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采用批量试验的方法研究了西北地区黄土对克百威的吸附动力学和热力学行为,并对相关影响因素进行了分析。结果表明:黄土对克百威吸附的最优动力学方程为准二级动力学方程;克百威在黄土中的吸附较好地符合Freundlich等温吸附方程;黄土吸附克百威过程中的吉布斯自由能ΔG■、焓变ΔH■及熵变ΔS■都小于0,表明黄土对克百威的吸附为自发进行的放热过程,并且吸附过程中体系混乱度减小,黄土吸附克百威的主要作用力为氢键力;pH值为4~10时,随pH值增大克百威的吸附容量减小,且pH值为4~8时减小趋势较平缓,p H值为8~10时减小趋势很大;随供试土样粒径减小,克百威在黄土中的吸附容量增大,当土壤粒径从0.45 mm减小到0.075 mm时,吸附容量由0.009 mg/g增加到0.049 mg/g;克百威在黄土中的吸附容量受其初始质量浓度影响很大,随克百威初始质量浓度增大,黄土对其的吸附容量相应增加,克百威初始质量浓度从20 mg/L增至110mg/L时,其在黄土中的吸附容量从0.080 mg/g增加至0.206 mg/g。
The batch test method was used to study the adsorption kinetics and thermodynamic behavior of carbofuran from loess in Northwest China. The influencing factors were also analyzed. The results show that the optimal kinetic equation for the adsorption of carbofuran in loess is quasi-second-order kinetic equation; the adsorption of carbofuran in loess is in good agreement with the Freundlich adsorption equation; the adsorption of carbofuran in loess The free energy ΔG ■, enthalpy change ΔH ■ and entropy change ΔS ■ are all less than 0, indicating that the adsorption of carbofuran in loess is spontaneous exothermic process, and the chaos of the system decreases during the adsorption process. Of the main force for the hydrogen bonding force; pH value of 4 to 10, with the increase of pH, the adsorption capacity of carbofuran decreases, and the pH value of 4 to 8 when the decrease of the trend is relatively flat, p H value of 8 ~ 10. The adsorption capacity of carbofuran in loess increased with the decrease of particle size of soil samples. When the particle size decreased from 0.45 mm to 0.075 mm, the adsorption capacity increased from 0.009 mg / g increased to 0.049 mg / g. The adsorption capacity of carbofuran in loess was greatly influenced by its initial mass concentration. With the increase of initial mass concentration of carbofuran, the adsorption capacity of loess increased accordingly, When the mass concentration increased from 20 mg / L to 110 mg / L, its adsorption capacity in loess increased from 0.080 mg / g to 0.206 mg / g.