改性花生壳对水中苯酚的吸附热力学与动力学研究  

Research on Adsorption Thermodynamics and Kinetics of the Modified Peanut Shells Adsorption Phenol from Water

作　　者：柴红梅[1] 越慧[1] 吕磊[1] 高楼军[1] 王璇[1] 

机构地区：[1]延安大学化学与化工学院陕西省化学反应工程重点实验室,陕西延安716000

出　　处：《安徽农业科学》2013年第1期260-262,共3页Journal of Anhui Agricultural Sciences

基　　金：陕西省自然科学基金项目(2011JM2007);延安大学自然科学重点基金项目(YDZ2012-09)

摘　　要：通过甲醛—硫酸混合液改性花生壳对苯酚的吸附试验,研究了改性花生壳吸附苯酚的最佳条件、吸附热力学和动力学特征。采用Langmuir和Freundlich等温线对平衡数据进行了线性拟合,结果表明,改性花生壳对苯酚的吸附平衡符合Freundlich等温方程。在294 K下,吸附焓变△H=-11.41 kJ/mol,自由能△G=-5.09 kJ/mol,熵变△S=-21.50 J/(mol.K),表明该吸附过程为自发进行的放热过程。其动力学行为更好地符合Lagergren准二级动力学模型。Through the experiment of phenol adsorption by formaldehyde and sulfuric acid mixture modified peanut hull, the best condition, adsorption thermodynamic and kinetic characteristics were studied. The isotherm parameters were estimated by linear regression analysis with Langnmir isotherm model and Freundlieh isotherm model. The equilibrium process was described well by the Freundlich isotherm model. The thermodynamics parameters include enthalpy changes （GH） -11.41 kJ/mol, Gibb＇ S free energy changes （A G） -5.09 kJ/mol,and en- tropy changes（AS） -21.50 J/（mol ~ K） respectively at 294 K. it was indicated that the adsorption thermodynamics of phenol on nanocom- posites is a spontaneous and exothermic process. The kinetics of the interactions showed better agreement with the Lagergren second order ki- netics.

关 键 词：改性花生壳 吸附 苯酚 热力学与动力学 

分 类 号：S181.3[农业科学—农业基础科学]