物理化学学报 >> 2011, Vol. 27 >> Issue (06): 1474-1481.doi: 10.3866/PKU.WHXB20110529

催化和表面科学 上一篇    下一篇

亚氨二乙酸型复合材料IDAA-PGMA/SiO2对重金属及稀土离子的吸附行为与吸附热力学

姜桂明, 高保娇, 许文梅, 王晓华   

  1. 中北大学化学工程系, 太原 030051
  • 收稿日期:2010-12-31 修回日期:2011-02-03 发布日期:2011-05-31
  • 通讯作者: 高保娇 E-mail:gaobaojiao@126.com
  • 基金资助:

    山西省自然科学基金(201002100843)资助项目

Adsorption Behavior and Thermodynamics of Iminodiacetic Acid-Type Material IDAA-PGMA/SiO2 for Heavy Metal Ions and Rare Earth Ions

JIANG Gui-Ming, GAO Bao-Jiao, XU Wen-Mei, WANG Xiao-Hua   

  1. Department of Chemical Engineering, North University of China, Taiyuan 030051, P. R. China
  • Received:2010-12-31 Revised:2011-02-03 Published:2011-05-31
  • Contact: GAO Bao-Jiao E-mail:gaobaojiao@126.com
  • Supported by:

    The project was supported by the Natural Science Foundation of Shanxi Province, China (201002100843).

摘要:

将甲基丙烯酸缩水甘油酯(GMA)接枝于硅胶微粒表面,制得了接枝微粒PGMA/SiO2; 使亚氨二乙酸(IDAA)与接枝PGMA的环氧基团发生开环反应, 从而将亚氨二乙酸基团引入接枝微粒表面, 制得了复合螯合微粒材料IDAA-PGMA/SiO2. 本文研究了IDAA-PGMA/SiO2对重金属及稀土离子的螯合吸附行为, 深入地研究了吸附机理与吸附热力学. 研究结果表明: 凭借亚氨二乙酸基团与重金属离子之间的静电作用与配位螯合作用的协同, 复合微粒材料IDAA-PGMA/SiO2对重金属离子可产生强的螯合吸附作用, 尤其对Pb2+离子表现出很强的螯合吸附能力, 常温下吸附容量可达0.235 g·g-1; IDAA-PGMA/SiO2对重金属离子的吸附过程为一放热过程, 且为焓驱动的过程, 升高温度, 吸附容量降低; 对稀土离子的吸附过程则为熵驱动的过程; 在可抑制金属离子水解的pH范围内, 介质的pH值越高, IDAA-PGMA/SiO2的螯合吸附能力越强; IDAA-PGMA/SiO2对重金属离子的吸附容量远高于对稀土离子的吸附容量.

关键词: 亚氨二乙酸, 甲基丙烯酸缩水甘油酯, 螯合吸附, 重金属离子, 稀土离子

Abstract:

Glycidyl methacrylate (GMA) was grafted onto micron-sized silica gel particles and the grafted particles of PGMA/SiO2 were obtained. Subsequently, a ring-opening reaction of the epoxy groups on the grafted PGMA was carried out using iminodiacetic acid (IDAA) as a reagent, which resulted in IDAA group bonding and in the preparation of the composite chelating particles IDAA-PGMA/SiO2. In this work, the adsorption behavior and adsorption thermodynamics of IDAA-PGMA/SiO2 toward heavy metal ions and rare earth ions were investigated, and the adsorption mechanism was investigated in depth. The experimental results show that the particles IDAA-PGMA/SiO2 possess strong adsorption action for heavy metal ions and the adsorption capacity of the Pb2+ ions reached 0.235 g·g-1. The adsorption of heavy metal ions on IDAA-PGMA/SiO2 is exothermic and is driven by enthalpy, leading to a decrease in the adsorption capacity as temperature is raised. The adsorption of rare earth ions on IDAA-PGMA/SiO2 is driven by entropy. The adsorption ability of IDAA-PGMA/SiO2 toward heavy ions is much stronger than that toward the rare earth ions.

Key words: Iminodiacetic acid, Glycidyl methacrylate, Chelating action, Heavy metal ion, Rare earth ion