羟基铁柱撑膨润土吸附剂去除水中甲基橙的研究

Removal of Methyl Orange from Aqueous Solution Using Fe-pillared-montmorillonites

以硝酸铁为原料制备柱化剂,对钙基膨润土进行柱撑改性,制备了羟基铁柱撑膨润土吸附剂.利用扫描电子显微镜(SEM)对铁柱撑膨润土进行了表征.实验研究其对模拟废水中甲基橙的吸附性能和影响因素,分析其在不同温度下的吸附等温线及其对甲基橙的吸附动力学,结果表明:柱撑后羟基铁能够进入到膨润土的层间,且羟基铁柱撑膨润土对甲基橙有更好的吸附效果.在常温、吸附剂用量1.2g/L、溶液pH=7、吸附时间20 min、甲基橙质量浓度25 mg/L的条件下,吸附剂对甲基橙的去除率可达84%以上.Langmuir等温吸附方程能较好地描述羟基铁柱撑膨润土对甲基橙的吸附平衡,其吸附动力学符合准二级动力学方程.

A series of Fe-pillared bentonite adsorbents have been successfully prepared by pillaring calcium-base-bentonite using pillaring agent prepared from ferric nitrate.The Fe-pillared bentonite was characterized by using scanning electron microscopy(SEM).The adsorption performance of the samples has been studied by adsorption of methyl orange in water.The influential factors such as adsorbent dosage,time,temperature and solution pH on the removal of methyl orange were investigated.The results showed that Fe-pillared bentonite exhibited higher adsorption performance than pure bentonite,the removal rate of methyl orange could be over 84%under the conditions of adsorbent dosage 1.2 g/L,pH = 7.0,adsorption time 20 min and concentration of methyl orange 25 mg/L.The adsorption isotherm of methyl orange on Fe-pillared bentonite could be described well by Langmuir equation.The adsorption kinetic data could be described by the pseudo-second-order kinetic equation.