戊二醛/壳聚糖交联复合材料的制备及其对3种染料的吸附性能及其机理

Preparation of glutaraldehyde/chitosan cross-linked composite material and study on its adsorption properties and mechanism for three dyes

【目的】研究戊二醛/壳聚糖交联复合材料(G/CS)对不同染料的吸附性能和吸附机理.【方法】采用流延法制备了G/CS,采用SEM、TG和FT-IR对G/CS结构进行表征,运用正交试验考察影响吸附的因素并利用吸附模型对染料的吸附机理进行研究.【结果】G/CS被成功合成且含有大量活性位点,最优吸附条件下,酸性品红(AF)去除率为95.83%,碱性品红(FB)去除率为71.53%,甲基橙(MO)去除率为89.70%,三者吸附过程都符合准二级动力学模型(R^2>0.99)和Langmuir吸附等温模型,G/CS吸附AF、MO属于吸热自发过程,吸附FB属于放热非自发过程.【结论】研究表明,G/CS可循环再生应用5次以上,去除率基本保持不变,是一种性能良好的染料吸附剂材料,为染料废水处理提供了新途径.

【Objective】To study the adsorption properties and adsorption mechanism of glutaraldehyde/chitosan cross-linked composite material(G/CS)for different dyes.【Method】G/CS membrane was prepared by casting method.The structure of G/CS membrane was characterized by SEM,TG and FT-IR.The factors affecting adsorption were explored by using orthogonal experiment and the adsorption mechanism was studied by using the adsorption model.【Result】G/CS membrane was successfully synthesized and contained a large number of active sites.Under the optimal adsorption conditions,the removal rate of acid magenta(AF),alkaline magenta(FB)and methyl orange(MO)was 95.83%,71.53%and 89.70%respectively.All three adsorption processes fitted the quasi-second-order kinetic model(R^2>0.99)and Langmuir adsorption isotherm model.The process that G/CS adsorbing AF and MO belonged to endothermic spontaneous process,and that adsorbing FB belonged to exothermic non-spontaneous process.【Conclusion】The G/CS membrane can be recycled and reused more than 5 times,the removal rate is stable.It is a dye adsorbent material with good performance and provides a new way for dye wastewater treatment.