季铵盐表面活性剂有机蒙脱土的制备及其苯酚吸附行为研究

选用阳离子表面活性剂双十六烷基二甲基溴化铵(DHDMA)和Gemini型表面活性剂1,2-亚乙基-双(十六烷基二甲基溴化铵)(16-2-16)分别制备2种有机蒙脱土产品DHDMA-MMT和16-2-16-MMT。采用FT-IR,XRD和TGA进行产品结构表征;并对比研究了2种产品吸附水中苯酚的性能。实验结果表明,当表面活性剂负载量相当时,2种产品有机碳含量相近,而16-2-16-MMT对苯酚的吸附量和有机碳归一化吸附系数均显著大于DHDMA-MMT。2种产品的分子中均含有2条十六烷基碳链,16-2-16分子仅比DHDMA分子多1个季铵盐头基,表明季铵盐头基在有机蒙脱土吸附苯酚过程中具有重要的作用。

Preparation of organo-montmorillonite modified with quaternary ammonium surfactant and its adsorption behavior for phenol

Cationic surfactant dihexadecyldimethyl ammonium bromide (DHDMA) and Gemini surfactant 1,2-ethylene bis(cetyldimethyl ammonium bromide) (16-2-16) were used separately to prepare two kinds of organo-montmorillonite DHDMA-MMT and 16-2-16-MMT. The products were characterized by FT-IR, X-ray diffraction and thermal gravimetric analysis (TGA). Phenol adsorption behavior of the two kinds of product was investigated and compared. Experiment results demonstrated that the organic carbon content of the two kinds of product is close to each other at the same surfactant loadings while the adsorption amount of phenol and normalized organic carbon content adsorption coefficient of 16-2-16-MMT is remarkably higher than that of DHDMA-MMT. In view of that same carbon chains are containing in the molecule structure of the two kinds of product, and the structure difference of the two surfactants is only that 16-2-16 owns an extra quaternary ammonium headgroup as comparing with DHDMA, it is reasonable to conclude that the quaternary ammonium headgroup plays an important role in the process of adsorbing phenol from aqueous solution by the organo-montmorillonite.