生物炭对邻苯二甲酸二甲酯在土壤中自然降解和吸附行为的影响

为了解生物炭应用于邻苯二甲酸酯污染土壤修复的可行性，选择邻苯二甲酸二甲酯作为目标污染物，以花生壳为原料制备生物炭，通过室内模拟试验研究生物炭对邻苯二甲酸二甲酯在土壤中自然降解和吸附行为的影响。结果表明，未添加与添加生物炭土壤中邻苯二甲酸二甲酯的自然降解过程均遵循一级动力学方程，生物炭含量0.5%和1.0%的土壤中邻苯二甲酸二甲酯的半衰期分别延长2.185 d和4.151 d，表明添加生物炭会不同程度地延缓土壤中邻苯二甲酸二甲酯的自然降解；在不同的生物炭含量水平下，土壤对邻苯二甲酸二甲酯的吸附均能很好地符合Freundlich方程所描述的规律，生物炭含量0.1%、0.5%和1.0%土壤的吸附常数Kf分别为35.647、45.830和57.649，显著高于对照土壤（7.793），表明土壤对邻苯二甲酸二甲酯的吸附作用随生物炭含量增加而显著增强。

Effect of natural degradation and adsorption of dimethyl phthalate by adding biochar to soil

In order to understand feasibility of biochar applied to soil remediation to phthalates esters,dimethyl phthalate was chosen as target pollutant,and peanut shell was used as raw material of biochar to study the natural degradation and adsorption laws of biochar to the soil pollutant through laboratory simulation experiment.The results indicated that natural degradation processes of dimethyl phthalate in soil with and without biochar both fitted the first-order kinetics equation.Compared with soil without biochar,the half-life period of dimethyl phthalate in soil with biochar of 0.5% and 1.0% delayed 2.185 d and 4.151 d,respectively.That meant addition of biochar into soil could delay natural degradation of dimethyl phthalate.Furthermore,adsorption of soil with different biochar contents to the pollutant all followed Freundlich equation.The adsorption constants Kf of soil with 0.1%,0.5% and 1.0% were 35.647,45.830 and 57.649,respectively,which were all larger than the control (7.793).The adsorption capacity of soil to dimethyl phthalate obviously enhanced with increasing content of biochar.