温度和表面活性剂对土壤吸附柴油的影响

Influence of Temperature and Surfactants on Sorption of Diesel Oil by Soils

通过静态吸附实验,研究了不同温度下,柴油在土壤中的吸附行为,探讨了阴离子表面活性剂SDS和非离子表面活性剂Tween80对柴油吸附的影响。结果表明,Langmuir吸附方程对柴油在3种土样中的吸附等温线的拟合效果较好,3种土样吸附能力的大小顺序为轻粘土>中壤土>重壤土;温度升高不利于柴油在土壤中的吸附;SDS和Tween80均利于柴油在土壤表面的解吸,且SDS的解吸效果更好。柴油的吸附量随SDS浓度的升高而降低。当Tween80的浓度小于临界胶束浓度CMC时,柴油的吸附量随Tween80浓度的升高而升高;当Tween80的浓度等于或大于CMC时,吸附量随Tween80浓度的升高而降低。

Static sorption experiments were carried out to investigate the sorption of diesel oil by soils at different temperatures, and to analyze the influence of SDS and Tween80 on the sorption of diesel oil. The results indicated that although the affinity of diesel oil for three soils was different, the sorption isotherms of diesel oil on the three soils were all well described by the Langmuir model. The sorption capacity on the three soils from high to low was： light clay〉medium loam〉 dense loam. Sorption of diesel oil on the three soils decreased with the temperature increasing. Both SDS and Tween80 had a positive effect on desorption of diesel oil from soils, and SDS played a much more important role. The increase of SDS concentration was not favorable to sorption of diesel oil on Soil 3. When Tween80 concentration was lower than the critical micelle concentration （CMC）, the sorption capacity of diesel oil on Soil 3 increased with increasing Tween80 concentration; while, when the concentration of Tween80 was equal to or higher than CMC, the sorption capacity of diesel oil on Soil 3 decreased with increasing Tween80 concentration.