化工学报 ›› 2008, Vol. 59 ›› Issue (6): 1535-1540.

• 能源和环境工程 • 上一篇    下一篇

有机皂土的双硫腙修饰及其对水中铅离子的吸附行为

张东;任广军;徐亮子   

  1. 沈阳理工大学环境与化学工程学院
  • 出版日期:2008-06-05 发布日期:2008-06-05

Modification of organobentonite with dithizone and its adsorption behavior for lead ion in water

ZHANG Dong;REN Guangjun;XU Liangzi   

  • Online:2008-06-05 Published:2008-06-05

摘要: 采用十六烷基三甲基溴化铵(CTMAB)对皂土进行改性,用双硫腙对其表面进行修饰,制备了廉价的新型固态吸附剂。用傅立叶变换红外光谱进行了表征。以火焰原子吸收为检测手段,研究了该吸附剂对水中铅离子的吸附行为,计算了吸附过程的焓变(△H),吉布斯自由能变(△G)和熵变(△S)等热力学常数和吸附活化能。结果表明,用CTMAB改性后,双硫腙可牢固的负载于皂土上,制备的固态吸附剂对水中铅离子具有较强的吸附能力。吸附量受介质的pH值,温度和吸附时间的影响。其吸附行为符合Langmuir吸附等温模型和HO准二级动力学方程式。该吸附反应为自发的吸热过程。

关键词:

有机皂土, 双硫腙, 修饰, 铅, 吸附行为, 火焰原子吸收光谱法

Abstract:

The adsorption behavior of the organobentonite (CTMAB-bentonite) modified with dithizone for lead ion in water was investigated.A sort of cheap sorbent was prepared through modifying organobentonite with dithizone and was characterized with FT-IR.By means of flame atomic absorption spectrometry (FAAS), the adsorption situation and mechanism were studied.The results showed that after treating bentonite with cetyl trimethyl ammonium bromide (CTMAB),dithizone could be immobilized on the bentonite firmly.The lead ion in water could be adsorbed quantitatively on the organobentonite modified with dithizone, and the adsorbed quantity was affected by pH value of medium, temperature and time.The adsorption behavior followed a Langmuir adsorption isotherm and a pseudo-second-order kinetic model.The enthalpy change of the adsorption process was 58.432 kJ·mol-1,and Gibbs free energy change was negative at different temperatures.The reaction of adsorption was an spontaneous, endothermal process.

Key words:

有机皂土, 双硫腙, 修饰, 铅, 吸附行为, 火焰原子吸收光谱法