聚天冬氨酸/木质纤维素水凝胶对Pb(Ⅱ)的吸附及脱附性能  

Performance of Adsorption and Desorption of Pb(Ⅱ) by Polyaspartic Acid/Lignocellulose Hydrogels

作　　者：叶满辉 王丽[1] 杜慧琴[1] 

机构地区：[1]内蒙古农业大学材料科学与艺术设计学院,内蒙古呼和浩特010018

出　　处：《高分子材料科学与工程》2016年第11期63-69,共7页Polymer Materials Science & Engineering

基　　金：内蒙古农业大学优秀青年科学基金项目(2014XYQ-12);内蒙古自然科学基金资助项目(2016MS0210)

摘　　要：以聚天冬氨酸(PASP)与木质纤维素(LNC)水溶液聚合法制备出的聚天冬氨酸/木质纤维素水凝胶(PASP/LNC)为吸附剂,对Pb(Ⅱ)进行吸附及脱附实验,研究溶液的初始离子浓度、pH值、吸附时间和吸附温度对溶液中Pb(Ⅱ)吸附量的影响。结果表明,溶液中Pb(Ⅱ)初始离子浓度为0.04 mol/L,溶液pH值为5.5,吸附时间为120 min,吸附温度为30℃时,PASP/LNC水凝胶对Pb(Ⅱ)的吸附量达到最大为972.35 mg/g。吸附过程符合准二级动力学模型,吸附等温线符合Langmuir模型。采用X射线衍射分析、比表面积和平均孔径分析、扫描电镜、傅里叶变换红外光谱分析PASP/LNC水凝胶的结构和吸附机理。使用HNO_3对PASP/LNC进行脱附实验。结果表明,HNO_3浓度为0.04 mol/L,脱附温度为30℃,脱附时间达到60 min时,最大脱附量为928.36 mg/g。吸附/脱附循环实验表明,PASP/LNC水凝胶重复使用4次后吸附量仍较高,是一种可重复使用的高效吸附材料。The polyaspartic acid/Lignocellulose （PASP-LNC） hydrogels prepared were taken as adsorbent to research the adsorption and desorption properties of Ph （ Ⅱ ）, which were synthesized by polymerization in static solution of PASP and LNC. The effecting parameters on the Pb （ Ⅱ ） adsorption capacity by changing initial concentration of Pb（Ⅱ）, solution pH value, adsorption time and adsorption temperature were studied in detail. The result show that the best adsorption capacity of PASP/LNC hydrogels for Pb（Ⅱ ） could be 978.35 mg/g under the condition, the initial concentration of Pb（Ⅱ ） is 0.04 mol/L, the solution pH value is 5.5, the adsorption time is 120 min and the adsorption temperature is 30℃. The pseudo-second-order kinetic model could well describe the whole adsorption process, and the isotherm adsorption equilibrium is conformed to the Langmuir model. The structure and adsorption mechanism of PASP/LNC were researched in combination with results of XRD, BET specific surface area and average pore, SEM and FT-IR. HNCh was used to perform desorption of PASP/LNC. The results show that with the HNCO3 concentration of 0.04 mol/L, desorption temperature of 30 ＂C and desorption time of 60 rain, the satisfactory effect of desorption capability is 928.36 mg/g. The adsorption/desorption cycle experiment indicates that the adsorption capability of PASP/LNC is ideal for four cycles, so PASP/LNC is confired as a high efficient adsorbent for recycling.

关 键 词：聚天冬氨酸 木质纤维素 水凝胶 Pb(Ⅱ) 吸附 脱附 

分 类 号：O636.11[理学—高分子化学]