H-103树脂吸附氯离子的热力学研究

Thermodynamic study on adsorption of chlorine ions by H-103 resin

本文研究了H-103大孔树脂吸附废水中Cl-的热力学特性。研究结果表明:H-103树脂吸附废水中Cl-符合Freundlich等温吸附方程,方程拟合不同温度下Kf值的变化不大,说明温度对吸附量影响很小,拟合得到的Freundlich方程参数n值均大于1,表明H-103树脂吸附氯离子属于优惠吸附;吸附焓变ΔH<0,表明氯离子在H-103树脂上的吸附为放热过程;但ΔH<5kJ·mol-1,焓变值很小,表明温度对吸附影响不明显,同时也表明吸附过程不存在配位基交换或化学键力等强吸附力的作用。ΔG<0,表明氯离子在大孔树脂上的吸附过程能够自发地进行。不同氯离子初始浓度下ΔG变化在-3～-5kJ·mol-1范围内,说明该吸附过程为物理吸附。吸附熵变ΔS>0,表明在Cl-的吸附过程中同时存在着溶剂的解吸,ΔS变化范围为0.004～0.1kJ·mol-1。

In this paper, the thermodynamic characteristics of the adsorption of chlorine ions by H-103 macro-porous resin were studied.The results showed that the H-103 resin adsorption of chloride ion in the waste water in accordance with the Freundlieh isothermal adsorption equation, the Freundlich equation fitting Kf value under dif-ferent temperature change is not big, shows that the effect of temperature is very small, the Freundlich equation parameters of n is greater than 1, show that H-103 resin adsorption chlorine ion belongs to the preferential adsorp- tion;Adsorption enthalpy change △H〈O, it shows that chloride ion adsorption on H-103 resin as the exothermie process; but △H〈5kJ·mol^-1, enthalpy change value is small, show that the influence of temperature on the adsorp-tion process is not obvious, it also shows that the chloride ion on H-103 resin adsorption was not found on the lig-and exchange and chemical bonding force. △G〈0 indicates that the adsorption process of chlorine ion on macrop-orous resin can be carried out automatically. AG under the different initial concentration of chloride ion is among - 3^-5kJ·mo1^-1 range, therefore, the adsorption process can be spontaneous. Adsorption entropy change △S〉0, indi-cates that there is solvent desorption in the process and adsorption entropy change AS changed range of 0.004 ~ 0.1 kJ·mol^-1.