硝基苯在土壤中的吸附特征及影响因素

Absorption Characteristics and Influencing Factors of Nitrobenzene in Soil

为全面了解硝基苯的环境行为,对硝基苯在土壤中的吸附行为及影响因素进行了研究。结果表明:土壤中硝基苯的吸附平衡时间为6 h,其吸附等温线可用Freundlich模型描述;硝基苯在土壤中的吸附自由能的变化<40 kJ/mol,表明土壤对硝基苯的吸附以物理吸附为主;土壤对硝基苯的吸附量随温度的升高而减少;酸性条件能抑制土壤对硝基苯的吸附作用,而在土壤溶液pH≥7时,土壤对硝基苯吸附基本不受pH变化所影响。

An experiment was conducted to study the adsorption characteristics of nitrobenzene in soil adsorption to comprehensively understand environmental behaviors of of nitrobenzene.The results showed that the adsorption was in balance when adsorption time was over 6 hours.Adsorption isotherms were fitted to the Freundlich models.Adsorption free energy changed in less then 40 kJ/mol,which showed that the physical adsorption was predominant.The nitrobenzene adsorptive capacity reduced along with the temperature ascension.In acidic conditions the adsorption of nitrobenzene was inhibited in soil.In the soil solution of pH≥7, the nitrobenzene absorption of soil was not affected.