王迎亚¹,施华珍¹,张寒冰^1,2,于姝敏²,陈宁华²,童张法^1,3

• 1:广西大学 化学化工学院，广西石化资源加工及工程强化技术重点实验室，广西 南宁 530004
• 2:广西大学 环境学院，广西 南宁 530004
• 3:广西碳酸钙产业化工程院，广西 南宁 530004

摘要(Abstract)：

为改善膨润土对Cr（VI）的吸附性能，并提高其固液分离回收能力，研究构筑了一种壳聚糖修饰的复合磁性吸附材料——磁性柠檬酸膨润土（Magnetic Citric Acid Bentonite，MCAB），并利用SEM、XRD、VSM、FT-IR对改性前后的材料进行表征对比，结果表明壳聚糖中的-NH₂、-OH等功能基团及磁性Fe₃O₄微粒均负载到柠檬酸膨润土（Citric Acid Bentonite，CAB）上。MCAB对Cr（VI）的吸附性能研究结果显示：相对于CAB，复合后的MCAB吸附性能明显提高，并具有良好的磁分离能力；pH值对Cr（VI）的吸附影响较大，最佳pH值在2.0~3.0；当吸附剂投加量为1.6 g·L^-1、pH值为3.0、Cr（VI）的初始浓度为10 mg·L^-1时，MCAB对Cr（VI）的去除率高达99%；吸附等温方程和动力学方程的拟合结果分别符合Langmuir吸附等温模型和准二级动力学模型。由于MCAB上修饰的-NH₂在酸性条件下易质子化，会增强对Cr（VI）的静电吸引作用，因此MCAB对Cr（VI）的吸附去除率得到了明显提高；同时，加磁赋予了CAB快速的固液分离能力。研究表明MCAB对模拟废水中的Cr（VI）去除效果良好，有望应用于实际废水中Cr（VI）的去除。

关键词(KeyWords)： 柠檬酸膨润土;Fe₃O₄;壳聚糖;Cr（VI）;吸附

Abstract:

Keywords:

基金项目(Foundation): 国家自然科学基金（21576055）；广西碳酸钙产业化工程院开放课题（TSG201501）；广西教育厅科研资助项目（LX2014005）。

作者(Author): 王迎亚¹,施华珍¹,张寒冰^1,2,于姝敏²,陈宁华²,童张法^1,3

DOI: 10.3969/j.issn.1003-9015.2017.03.030

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