中国塑料 ›› 2021, Vol. 35 ›› Issue (10): 37-44.DOI: 10.19491/j.issn.1001-9278.2021.10.007

• 材料与性能 • 上一篇    下一篇

羧基化磁性Fe3O4复合材料的制备及其对水体中Pb2+的吸附研究

李美兰1,2(), 豆小喻1, 何娇1, 龚伟1,2(), 解程程1, 刘白玲2   

  1. 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
  • 收稿日期:2021-04-07 出版日期:2021-10-26 发布日期:2021-10-27
  • 作者简介:李美兰(1988—),女,讲师,从事生态高分子材料研究,liecho2009@163.com
  • 基金资助:
    陕西省科技厅项目(2019JQ-907);国家级大学生创新创业训练计划项目(201911396025);陕西省科技厅项目(2019JQ-908);商洛学院自然科学基金项目(16SKY026)

Synthesis of Carboxylated Magnetic Fe3O4 Composites and Their Adsorption Behavior to Pb2+

LI Meilan1,2(), DOU Xiaoyu1, HE Jiao1, GONG Wei1,2(), XIE Chengcheng1, LIU Bailing2   

  1. 1.Key Laboratory of Comprehensive Utilization of Tailings Resources in Shanxi Province,Shangluo University,Shangluo 726000,China
    2.Chengdu Institute of Organic Chemistry,Chinese Academy of Sciences,Chengdu 610041,China
  • Received:2021-04-07 Online:2021-10-26 Published:2021-10-27
  • Contact: GONG Wei E-mail:liecho2009@163.com;com@163.com

摘要:

以采用共沉淀法制备的磁性Fe3O4为核,通过硅烷化及酰胺化反应,制备了羧基化磁性Fe3O4复合材料(Fe3O4?SiO2?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Fe3O4?SiO2?NH?COOH吸附Pb2+的效果及Fe3O4?SiO2?NH?COOH的重复使用效能进行了研究。结果表明,具有Fe3O4?SiO2?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;Fe3O4?SiO2?NH?COOH对Pb2+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、pH=4.5、Fe3O4?SiO2?NH?COOH用量为1.0 g/L时,Fe3O4?SiO2?NH?COOH对Pb2+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;Fe3O4?SiO2?NH?COOH对Pb2+的吸附是吸热过程;Fe3O4?SiO2?NH?COOH对Pb2+的吸附量随时间延长先增加后趋于稳定,随pH值的增加先增加后减小;相比于一价阳离子,溶液中二价Ca2+、Mg2+的存在对吸附反应具有一定抑制作用;Fe3O4?SiO2?NH?COOH吸附Pb2+后可洗脱再生,连续重复使用6次后对Pb2+的去除率仍大于50 %。

关键词: 羧基化, 吸附, 铅离子, 结构, 磁性, 复合材料

Abstract:

Fe3O4 magnetic particles were prepared by co?precipitation and then surface?treated through silanization and amidation reactions to obtain a carboxylated composite (Fe3O4?SiO2?NH?COOH). The structure of Fe3O4?SiO2?NH?COOH, the effect of reaction condition on the Pb2+ adsorption of the Fe3O4?SiO2?NH?COOH and its repetitive utilization efficiency was analyzed by FTIR, SEM, TEM, VSM and XRD. The results indicated that the Fe3O4?SiO2?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 pH 4.5, a temperature of 55 ℃, a contact time of 100 min, and an Fe3O4?SiO2?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 Pb2+. The adsorption capacity of Fe3O4?SiO2?NH?COOH toward Pb2+ 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 pH. Compared to monovalent cations, the presence of divalent Ca2+ and Mg2+ in the solution could generate a certain inhibitory effect on the adsorption reaction. The Pb2+ removal rate was still above 50 % after regeneration of Fe3O4?SiO2?NH?COOH for six times.

Key words: carboxylation, adsorption, lead ion, structure, magnetism, composite

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