接枝亲水型高分子的丝瓜络对水中重金属离子的吸附行为

摘要

A kind of partially hydrolyzed polyacrylamidehydrophilic luffa sponges [luffa-g-(PAM-co-PAANa)] was prepared through grafting polymerization, and the grafting percentage reached up to 161.3%.In typical Cu2+ and Pb2+ systems, the adsorption behavior of hydrophilic luffa sponges was studied.In a single metal ion system, the adsorption kinetics fits well with the pseudo-second-order kinetic equation.The adsorption capacities increase with the grafting percentage and pH value.In particular, the highest adsorption capacities can reach up to 647 mg/g for Cu2+ and 887 mg/g for Pb2+.Hydrophilic sample can be regenerated through a simple route and reused in eight adsorption-desorption cycles without any significant loss in the adsorption capacity.The adsorption mechanism was discussed.Definitely, this kind of hydrophilic luffa sponges as effective adsorbent, exhibits potential application in the purification of polluted water system.%采用接枝聚合的方法将亲水性聚丙烯酰胺接枝到丝瓜络上,部分水解的聚丙烯酰胺的接枝率可高达161.3%.选择典型的Cu.2+和Pb.2+体系,研究亲水型丝瓜络对水中重金属离子的吸附行为.结果表明,在单离子体系中,准二级动力学方程适于描述亲水型丝瓜络吸附动力学过程,饱和吸附量随着接枝率和pH值增加而增大,对Cu2+和Pb2+的最大饱和吸附量分别为647和 887 mg/g.Langmuir 和Freundlich等温吸附模型都适合描述等温吸附过程.8次吸附-解吸附循环实验表明,饱和吸附量基本保持恒定,同时对吸附机理进行了讨论.