Abstract:

Zn²⁺ was used as template with paraffin as dispersant agent，formaldehyde as pre-crosslinking agent，and epichlorohydrin as crosslinking agent to prepare a imprinted chitosan polymer. The structure of the polymer was characterized by X ray diffractometer （XRD）.. The dosage of the polymer and the influence of temperature on the adsorption of Zn²⁺ were studied. Studies on the kinetics of the adsorption of Zn²⁺ by the imprinted polymer and the isothermal adsorption properties were also performed. The result showed that the regularity of the chitosan crystals was broken in the preparation of the imprinted polymer，adding a large amount of coordination group which enlarged adsorption capacity. Meanwhile the polymer acquired a highly selective adsorption capacity to Zn²⁺，and the separation factor of Zn²⁺，Cd²⁺，Mg²⁺，Mn²⁺ were all greater than 1.5. The imprinted polymer adsorbed the Zn²⁺ rapidly，and the whole adsorption process fitted the pseudo-second-order kinetic model well，t/Q_t=8.1744+2.0186t and the correlation coefficient was 0.998. The calculated equilibrium adsorption capacity was satisfactory compared with the experiment data. The adsorption process at a constant temperature fitted the Langmuir equation of isothermal adsorption：C_e/Q_e=1.3297+0.02701C_e and the maximum adsorption capacity was 37.023 mmol/g. The adsorption mainly proceeded in the form of monolayer.

摘要：

以Zn²⁺作为模板，加入分散剂石蜡、预交联剂甲醛、交联剂环氧氯丙烷，制得特性壳聚糖印迹聚合物，用X射线衍射仪表征了聚合物的结构，考察了聚合物用量、温度等对吸附Zn²⁺的影响，研究了印迹聚合物对Zn²⁺的吸附动力学、等温吸附特性。结果表明，印迹聚合物合成过程中打破了壳聚糖原有晶体的规整性，增加了大量的配位基团，使聚合物的吸附容量大大增加，同时聚合物对Zn²⁺有很好的选择吸附性，对Zn²⁺、Cd²⁺、Mg²⁺、Mn²⁺溶液的分离因子均大于1.5；印迹聚合物能快速吸附溶液中Zn²⁺，整个吸附过程符合拟二级动力学模型：t/Q_t=8.1744+2.0186t，相关系数为0.998，吸附平衡容量模型计算值与实验值较为吻合；印迹聚合物对Zn²⁺的等温吸附过程符合Langmuir吸附等温吸附模型：C_e/Q_e=1.3297+0.02701C_e，最大吸附容量为37.023 mmol/g，吸附过程主要以单分子层的吸附形式进行。