于有机碳含量不同,有机污染物三氯乙烯的吸附量不同,样品吸附具有较好的线性行为,试验范围内不存在饱和吸附量;有机质吸附量大于无机矿物吸附量,一级土样和二级土样吸附TCE的能力基本相同,即土样有机碳聚合形式的差异对TCE吸附能力影响较小。[结论]影响土样吸附TCE的主要因素是有机碳含量。

[ Objective] The effect of organic pollutants on the process of the migration and conversion of organic pollutants in the environment was studied. [ Method] The three-classification of soil samples in Beijing area was collected and the first classification of soil sample was original soil sample ; the second classification, the soil with the low aggregation of ＂soft carbon＂ removed from original soil with hydrogen peroxide ; and the third classification, the soil consisting of the kaolin instead of inorganic mineral and the humus instead of ＂soft carbon＂ according to the proportion after the content of organic carbon in soil was measured. The adsorption behavior of soil samples to TCE was tested. [ Results] The result showed that the adsorption of soil sample to TCE was variable with the difference of its content of organic carbon, the adsorption of the soil to TCE was with the line adsorption behavior and there was no saturated adsorption capacity in experimental range. The adsorption capacity of organic matter was larger than that of inorganic minerals and there was basical same adsorption capacity of the first and second classification of soil sample to TCE, which indicated that the polymer of organic carbon in soil less affected of adsorption capacity of it to TCE. [ Conclusion] The content of organic carbon in soil was the major factor impacting its adsorption to TCE.