聚乙烯亚胺改性蔗渣纤维素/蒙脱土复合球的制备及对Cd(Ⅱ)的吸附  

Preparation of polyethyleneimine modified bagasse cellulose/montmorillonite composite spheres and their performance on adsorption of Cd(Ⅱ)

作　　者：付欣 蔡平雄 潘远凤[1] FU Xin;CAI Pingxiong;PAN Yuanfeng(Guangxi Colleges and Universities Key Laboratory of New Chemical Application Technology in Resource,School of Chemistry and Chemical Engineering,Guangxi University,Nanning 530004,Guangxi,China;College of Petroleum and Chemical Engineering,Beibu Gulf University,Qinzhou 535011,Guangxi,China)

机构地区：[1]广西大学化学化工学院,广西资源化工应用新技术高校重点实验室,广西南宁530004 [2]北部湾大学石油与化工学院,广西钦州535011

出　　处：《精细化工》2023年第11期2535-2543,共9页Fine Chemicals

基　　金：国家自然科学基金项目(22068006)。

摘　　要：以聚乙烯亚胺(PEI)改性甘蔗渣纤维素(SBC)(记为PEI-SBC)和改性蒙脱土(SMt)为原料,CaCO_(3)为致孔剂,通过简单凝固浴法制备了PEI-SBC/Mt复合球。采用FTIR、SEM、XRD、TGA、N_(2)吸附对其进行了表征,考察了溶液初始pH、Cd(Ⅱ)初始质量浓度、吸附温度、吸附时间对PEI-SBC/Mt吸附Cd(Ⅱ)的影响,并分析了该吸附剂对Cd(Ⅱ)的吸附机理。结果表明,在25℃、溶液初始pH=6、Cd(Ⅱ)初始质量浓度为450 mg/L、吸附时间120min时,PEI-SBC/Mt对Cd(Ⅱ)的最大平衡吸附量为235mg/g。准二级动力学模型和Langmuir模型能够准确描述吸附过程,PEI的加入为吸附剂吸附Cd(Ⅱ)提供了更多的活性位点。此外,吸附剂具有可重复使用性,经过5次循环吸脱附后,其吸附率只由起始的94.0%降至79.8%。PEI-SBC/Mt composite spheres were synthesized from polyethyleneimine(PEI)modified bagasse cellulose(SBC)(PEI-SBC)and modified montmorillonite(SMt)using calcium carbonate as pore-forming agent via simple coagulation bath method,and characterized by FTIR,SEM,XRD,TGA,N_(2) adsorption.The effects of initial solution pH,initial Cd(Ⅱ)mass concentration,adsorption temperature and adsorption time on the performance of PEI-SBC/Mt on adsorption of Cd(Ⅱ)were then investigated,followed by analysis on the adsorption mechanism.The results showed that the maximum equilibrium capacity of PEI-SBC/Mt for adsorption of Cd(Ⅱ)reached 235 mg/g under the conditions of 25℃,pH=6 and initial Cd(Ⅱ)mass concentration of 450 mg/L.The adsorption process,which was single-molecule chemisorption with PEI providing more active sites,could be accurately described by the quasi-second-order kinetic model and Langmuir model.Moreover,the adsorbent was reusable and its adsorption capacity only decreased from the original 94.0%to 79.8%after five cycles of adsorption and desorption.

关 键 词：甘蔗渣纤维素 复合球 吸附 Cd(Ⅱ) 吸附机理 水处理技术 

分 类 号：X703[环境科学与工程—环境工程] TQ424[化学工程]