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研究了甲醛、环氧氯丙烷交联壳聚糖树脂(AECTS)对Ni(II)的吸附行为和吸附Ni(II)对树脂结构及性能的影响.用FTIR,WAXD,TGA和DSC对吸附产物进行了结构表征,并深入分析了AECTS与Ni(II)之间的作用机理.结果表明:AECTS主要以配位形式吸附Ni(II);AECTS吸附Ni(II)后,结晶度下降、总体上热稳定性变差;Ni(II)对AECTS的主链分解具有明显的催化功能,而空气气氛中对AECTS在500℃附近的分解表现出火焰缓蚀作用.AECTS对Ni(II)的吸附行为符合Langmuir模型,属于单分子层吸附,所有吸附位对Ni(II)的作用近似相同;与壳聚糖(CTS)比较,造成AECTS对Ni(II)吸附量增大的主要原因是AECTS结晶度下降和孔隙率增加,二者导致在交联处理前Ni(II)难于接近的吸附位点“活性”相对增大,使其更容易与Ni(II)相结合;不同介质对AECTS吸附Ni(II)的影响大小顺序为HCl>CdCl2>MgCl2>NaCl,前两者使吸附量减小,MgCl2使吸附量稍有增加,NaCl对吸附量基本没有影响.
The adsorption behavior of Ni (II) and the adsorption of Ni (II) on the structure and properties of the resin were studied by using formaldehyde and epichlorohydrin cross-linked chitosan resin (AECTS) (II). The results showed that AECTS mainly adsorbed Ni (II) on the coordination sites and the crystallinity decreased after AECTS adsorbed Ni (II). On the whole, Ni (II) has a significant catalytic function for the main chain decomposition of AECTS, while flame retardation of AECTS decomposes in the vicinity of 500 ℃ in air atmosphere.The adsorption behavior of AECTS on Ni (II) Which is consistent with the Langmuir model and belongs to the monolayer adsorption. All the adsorption sites have the same effect on Ni (II). Compared with the CTS, the main reason for the increase of AECTS on Ni (II) adsorption is AECTS crystallinity (P <0.01), and the porosity increased. Both of them lead to a relatively increase of “activity” of Ni (II) adsorption site which is difficult to access before crosslinking treatment, making it easier to combine with Ni II) in the order of HCl> CdCl2> MgCl2> NaCl, the former two decreased the adsorption capacity, while MgCl2 slightly increased the adsorption capacity. NaCl Adsorption of no effect.