多壁碳纳米管对水中腐殖酸的吸附行为研究

以多壁碳纳米管为吸附剂对水中腐殖酸（HA）的吸附行为进行了研究,重点考察了各种因素下碳纳米管对腐殖酸吸附效果的影响,如吸附温度、吸附时间、溶液pH、共存离子等.实验结果表明,在15℃,25℃和35℃条件下,多壁碳纳米管对腐殖酸的吸附等温线可以用Freundlich模型模拟,其实验条件下的最大吸附量分别为37.77mg/g,41.89mg/g,52.95mg/g;吸附剂对水中腐殖酸的吸附在12h内可达平衡,且吸附动力学符合拟二级动力学方程;碳纳米管对腐殖酸的吸附量随溶液pH的增加而降低;水中金属阳离子的存在能促进腐殖酸的吸附,不同类型的阳离子对腐殖酸吸附效果影响的大小顺序为：Ca2＋﹥K＋﹥Na＋.

Adsorption behavior of aqueous humic acid on mult-walled carbon nanotube

In this study,mult-walled carbon nanotube(MWNT) was used as an adsorbent to remove humic acid(HA) from aqueous environment.Factors affecting the adsorption amount of HA on MWNT were mainly investigated,including adsorption temperature,adsorption time,solution pH values and co-existing ionic.As the results,adsorption isotherm of HA on MWCT can be fitted by Freundlich equation.In tested condition,the maximum adsorption amount of HA was 37.77mg/g,41.89mg/g,52.95mg/g at 15 ℃,25 ℃ and 35℃;The adsorption equilibrium can be acheived within 12 h,and the adsorption kinetics were fitted by the pseudo-second order kinetics model very well;Humic acid adsorption amount onto adsorbent decreased with the increasing of solution pH;The effect of different metal cations was in the order of Ca2+﹥K+﹥Na+.