酸性吸附树脂对间苯二胺的吸附动力学及吸附热力学研究

Study on Adsorption Kinetics and Thermodynamics of M-Phenylenediamine onto Acid Adsorption Resins

摘要: 本文选取单宁酸、赖氨酸、氨基磺酸以及没食子酸四种官能团对树脂进行修饰，并通过静态吸附实验和吸附动力学实验，分别探讨这四种树脂对水中间苯二胺的吸附原理。实验结果表明：四种吸附树脂对间苯二胺均具有较好的吸附效果，经318K平衡吸附后降到288K (288K^*)时树脂对间苯二胺的吸附量最大，该过程包含物理吸附和化学吸附。四种吸附树脂对间苯二胺的吸附等温线符合Langmuir方程(R²均大于0.98)。热力学研究结果表明间苯二胺在LAS上的∆H是负值且其绝对值小于42 KJ/mol，说明此吸附过程是放热的过程，以物理吸附为主。另外三种树脂的∆H均为正值，说明吸附过程是一个吸热过程。准一级动力学方程的R₁²均大于0.99，表明间苯二胺在AJHS树脂上的吸附动力学过程更符合准一级动力学方程。

Abstract: In this paper, four functional groups of tannic acid, lysine, sulfamic acid and gallic acid were used to modify the resin. Through the static adsorption experiment and adsorption Kinetics experiment, the adsorption mechanism of these four resins to water phenylenediamine was discussed. The experimental results show that the four adsorption resins have good adsorption effect on m-phenylenediamine. At 288K^*, the adsorption of m-phenylenediamine by the resin is the largest. This process includes physical adsorption and chemical adsorption. Adsorption isotherm of m-phenylenediamine on four kinds of adsorption resin accorded with Langmuir equation (R² is all greater than 0.98). The results of thermodynamics show that the enthalpy ∆H of phenylenediamine on LAS is negative and its absolute value is less than 42 KJ/mol, indicating that this adsorption process is an exothermic process, mainly based on physical adsorption. The enthalpies ∆H of the other three resins are positive, indicating that the adsorption process is an endothermic process. The R₁² of the pseudo-first-order Kinetic equation is all greater than 0.99, indicating that the adsorption Kinetics of m-phenylenediamine on AJHS resin is more consistent with the pseu-do-first-order Kinetic equation.