SCD-120阳离子交换树脂对镁离子的吸附及基础热力学性质

摘要

采用静态吸附法,研究了SCD-120阳离子交换树脂对镁离子的吸附,考察了氯化镁、溶液pH、温度、吸附时间对镁离子吸附量的影响,并对SCD-120树脂吸附镁离子的类型、速率及吸附过程的各热力学参数进行分析.结果表明,树脂用量5 g,氯化镁溶液浓度22.5％,吸附时间120 rain,pH值6.1,吸附温度60℃时,树脂对镁离子的吸附容量最佳,为2.71 mmol/g.吸附动力学及热力学分析表明,SCD-120树脂对镁离子的吸附为单分子层化学吸附,符合Langmuir型吸附,吸附反应速度是由液膜扩散和颗粒扩散等多个控制步骤决定,并且吸附的过程是一个吸热、自发的熵增过程.%The adsorption of magnesium ions by SCD-120 cation exchange resin was studied.The influence of MgCl2,solution pH,temperature and adsorption time etc on magnesium ion adsorption quantity were investigated.The adsorption type,adsorption rate and thermodynamic parameters of resin for magnesium ion was analyzed.The results showed that when adding the adsorbent dosage was 5 g,the concentration of MgC12 was 22.5 ％,the adsorption time was 120 min,adsorption temperature was 60 ℃,the pH was 6.1,the adsorption rate of the tea slag was best,which can reach 2.71 mmol/g.Based on the viewpoints of adsorption kinetics and thermodynamics.The adsorption of magnesium ions includes lots of mechanisms:The adsorption of magnesium on SCD-120 was chemical adsorption.The adsorption type was the type of Langmuir and the adsorption reaction rate was determined by the liquid film diffusion and particle diffusion.The adsorption was an endothermic and spontaneous entropy increase process.