淀粉/高岭土-g-(AA-AM-AMPS)高吸水性聚合物对Cu^(2+)、Fe^(3+)的吸附特性

Adsorption property of starch/kaolin-g-(AA-AM-AMPS)superabsorbent polymer for Cu^(2+) and Fe^(3+)

以玉米淀粉/高岭土为基体,采用超声波辅助二次聚合法制备了淀粉/高岭土-g-(AA-AM-AMPS)高吸水性聚合物。利用扫描电镜(SEM)、红外光谱(FT-IR)、X射线衍射(XRD)和热重分析(TG)对聚合物进行表征分析。考察了淀粉与高岭土质量比对聚合物吸水性能的影响,聚合物在不同浓度的硫酸铜溶液和硫酸铁溶液中的吸附特性,并采用准一级动力学模型、准二级动力学模型研究了聚合物对Cu^(2+)、Fe^(3+)的吸附行为。结果表明,当m_((淀粉))∶m_((高岭土))=4∶1时,制得的聚合物吸水倍率最高;在CuSO_(4)初始浓度为0.005~0.05mol/L的范围内,聚合物对Cu^(2+)的最大吸附量为217.27mg/g,Cu^(2+)最佳去除率为64.17%;在Fe_(2)(SO_(4))_(3)初始浓度为0.005~0.05mol/L的范围内,聚合物对Fe^(3+)的最大吸附量为325.93mg/g,对Fe^(3+)的最佳去除率为64.30%;准二级动力学模型能更好地描述淀粉/高岭土-g-(AA-AM-AMPS)对Cu^(2+)、Fe^(3+)的吸附行为。此研究可为淀粉/高岭土复合基高吸水性聚合物在废水处理领域的开发应用提供参考。

Using corn starch and kaolin as composite matrix,the starch/kaolin-g-(AA-AM-AMPS)superabsorbent polymer was prepared by ultrasonic-assisted secondary polymerization.The polymer was characterized by scanning electron microscopy(SEM),infrared spectroscopy(FT-IR),X-ray diffraction(XRD)and thermogravimetric analysis(TG).The effect of the mass ratio of starch to kaolin on the water absorption of polymer was studied.The adsorption characteristics of the polymer in different concentrations of copper sulfate solution and ferric sulfate solution were studied.The adsorption behavior of the polymer on Cu^(2+) and Fe^(3+) was studied by using quasi-first order kinetic model and quasi-second order kinetic model.The results showed that when m_((starch))∶m_((kaolin))=4∶1,the polymer had the highest water absorption rate.When the initial concentration of CuSO_(4) was 0.005~0.05mol·L^(-1),the maximum adsorption capacity of Cu^(2+) was 217.27mg·g^(-1),and the optimal Cu^(2+) removal rate was 64.17%.In the range of initial concentration of Fe_(2)(SO_(4))_(3) from 0.005 to 0.05mol·L^(-1),the maximum adsorption capacity of Fe^(3+) was 325.93mg·g^(-1),and the optimal Fe^(3+) removal rate was 64.30%.The quasi-second-order kinetic model can better describe the adsorption behavior of starch/kaolin-g-(AA-AM-AMPS)for Cu^(2+) and Fe^(3+).The results can provide reference for the development and application of starch/kaolin composite based superabsorbent polymer in wastewater treatment field.