琥珀酸改性天然竹纤维吸附镉/铅的行为机制  

Behaviors and mechanisms of cadmium/lead adsorption by natural bamboo fibers modified with succinic acid

作　　者：张晓峰 李相雨 王鑫 胡晶香 马振宇 谭峰亮 何璐 ZHANG Xiao-feng;LI Xiang-yu;WANG Xin;HU Jing-xiang;MA Zhen-yu;TAN Feng-liang;HE Lu(School of Materials and Environmental Engineering,Hunan University of Humanities and Technology,Loudi 417000;Key Laboratory of Fine Ceramics and Powder Materials in Hunan Province,Loudi 417000;Beijing Zhongnong Bohou Agricultural Science Research Institute,Beijing 100193)

机构地区：[1]湖南人文科技学院材料与环境工程学院,湖南娄底417000 [2]精细陶瓷与粉体材料湖南省重点实验室,湖南娄底417000 [3]北京中农博后农业科学研究院,北京100193

出　　处：《中国环境科学》2024年第8期4380-4388,共9页China Environmental Science

基　　金：国家自然科学基金资助项目(42207298);湖南省自然科学基金资助项目(2023JJ50087)。

摘　　要：天然竹纤维经碱化、酸化等预处理后,与琥珀酸发生行酯化连接反应,制得改性竹纤维.通过红外光谱(FTIR)与扫描电镜(SEM)分析可知,改性后竹纤维中电负性的羧基和酯基增加,其微观结构也由致密平整变为褶皱多孔.吸附实验结果表明,相较于天然竹纤维,其改性后对溶液中镉(Cd)、铅(Pb)的吸附率均明显提高(分别可达47.37%和44.57%以上),且能适用于更宽pH值范围.改性和未改性竹纤维对Cd和Pb的吸附反应既符合Langmuir热力学模型又符合Freundlich热力学模型.且由Langmuir等温方程计算可知,改性后的竹纤维对Cd和Pb的最大吸附容量(Q_(m))分别由8.9687mg/g和11.5075mg/g提高到26.1780mg/g和32.3625mg/g.这说明琥珀酸的改性过程增加了竹纤维吸附位点,从而提高了其对Cd/Pb的吸附能力,可为生物吸附材料的改性升级提供新思路.After pretreatments of alkalization and acidification,the natural bamboo fibers underwent esterification reaction with succinic acid to produce modified bamboo fibers.Infrared spectroscopy(FTIR)and scanning electron microscopy(SEM)analysis indicated that,after modification,the electronegative carboxyl and ester groups in bamboo fibers increased,and their microstructure changed from dense and flat to wrinkled and porous simultaneously.The adsorption experiments showed that the modified bamboo fibers achieved significantly higher adsorption rates of cadmium(Cd)and lead(Pb)than natural bamboo fibers(up to 47.37%and 44.57%,respectively),and could also be applied to a wider pH value range.The adsorption of Cd and Pb by modified and unmodified bamboo fibers conformed to both Langmuir and Freundlich thermodynamic models.Besides,after modification the maximum adsorption capacity(Q_(m))of the bamboo fibers for Cd and Pb increased from 8.9687mg/g and 11.5075mg/g to 26.1780mg/g and 32.3625mg/g respectively,indicating that the modification process of succinic acid increased the adsorption sites of the bamboo fibers,and thus improved their adsorption capacity of Cd/Pb,which can provide a new idea for the modification and upgrading of biosorbent materials.

关 键 词：琥珀酸 竹纤维 酯化改性 镉 铅 

分 类 号：X703.5[环境科学与工程—环境工程]