改性蒙脱土吸附2,4-二氯-5-硝基苯酚的研究

Study on adsorption of 2,4-dichloro-5-nitrophenol by modified montmorillonites

分别采用新型双子阳离子表面活性剂Y-16和十六烷基三甲基溴化铵(CTAB)改性钠基蒙脱土,通过IR、TGA、XRD对其进行表征,研究了表面活性剂的浓度、改性蒙脱土的用量以及接触时间对2,4-二氯-5-硝基苯酚(DCNP)吸附的影响。结果表明:上述两种表面活性剂成功插入钠基蒙脱土层间结构且扩大了其层间距。随着表面活性剂的浓度、改性蒙脱土的用量、接触时间的增加,改性蒙脱土对DCNP的吸附量也随之增加,并达到最大值。当采用0.1g 1.8CEC改性蒙脱土且接触时间为180min时,CTAB-MMT和Y-16-MMT对DCNP达到最大吸附量分别为184.84mg·g^(-1)、164.47mg·g^(-1)。改性蒙脱土对DCNP的吸附行为符合二级动力学方程和Langmuir等温吸附方程。

The sodium-based montmorillonite modified respectively with the novel gemini cationic surfactant Y-16 and cetyltrimethylammonium bromide(CTAB)were characterized by IR,TGA and XRD.The effects of surfactant concentration,amount of modified montmorillonite and contact time on the adsorption of 2,4-dichloro-5-nitrophenol(DCNP)were studied.The results showed that both two surfactants above were successfully inserted into sodium montmorillonite interlayer structure,expanding the spacing of its layers.With the increase of surfactant concentration,amount of modified montmorillonite and contact time,the adsorption capacity of DCNP on modified montmorillonite also increased.The optimum conditions for CTAB-MMT and Y-16-MMT were as follows:1.8 CEC of the concentration of surfactants,0.1 g the modified montmorillonite and contact time of 180 min,the maximum adsorption capacity of CTAB-MMT and Y-16-MMT reached to 184.84 mg·g-1 and 164.47 mg·g-1,respectively.The adsorption behavior of modified montmorillonite on DCNP was in accordance with the second-order kinetics equation and the Langmuir isothermal adsorption equation.