针对传统吸附剂与水相分离困难的问题,设计并制备了一种环境友好、成本低廉的壳聚糖复合材料ZIF-67/CS。针对吸附剂对孔雀石绿(MG)污染物的吸附性能,考察了污染物浓度、接触时间、吸附剂用量、pH和离子强度对其吸附性能的影响。利用XRD、SEM、FT-IR、TG等对其结构、形貌及热稳定性进行了表征。结果表明,在吸附实验中,303.15 K时ZIF-67/CS对MG的吸附等温线符合Temkin等温吸附模型;吸附动力学拟合结果表明,ZIF-67/CS对MG的吸附行为符合拟二级吸附动力学模型;吸附热力学结果表明吸附过程是自发的、吸热的。ZIF-67/CS对MG的吸附是一个复杂的化学吸附过程,主要由速率决定。

ZIF-67/CS,an environmentally friendly low-cost chitosan-based composite,is designed and prepared in order to solve the problem that traditional adsorbents are difficult to separate from water phase.The impacts of pollutant concentration,contact time,adsorbent dosage,pH and ionic strength on the adsorption performance of ZIF-67/CS adsorbent for malachite green pollutants are investigated.The structure,morphology and thermal stability of ZIF-67/CS adsorbent are characterized by means of XRD,SEM,FT-IR and TG.It is shown that in the adsorption experiment,the adsorption isotherm of malachite green by ZIF-67/CS at 303.15 K conforms to the Temkin isothermal adsorption model.It is indicated by the adsorption kinetic fitting results that the adsorption behavior of malachite green by ZIF-67/CS conforms to the pseudo second-order adsorption kinetic model.It is verified from adsorption thermodynamics results that the adsorption process is spontaneous and heat-absorbing.Therefore,the adsorption of malachite green by ZIF-67/CS is a complex chemical adsorption process,which is mainly determined by the speed.