无机沉淀对土壤有机质吸附疏水有机污染物的影响

Effect of Inorganic Ion Precipitation on Hydrophobic Organic Pollutant Adsorption by Non-extracted Soil Organic Matters

土壤有机质对疏水性有机污染物的吸附解吸是影响其在土壤中迁移、转化和归趋的重要因素之一。老化是有机污染物和土壤等介质长时间相互作用的结果,它影响着污染物的生物有效性。已有的老化研究注重有机污染物被土壤等介质吸附隔离的机制,很少考虑土壤等吸附剂自身演化对有机污染物吸附的影响。本文通过无机沉淀处理方法来模拟自然环境过程吸附剂自身的演化对土壤有机质吸附能力的影响,从而证明吸附剂自身的变化也是影响老化效应的一个重要因素。结果表明,不同无机沉淀包裹和填充的碱提土样品比原始碱提土样品具有更小的吸附能力,同时无机沉淀处理后的样品的吸附性能随着无机沉淀离子浓度增加而降低。这可能是无机沉淀覆盖碱提土样品的内外表面积和填充碱提土样品的微孔所引起的,同时也可能是无机沉淀占据了吸附有机污染物的高能点位所致。

Hydrophobic organic pollutant adsorption by non-extracted soil organic matters was an important factors which affected the migration,transformation and fate of hydrophobic organic pollutants in soil. Aging was the results of organic pollutants interaction with soil for a long time,which influenced bioavailability of organic pollutant. Prior studies on aging of hydrophobic organic pollutants paid more attention to the mechanism of adsorption sequestration,but the variation of adsorbent themselves was rarely considered under natural condition. The research results show that alkali extract soil by different precipitate packaged and filled has smaller adsorption ability than original samples,and meanwhile the adsorption property decrease with increasing ion concentration of inorganic precipitate. The reason may be that the inner and outer surface areas of alkali extract soil are covered and the microspores are filled with inorganic precipitate; or the high energy sites to adsorb organic pollutant are occupied by inorganic precipitate.