金属改性蛭石基多孔材料的制备及吸附染料性能研究

Preparation of Metal Modified Porous Materials Based on Vermiculite and Their Enhanced Dye Adsorption Performances

采用酸处理、钠化、十六烷基三甲基溴化铵插层和金属硝酸盐浸渍等手段依次对蛭石进行一系列改性,制备了金属(La、Ce和Zr)改性的蛭石基多孔材料。并采用XRD及BET测试对样品进行表征,结果表明,金属离子改性后吸附剂的比表面比原蛭石增大了33倍,孔容增大了3个数量级。在相同条件下,La改性蛭石基多孔材料(La-蛭石)对亚甲基蓝(MB)的去除率最大。以La-蛭石为吸附剂,研究了其对MB的吸附动力学,并采用假二级动力学模型进行拟合。此外,分别研究了温度和p H值对吸附的影响。在所研究温度范围10-60℃,La-蛭石对MB的去除率随温度升高而增大;p H在5-9之间时,La-蛭石对MB的吸附效果较好。

Metal modified porous materials based on vermiculite are prepared by treating with nitric acid, sodium chloride, cetyltrimethylammonium bromide and metal（La, Ce and Zr） nitrate respectively. The synthesized samples are characterized by XRD and BET analysis. The results show that the BET values of modified samples are33 times larger than raw vermiculite, while the pore volumes are enlarged 1000 times. Among the three prepared samples, La modified porous materials based on vermiculite displayed the highest removal（%） of methylene blue（MB）. The adsorption kinetics is investigated and the adsorption data are modeled by pseudo-second order equation. The effects of temperature and p H values on the removal（%） of MB are also studied. The removal（%） of MB increases with the increasing temperature from 10℃ to 60℃, while high removal（%） is observed in p H range of 5.0-9.0.