改性小麦秸秆吸附Cu2＋的动力学和热力学研究  

Kinetic and Thermodynamic Research on Cu^(2+) Adsorption by Modified Wheat Straw

作　　者：龚志莲[1] 李勇 陈钰[2] 龚正君[2] 

机构地区：[1]西华大学能源与环境学院,成都610039 [2]西南交通大学地球科学与环境工程学院,成都610031

出　　处：《地球与环境》2014年第4期561-566,共6页Earth and Environment

基　　金：中央高校基本科研业务费专项资金资助(SWJTU09BR166)

摘　　要：本研究采用ZnCl2作为活化剂,用640W功率的微波照射5min的方法制备改性小麦秸秆。研究了改性小麦秸秆投加量、吸附时间、温度、pH对改性小麦秸秆吸附水溶液中Cu2+的影响,以及对其等温吸附特征、动力学和热力学进行了研究。试验结果表明:投加量为0.1g,pH为6,改性小麦秸秆对Cu2+有较好的吸附效果,吸附在10h后达到平衡。改性小麦秸秆对Cu2+吸附较好地符合Langmuir、Freundlich温吸附模型和准二级动力学方程,吸附过程中△G<0,说明属于自发反应。In this study,a sort of modified wheat straw by using ZnCl2 as an activating agent was used as the adsorbent to remove Cu2＋from aqueous solution.Removal of Cu2＋from aqueous solutions by sorption on wheat straw was investigated.The influences of pH,dosage,adsorption time and reaction temperature were investigated through dynamic tests.Adsorption isotherm models,thermodynamics models and kinetics models of the adsorption process between modified wheat straw and Cu2＋were systematically studied.The results showed that dosage=0.1g and pH=6are the optimum conditions for this absorption process.When adsorption time is more than 10 hours,this adsorption reaches equilibrium.The goodness of fitness was obtained with the Langmuir and Freundlich adsorption isotherms and the quasi-second order kinetics equation.The free energy value（△G）calculated from the Van,t Hoff equation was negative,indicating that Cu2＋adsorption was a spontaneous process.

关 键 词：CU2+ 改性小麦秸秆 等温吸附 动力学 热力学 

分 类 号：X703.1[环境科学与工程—环境工程]