固液界面吸附热力学参数的计算  

Calculation of Adsorption Thermodynamic Parameters at Solid-liquid Interfaces

作　　者：那立艳 张丽影 张凤杰 华瑞年 NA Liyan;ZHANG Liying;ZHANG Fengjie;HUA Ruinian(College of Life Science,Dalian Minzu University,Dalian 116600,China;College of Environment and Bioresources,Dalian Minzu University,Dalian 116600,China)

机构地区：[1]大连民族大学生命科学学院,大连116600 [2]大连民族大学环境与资源学院,大连116600

出　　处：《材料导报》2020年第22期22030-22035,共6页Materials Reports

基　　金：国家自然科学基金(31770502);辽宁省自然科学基金(201602203,20180550977)。

摘　　要：目前全球水体污染问题日趋严重,给人类健康及生态环境带来很大危害。吸附分离方法因具有高效、低成本、操作简便和环境友好等特点成为最常使用的污水净化技术。吸附过程中热力学参数(吉布斯自由能变ΔG 0、焓变ΔH 0及熵变ΔS 0)的测定对有效评估吸附性能及预测反应机制具有十分重要的作用,目前文献报道中吸附热力学参数的计算方式非常混乱、结果可靠性较差,主要原因在于对标准平衡常数无量纲特性的理解不够深刻。Langmuir方程是应用最为广泛的等温吸附方程,通过对吸附过程中标准平衡常数(K 0)和Langmuir平衡常数(K L)的推导,明确了二者的物理意义及相互转换关系,并对文献报道中存在的问题进行了总结和更正,希望能够对吸附过程热力学参数的获得提供有效的借鉴。Water pollution is an increasingly serious problem the world is facing today,causing damage to human health and ecological environment.Adsorption is one of the most commonly used techniques for water purification due to its high efficiency,low cost,easy operation and environmental benign properties.Thermodynamic parameters such as the Gibbs free energy change(ΔG 0),enthalpy change(ΔH 0)and entropy change(ΔS 0)are critical in estimating the performance and predicting the mechanism of an adsorption process.In the adsorption literature,thermodynamic parameters are usually improperly calculated,and the results are unreliable.The reason is the standard equilibrium constant for calculationΔG 0 must be a dimensionless parameter.The Langmuir equation is the most widely used isotherm equation in the adsorption process.By deducing the standard equilibrium constant K 0 and the Langmuir equilibrium constant K L,the physical significances of the two parameters were identified and the conversion relationship between them were discussed.Moreover,the existing problems in the literature were summarized and corrected.This study attempts to shed light on the proper estimation of thermodynamic parameters in the adsorption process.

关 键 词：LANGMUIR 方程 经验平衡常数 标准平衡常数 热力学参数 

分 类 号：O6-04[理学—化学]