纳米纤维素气凝胶的制备及其重金属离子吸附性能  

Preparation of Cellulose Nanofiber Aerogel and Its Adsorption Properties for Heavy Metal Ions

作　　者：李楠[1] 张文静 李圆圆 代红艳[1] LI Nan;ZHANG Wenjing;LI Yuanyuan;DAI Hongyan(Department of Architecture and Enviromental Engineering,Taiyuan University,Shanxi,Taiyuan 030032,China)

机构地区：[1]太原学院建筑与环境工程系,山西太原030032

出　　处：《山西大学学报（自然科学版）》2024年第6期1268-1276,共9页Journal of Shanxi University(Natural Science Edition)

基　　金：山西省高等学校科技创新项目(2023L384);太原学院教学改革项目(jg202219)。

摘　　要：针对水中重金属离子的污染问题,本文利用冰模板诱导的快速冷冻干燥和造孔技术,制备了具有丰富孔道结构的2,2,6,6-四甲基哌啶氧化物(2,2,6,6-tetramethylpiperidine oxide,TEMPO)氧化纳米纤维素(nano-crystalline cellulose,TOCNF)/聚丙烯酸(Poly acrylic acid,PAA)复合气凝胶(composite aerogel,TP复合气凝胶)。探究了TOCNF和PAA的配比对复合气凝胶形貌和结构的影响,当TOCNF∶PAA=6∶4(TP-6)时,TP-6复合气凝胶展现出完整互联的孔结构和最大的比表面积(246.7 m^(2)/g)。TP-6复合气凝胶中丰富的孔结构和其中大量的羧基和羟基赋予了其优秀的重金属离子吸附特性,在pH为1.0~6.5的范围内,TP-6复合气凝胶对重金属离子的吸附能力随pH增加逐步增强。在pH为6.5时,TP-6复合气凝胶对Cu^(2+)、Pb^(2+)和Cd^(2+)的最大吸附量分别为115.2 mg/g、136.1 mg/g、137.2 mg/g。本文提出的冰模板诱导的快速冷冻干燥和造孔技术为废水中重金属离子的绿色、高效去除提供了参考思路。To address the issue of heavy metal ion contamination in water,we synthesized a TEMPO(2,2,6,6-Tetramethylpiperidinooxy)-oxidized nanocellulose(TOCNF)/polyacrylic acid(PAA)composite aerogel(TP composite aerogel)featuring a highly porous structure.This aerogel was produced using ice-templating and rapid freeze-drying techniques to enhance pore formation.The influence of the ratio of TOCNF to PAA on the morphology and structure of the composite aerogel was examined.As a result,when the ratio of TOCNF to PAA was 6∶4(TP-6),the TP-6 composite aerogel exhibited a interconnected pore structure and achieved a maximum specific surface area of 246.7 m^(2)/g.The abundant pore structure and numerous carboxyl and hydroxyl groups in the TP-6 composite aerogel confer excellent heavy metal ion adsorption properties.Within a pH range of 1.0 to 6.5,the adsorption capacity of the TP-6 composite aerogel for heavy metal ions increases progressively with pH rising.At a pH of 6.5,the TP-6 composite aerogel demonstrated maximum adsorption capacities for Cu^(2+),Pb^(2+),and Cd^(2+),of 115.2 mg/g,136.1 mg/g,and 137.2 mg/g,respectively.The ice-templated rapid freeze-drying technique offers a novel approach for the green and efficient removal of heavy metal ions from wastewater.

关 键 词：TEMPO氧化纳米纤维素 定向冷冻干燥 生物质气凝胶 可再生材料 

分 类 号：O436[机械工程—光学工程]