动力学、热力学和活化能在花生壳吸附铅离子实验中的应用  

Application of Kinetics,Thermodynamics and Activation Energy in Adsorption of Pb2+by Peanut Shell

作　　者：林晨曦 冯洋 李晴 任艳梅 李银辉 LIN Chen-Xi;FENG Yang;LI Qing;REN Yan-Mei;LI Yin-Hui(School of Chemical Engineering and Technology,Hebei University of Technology,Tianjin 300130,China;China Engineering Research Center of Seawater Utilization Technology,Ministry of Education,Tianjin 300130,China;National-Local Joint Engineering Laboratory for Energy Conservation of Chemical Process Integration and Resources Utilization,Tianjin 300130,China)

机构地区：[1]河北工业大学化工学院,天津300130 [2]海水资源高效利用化工技术教育部工程研究中心,天津300130 [3]化工节能过程集成与资源利用国家地方联合工程实验室,天津300130

出　　处：《化学教育（中英文）》2020年第8期53-57,共5页Chinese Journal of Chemical Education

基　　金：河北省自然科学基金(B2016202271);河北工业大学教育教学改革项目(201704048);河北工业大学优质课建设项目(YK2018057)。

摘　　要：以花生壳为吸附剂、Pb2+为模拟污染物研究了物理化学中固体表面的吸附过程,考察了Pb2+的初始浓度、吸附温度的影响,研究了固体表面吸附反应动力学、热力学和活化能。结果表明:在不同Pb2+初始浓度下,Pb2+在花生壳表面的吸附动力学符合准二级动力学模型,表明该吸附过程是化学吸附为控制步骤的吸附过程。热力学结果表明Pb2+在花生壳表面的吸附是一个自发的放热过程,因为Pb2+由三维运动转变为二维运动导致系统熵减小。活化能Ea=31.35 kJ·mol-1再次证明Pb2+在花生壳表面的吸附是化学吸附过程,这些结果较好地验证了物理化学教学中固体表面的吸附行为。通过该拓展实验加深了学生对固体表面吸附过程的理解,同时,培养了学生的科技创新能力。The adsorption process of solid surface in physical chemistry was studied with peanut shell as the adsorbent and Pb2+as the simulated pollutant.The effects of Pb2+initial concentration and adsorption temperature were investigated.The kinetics,thermodynamics and activation energy of adsorption reaction on solid surface were studied.The results showed that the adsorption kinetics of Pb2+on peanut shell surface was in accordance with the pseudo-second-order kinetic model at different Pb2+initial concentration.It is shown that the adsorption process was an adsorption process in which chemical adsorption was the control step.Thermodynamics results showed that Pb2+adsorption on peanut shell surface was a spontaneous exothermic process and the entropy of the system decreased because Pb2+changed from three-dimensional motion to two-dimensional motion.Activation energy Ea=31.35 kJ·mol-1 proved again that the adsorption of Pb2+on the surface of peanut shell was a chemical adsorption process.These results verified the adsorption behavior of solid surface in physical chemistry teaching well.Students’understanding of solid surface adsorption process was deepened through the expansion experiment.At the same time,the ability of scientific and technological innovation of students was cultivated.

关 键 词：物理化学实验 反应动力学 热力学 活化能 吸附 

分 类 号：O647.33-4[理学—物理化学] G642[理学—化学]