十二烷基苯磺酸钠对磁性多壁碳纳米管吸附水中重金属离子的影响  

Influence of Sodium Dodecyl Benzene Sulfonate on Magnetic Multi-walled Carbon Nanotubes’ Adsorbing Heavy Metal Ions in Aqueous Solutions

作　　者：吴娜[1,2] 熊振湖[1,2] 

机构地区：[1]天津城市建设学院天津市水质科学与技术重点实验室,天津300384 [2]天津城市建设学院环境与市政工程学院,天津300384

出　　处：《天津城市建设学院学报》2012年第3期192-198,共7页Journal of Tianjin Institute of Urban Construction

基　　金：国家自然科学基金(50878138)

摘　　要：通过水溶液中磁性多壁碳纳米管(MWCNTs)对Cd(II)、Zn(II)、Cu(II)三种重金属离子的吸附实验,探讨了十二烷基苯磺酸钠(SDBS)表面活性剂的添加量对吸附效率的促进与抑制效应,以及溶液pH值和碱金属离子强度对磁性MWCNTs吸附重金属离子的影响.实验结果表明:溶液的酸性或强碱性对磁性MWCNTs吸附重金属离子有较强的负面影响;而溶液呈中性偏碱性时(pH值在7～10)吸附效果较好,其最大值达90%以上;水中存在SDBS时,磁性MWCNTs吸附重金属离子的效果受溶液酸碱性的影响很小,但SDBS剂量较大时,吸附效果则会受影响;添加Na+、K+改变水溶液中的离子强度,吸附效果几乎不受影响.吸附动力学研究发现,准二级方程能够真实地拟合重金属离子在磁性MWCNTs上的吸附过程.Through the adsorption experiments of magnetic MWCNTs in aqueous solution adsorbing three kinds of heavy metal ions, which were Cd （II）, Zn （II） and Cu （II）, we explored the promotion and inhibition effects of the amount of sodium dodecyl benzene sulfonate （SDBS） surfactant on the adsorption efficiency, as well as the influence ofpH and ionic strength of alkali metal on magnetic MWCNTs adsorbing heavy metal ions. The results show that the acidity or alkalinity of the solution will have a strong negative impact on the magnetic MWCNTs＇ adsorption of metal ions; while the solution which is neutral and slightly alkaline （pH = 7-10）, the adsorption efficiency is better than that in acid or alkali solutions, with the maximum of more than 90%. In the presence of SDBS, the effect of solution pH on adsorbing of heavy metal ions by magnetic MWCNTs is very small; while it was obviously affected if the dose of SDBS is large. Addition of Na＋ and K＋ will change the ionic strength of the solution; but the adsorption efficiency of the heavy metal ions is almost unaffected. The adsorption kinetics indicated that the pseudo-second equation could really fit the process of heavy metal ions adsorption on magnetic MWCNTs.

关 键 词：磁性多壁碳纳米管 重金属离子 表面活性剂 PH值 离子强度 

分 类 号：X52[环境科学与工程—环境工程]