聚吡咯/壳聚糖复合膜的制备及其对Cu(Ⅱ)和Cr(Ⅵ)吸附机制  

Preparation of polypyrrole/chitosan composite membrane and its adsorption mechanism for Cu(Ⅱ)and Cr(Ⅵ)

作　　者：狄婧 刘海霞 姜永强 郭金鑫 赵国虎 DI Jing;LIU Haixia;JIANG Yongqiang;GUO Jinxin;ZHAO Guohu(School of Chemical and Biological Engineering,Lanzhou Jiaotong University,Lanzhou 730070,China;School of Chemistry and Chemical Engineering,Provincial Key Laboratory of Gansu Higher Education for City Environmental Pollution Control,Lanzhou City University,Lanzhou 730070,China)

机构地区：[1]兰州交通大学化学与生物工程学院,兰州730070 [2]兰州城市学院化学化工学院"城市环境污染控制"甘肃省高校省级重点实验室,兰州730070

出　　处：《复合材料学报》2021年第1期221-231,共11页Acta Materiae Compositae Sinica

基　　金：“生态环境相关高分子材料教育部重点实验室”开放基金(KF-18-04);甘肃省自然科学基金(18JR3RA220)。

摘　　要：以聚吡咯(PPy)和壳聚糖(CS)为原料,制备PPy/CS复合膜,通过红外、孔径分析、热分析和SEM等手段对其结构进行表征,并研究了PPy/CS复合膜对Cu(Ⅱ)和Cr(Ⅵ)吸附性能的影响及吸附机制,考察了pH值、吸附时间、溶液起始浓度等因素对吸附率的影响。结果表明,初始浓度对吸附率影响最大;在pH=3.5、温度为333 K及速率为100 r·min^(-1)下震荡吸附50 min,20 mg的PPy/CS复合膜吸附6 mg·L^(-1)的Cu(Ⅱ)和Cr(Ⅵ)混合液时,PPy/CS复合膜对Cu(Ⅱ)表现出很好的选择性,吸附量达2.715 mg·g^(-1);通过对PPy/CS复合膜和CS膜的吸附性能比较,PPy/CS复合膜对Cu(Ⅱ)的吸附率增加至94.14%;采用0.1 mol·L^(-1)的NaOH溶液对吸附Cu(Ⅱ)和Cr(Ⅵ)的PPy/CS复合膜进行脱附再生,循环15次后,其吸附量变化很小,可以多次使用。研究表明,PPy/CS复合膜对Cu(Ⅱ)和Cr(Ⅵ)的吸附符合准二级动力学模型和Langmuir吸附等温式。A polypyrrole/chitosan(PPy/CS)composite membrane was prepared using PPy and CS as raw materials,and the structure of the PPy/CS composite membrane was characterized by infrared,pore diameter analysis,thermal analysis and SEM.The effects of PPy/CS composite membrane on the adsorption performance and adsorption mechanism for Cu(Ⅱ)and Cr(Ⅵ)were discussed.The effects of pH value,adsorption time,and initial concentration of the solution on the adsorption efficiency were investigated.The results show that the adsorption efficiency of PPy/CS composite membrane for Cu(Ⅱ)and Cr(Ⅵ)are greater affected by the initial concentration of the solution.When pH=3.5,temperature is 333 K,the adsorption is shaken at 100 r·min^(-1)for 50 min,20 mg of PPy/CS composite membrane adsorbs 6 mg·L^(-1)of Cu(Ⅱ)and Cr(Ⅵ),PPy/CS composite membrane for Cu(Ⅱ)shows good selectivity and adsorption amount reaches 2.715 mg·g^(-1);Compared with PPy/CS composite membrane and CS membrane,the adsorption rate of PPy/CS composite membrane for Cu(Ⅱ)increases to 94.14%;The PPy/CS composite membrane adsorbing Cu(Ⅱ)and Cr(Ⅵ)is desorbed and regenerated with 0.1 mol·L^(-1)NaOH solution.After circulation for 15 times,its adsorption amount changes very small,it can be used multiple times.The adsorption of Cu(Ⅱ)and Cr(Ⅵ)by PPy/CS composite membrane conforms to the pseudo-second-order kinetic model and Langmuir adsorption isotherm.

关 键 词：聚吡咯 壳聚糖 复合膜 吸附 Cu(Ⅱ) Cr(Ⅵ) 

分 类 号：TB332[一般工业技术—材料科学与工程]