氨基改性埃洛石纳米管对痕量孔雀石绿的吸附研究

摘要

为了提高吸附剂对水中孔雀石绿(MG)的去除效果,对埃洛石纳米管改性,制备了氨基功能化的埃洛石纳米管.将该材料用于水中MG的吸附,研究了溶液pH值、温度、吸附时间等因素对MG去除率的影响,考察了吸附机理、吸附选择性和吸附剂的循环使用性能.结果表明,在pH为4~10范围内材料对MG有较好的吸附性能,吸附量随温度的增加而增大;在最佳条件下,材料可去除水中浓度低至0.01 mg·L-1的MG,最大吸附量高达48.40 mg·g-1,比改性前提高了101.73%;吸附过程主要是静电吸附,可通过溶液pH的改变调控吸附选择性,吸附剂可再生重复使用.将该方法用于5种实际水样中MG的吸附,去除率在97.14~99.04%之间.%In order to increase the removal efficiency of Mallachite Green(MG)by adsorbents from water,the halloysite nanotubes modified by amino group was prepared and applied for the removal of MG. The effect of pH values,system temperature and adsorp-tion time on the removal efficiency of MG were studied. In addition,the adsorption mechanism and selectivity as well as recyclinguti-lization of the materials were investigated. The results showed that the as-prepared materials displayed excellent adsorption efficiency for the MG at the pH range of 4~10,and the adsorption capacity increased with the increase of temperature. Under the optimal con-ditions,the materials could remove the MG with the contention as low as 0. 01 mg . g-1 ,and the maximum adsorption capacity of NH2-HNTs reached 48. 40 mg . g-1 ,which increased by 101. 73% as compared with that of the unmodified HNTs. The adsorption process mainly was static interaction,and the selectivity could be easily regulated by changing the pH value of the solution. Moreo-ver,the material could be recycled. Satisfactory results could also be obtained for the removal of MG in real water samples and the recoveries were in the range of 97. 14~99. 04%.