Removal of malathion and butachlor from aqueous solution by clays and organoclays
Removal of malathion and butachlor from aqueous solution by clays and organoclays
复制标题
用粘土和有机粘土去除水溶液中的马拉硫磷和丁草胺
DOI：
10.1016/s1383-5866(00)00226-4
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发表时间：
2001
期刊：
影响因子：
--
通讯作者：
A. K. Vanjara
中科院分区：
文献类型：
--
作者：
O. R. Pal;A. K. Vanjara
研究了高岭土、蒙脱石、膨润土和有机粘土对马拉硫磷和丁草胺的吸附。通过季铵盐型表面活性剂十四烷基三甲基溴化铵(TTAB)、十二烷基三甲基溴化铵(DTAB)和十六烷基氯化吡啶(CPC)与粘土内外表面的Na+、Ca~(2+)等无机阳离子的交换，制备了有机粘土。这种改性使粘土的表面性质由亲水变为疏水。吸附平衡数据符合Freundlich等温方程。粘土经表面活性剂处理后，对马拉硫磷和丁草胺的吸附作用显著增强。单位质量有机粘土对这两种农药的吸附量遵循TTA-kaolin<；TTA-montmorillonite<；TTA-bentonite，的顺序，这与粘土的有机碳含量不一致。有机蒙脱土对马拉硫磷的去除效率为CP(C16)-montmorillonite>；TTA(C14)-montmorillonite>；DTA(C12)-montmorillonite.量级丁草胺在各吸附剂上的吸附程度大于马拉硫磷，这可能是由于丁草胺具有较高的疏水性，表明吸附/吸附体系之间存在较强的疏水相互作用。这些发现可能会在从含水层中清除稀有的水溶性农药方面得到应用。
Adsorption of malathion and butachlor onto kaolin, montmorillonite, bentonite clays and respective organoclays were studied. Organoclays were prepared by the exchange of quaternary ammonium type surfactants such as tetradecyltrimethyl ammonium bromide (TTAB), dodecyltrimethylammonium bromide (DTAB), and cetylpyridinium chloride (CPC) for inorganic cations like Na+and Ca2+on internal and external surface of the clays. This modification produces a change of surface property of clay from hydrophilic to hydrophobic. The adsorption equilibrium data points were fitted to Freundlich isotherm equations. The adsorption of malathion and butachlor were significantly enhanced by surfactant treatment of the clays. The amount of both pesticides adsorbed per unit mass of organoclay followed the order of TTA-kaolin<TTA-montmorillonite<TTA-bentonite, which is inconsistent with the organic carbon content of the clays. The removal efficiency of organomontmorillonite to treat malathion is in the order of CP(C16)-montmorillonite>TTA(C14)-montmorillonite>DTA(C12)-montmorillonite. Butachlor is adsorbed to greater extent than malathion by each adsorbent, which may be due to the higher hydrophobicity of butachlor, indicating considerable hydrophobic interaction between adsorbent/adsorbate system. These findings may find applications in the removal of sparingly water soluble pesticides from aquifers.