Novel magnetic chitosan/poly(vinyl alcohol) hydrogel beads: preparation, characterization and application for adsorption of dye from aqueous solution.
Novel magnetic chitosan/poly(vinyl alcohol) hydrogel beads: preparation, characterization and application for adsorption of dye from aqueous solution.
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DOI：
10.1016/j.biortech.2011.11.057
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发表时间：
2012-02
影响因子：
11.4
通讯作者：
Hua-yue Zhu;Yong-Qian Fu;R. Jiang;Jun Yao;Ling Xiao;G. Zeng
中科院分区：
文献类型：
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作者：
Hua-yue Zhu;Yong-Qian Fu;R. Jiang;Jun Yao;Ling Xiao;G. Zeng
采用瞬时凝胶法制备了新型壳聚糖/聚乙烯醇磁性水凝胶珠（m-CS/PVA HBs），并用x射线衍射（XRD）、振动样品磁强计（VSM）和热重分析（TGA）对其进行了表征。表征结果表明，在不破坏fe3o4晶体结构的情况下成功制备了m-CS/PVA HBs，其饱和磁化强度约为21.96emug−1。刚果红在m-CS/PVA HBs上的吸附量为470.1mg−1。拟二级动力学和Langmuir方程很好地描述了吸附过程。焓变的正值（ΔH°）（13.32kJmol−1）表明吸附是吸热和物理性质的。在298K时，m-CS/PVA HBs的吉布斯自由能变化（ΔG°）为−3.321kJmol−1k，表明刚果红吸附的自发性。因此，m-CS/PVA HBs可以作为其他吸附剂的低成本替代品，用于去除水溶液中的染料。
Novel magnetic chitosan/poly(vinyl alcohol) hydrogel beads (m-CS/PVA HBs) were prepared by an instantaneous gelation method and characterized by X-ray diffraction (XRD), vibrating sample magnetometry (VSM) and thermogravimetric analysis (TGA). Results of characterization indicated that m-CS/PVA HBs have been prepared successfully without damaging the crystal structure of Fe3O4and their saturation magnetization were about 21.96emug−1. The adsorption capacity of Congo Red on the m-CS/PVA HBs was 470.1mgg−1. The adsorption was well described by pseudo-second-order kinetics and Langmuir equation. Positive value of enthalpy change (ΔH∘) (13.32kJmol−1) showed that the adsorption was endothermic and physical in nature. The values of Gibbs free energy change (ΔG∘) were found to be −3.321kJmol−1at 298K for m-CS/PVA HBs, indicating the spontaneity of Congo Red adsorption. Therefore, the m-CS/PVA HBs could be employed as a low-cost alternative to other adsorbents in the removal of dyes from aqueous solution.