非离子表面活性剂对柴油在水/土壤界面间吸附的影响

Effect of Nonionic Surfactants on Sorption of Diesel Oil on Interface Between Soil and Water

通过静态吸附实验,研究了北京土壤对非离子表面活性剂Brij30和Brij35的吸附行为,考察了温度和溶液pH值对Brij30和Brij35吸附的影响,探讨了非离子表面活性剂对柴油吸附的影响。结果表明,6种土样对Brij30的吸附等温线均较好地符合“S”型多分子层吸附,而对Brij35的吸附等温线均较好地符合Langmuir型单分子层吸附;6种土壤吸附能力的大小顺序为轻壤土>轻粘土>中壤土>砂壤土>重壤土>紧砂土。同一土壤中,Brij30的吸附量大于Brij35的吸附量。温度升高有利于Brij30和Brij35在土壤颗粒物上的吸附,溶液pH值的升高不利于Brij30和Brij35在土壤中的吸附。Brij30和Brij35对柴油的解吸率最高分别可达22.5%和58.1%,说明Brij30和Brij35均利于柴油在土壤表面的解吸,且Brij35的解吸效果更好。

Static adsorption experiments were carried out to investigate the adsorption of Brij30 and Brij35 on Beijing soils, to determine the effect of temperature and pH on sorption and analyze the effect of nonionic surfactants on adsorption of diesel oil. The results indicated that the adsorption isotherms of Brij30 on 6 soils were well described by the ＂S＂ model, while those of Brij35 were well described by the Langmuir model. The adsorption capacity of Brij30 and Brij35 on the 6 soils from followed the order： light loam〉light clay〉 medium loam〉 sand loam〉 dense loam and dense sand. On the same soil the adsorbed quantity of Brij30 was higher than that of Brij35. The temperature increasing was favorable to the adsorption of Brij30 and Brij35, while the increase ofpH was not. The desorption rates of diesel oil in the presence of Brij30 and Brij35 were 22.5%and 58.1%, respectively, showing that Brij35 played a much more important role in desorption than Brij30.