欢迎访问过程工程学报, 今天是

›› 2012, Vol. 12 ›› Issue (1): 24-30.

• 反应与分离 • 上一篇    下一篇

2,4-二羟基苯甲酸在3种树脂上的吸附特性

谢祖芳 刘国超 童张法   

  1. 玉林师范学院化学与材料学院 广西大学化学化工学院 广西大学化学化工学院
  • 收稿日期:2012-01-12 修回日期:2012-02-13 出版日期:2012-02-20 发布日期:2012-02-20
  • 通讯作者: 谢祖芳

Adsorption Properties of 2,4-Dihydroxybenzoic Acid on Three Anion Exchange Resins

XIE Zu-fang LIU Guo-chao TONG Zhang-fa   

  1. School of Chemistry and Materials, Yulin Teachers' College School of Chemistry and Chemical Engineering, Guangxi University School of Chemistry and Chemical Engineering,Guangxi University,Nanning
  • Received:2012-01-12 Revised:2012-02-13 Online:2012-02-20 Published:2012-02-20
  • Contact: XIE Zu-fang

摘要: 通过静态和动态吸附实验, 研究了717(凝胶型,强碱)、D201(大孔型,强碱)和D301R(大孔型,弱碱)3种阴离子交换树脂对水溶液中2,4-二羟基苯甲酸的吸附特性. 结果表明,717和D201在pH 4~11时、D301R在pH 3~9时吸附能力最好. 在pH=5及温度293~313 K、初始浓度0.6488~6.488 mmol/L条件下,D301R, 717和D201对2,4-二羟基苯甲酸的等温吸附规律均符合Freundlich模型,最大平衡吸附量分别为2.98, 2.66和2.54 mmol/g(吸附未达饱和),均为物理性自发吸附的放热过程. 动力学实验数据用准一级模型方程拟合比准二级更接近实验值. 5%(w) NaCl+2%(w) NaOH脱附液100 mL均可有效洗脱3种树脂上吸附的2,4-二羟基苯甲酸,脱附率达99%. 相同条件下,D301R树脂对2,4-二羟基苯甲酸的吸附性能优于D201和717树脂.

关键词: 4-二羟基苯甲酸, 阴离子交换树脂, 吸附, 热力学, 动力学

Abstract: The adsorption properties of 2,4-dihydroxybenzoic acid by 717 (gel-type, strong base), D201 (macroporous-type, strong base) and D301R (macroporous-type, weak base) resins were studied through static and dynamic experiments. The results show that the maximum adsorption ability of 717 and D201 resins occurs at pH=4~11, and D301R resin at pH=3~9. At pH=5, 293~313 K and initial concentration of 2,4-dihydroxybenzoic acid of 0.6488~6.488 mmol/L, the adsorption isotherms of 2,4-dihydroxybenzoic acid on D301R, 717 and D201 resins obey Freundlich model, and their maximum equilibrium adsorption capacity is 2.98, 2.66 and 2.54 mmol/g, respectively (the adsorption has not reached saturation yet). The adsorptions are physical and spontaneous, exothermal processes. Pseudo first-order and pseudo second-order models were applied to correlate the kinetic experimental data. The former was more accordant with the experimental data than the latter. The 2,4-dihydroxybenzoic acid adsorbed on the three resins could be eluted by 100 mL 5%(w) NaCl+2%(w) NaOH solution quickly with elution rate reaching 99%. The adsorption performance of 2,4-dihydroxybenzoic acid on D301R resin was better than on that on D201 and 717 resins under the same conditions.

Key words: 4-dihydroxybenzoic acid, anion exchange resin, adsorption, thermodynamics, kinetics

中图分类号: