羧基化磁性Fe_(3)O_(4)复合材料的制备及其对水体中Pb^(2+)的吸附研究  

Synthesis of Carboxylated Magnetic Fe_(3)O_(4) Composites and Their Adsorption Behavior to Pb^(2+)

作　　者：李美兰 豆小喻[1] 何娇 龚伟 解程程 刘白玲[2] LI Meilan;DOU Xiaoyu;HE Jiao;GONG Wei;XIE Chengcheng;LIU Bailing(Key Laboratory of Comprehensive Utilization of Tailings Resources in Shanxi Province,Shangluo University,Shangluo 726000,China;Chengdu Institute of Organic Chemistry,Chinese Academy of Sciences,Chengdu 610041,China)

机构地区：[1]商洛学院陕西省尾矿资源综合利用重点实验室,陕西商洛726000 [2]中国科学院成都有机化学研究所,成都610041

出　　处：《中国塑料》2021年第10期37-44,共8页China Plastics

基　　金：陕西省科技厅项目(2019JQ-907);陕西省科技厅项目(2019JQ-908);国家级大学生创新创业训练计划项目(201911396025);商洛学院自然科学基金项目(16SKY026)。

摘　　要：以采用共沉淀法制备的磁性Fe_(3)O_(4)为核,通过硅烷化及酰胺化反应,制备了羧基化磁性Fe_(3)O_(4)复合材料(Fe_(3)O_(4)-Si O_(2)-NH-COOH),通过红外光谱仪(FTIR)、扫描电子显微镜(SEM)、透射电子显微镜(TEM)、磁强度计(VSM)和X射线衍射仪(XRD)等对复合材料的结构进行了表征,并对不同作用条件下Fe_(3)O_(4)-Si O_(2)-NH-COOH吸附Pb^(2+)的效果及Fe_(3)O_(4)-Si O_(2)-NH-COOH的重复使用效能进行了研究。结果表明,具有Fe_(3)O_(4)-Si O_(2)-NH-COOH结构的复合材料已被成功被制备,且该材料仍然能够实现快速磁性分离;Fe_(3)O_(4)-Si O_(2)-NH-COOH对Pb^(2+)的静态吸附动力学数据更符合准二阶动力学,吸附时间为100 min、p H=4.5、Fe_(3)O_(4)-Si O_(2)-NH-COOH用量为1.0 g/L时,Fe_(3)O_(4)-Si O_(2)-NH-COOH对Pb^(2+)的最大吸附容量为208.7 mg/g,且Langmuir方程更能描述该吸附等温过程;Fe_(3)O_(4)-Si O_(2)-NH-COOH对Pb^(2+)的吸附是吸热过程;Fe_(3)O_(4)-Si O_(2)-NH-COOH对Pb^(2+)的吸附量随时间延长先增加后趋于稳定,随p H值的增加先增加后减小;相比于一价阳离子,溶液中二价Ca^(2+)、Mg^(2+)的存在对吸附反应具有一定抑制作用;Fe_(3)O_(4)-Si O_(2)-NH-COOH吸附Pb^(2+)后可洗脱再生,连续重复使用6次后对Pb^(2+)的去除率仍大于50%。Fe_(3)O_(4) magnetic particles were prepared by co-precipitation and then surface-treated through silanization and amidation reactions to obtain a carboxylated composite(Fe_(3)O_(4)-Si O_(2)-NH-COOH).The structure of Fe_(3)O_(4)-SiO_(2)-NH-COOH,the effect of reaction condition on the Pb^(2+)adsorption of the Fe_(3)O_(4)-Si O_(2)-NH-COOH and its repetitive utilization efficiency was analyzed by FTIR,SEM,TEM,VSM and XRD.The results indicated that the Fe_(3)O_(4)-Si O_(2)-NH-COOH were successfully prepared with a desired structure and could be obtained through a rapid magnetic separation.Meanwhile,the static adsorption experiment showed that the adsorption kinetics belonged to the second order.The adsorption system reached an equilibrium with a maximum adsorbent capacity of 207.8 mg/g with a p H 4.5,a temperature of55℃,a contact time of 100 min,and an Fe_(3)O_(4)-Si O_(2)-NH-COOH concentration of 1.0 g/L.The Langmuir equation is able to better describe the adsorption isotherm,indicating an endothermic process for the adsorption of Pb^(2+).The adsorption capacity of Fe_(3)O_(4)-Si O_(2)-NH-COOH toward Pb^(2+)showed an increase at first and then tended to stabilize with an increase in time.However,it increased at first and then decreased with an increase in p H.Compared to monovalent cations,the presence of divalent Ca^(2+)and Mg^(2+)in the solution could generate a certain inhibitory effect on the adsorption reaction.The Pb^(2+)removal rate was still above 50%after regeneration of Fe_(3)O_(4)-Si O_(2)-NH-COOH for six times.

关 键 词：羧基化 吸附 铅离子 结构 磁性 复合材料 

分 类 号：TQ317[化学工程—高聚物工业]