羧甲基纤维素钠/己二酸二酰肼水凝胶的制备及其重金属离子吸附性能研究

Study on Preparation of Sodium Carboxymethyl Cellulose/Adipic Dihydrazide Hydrogel and Its Adsorption Performance for Heavy Metal Ions

中文关键词:  羧甲基纤维素钠（CMC）  己二酸二酰肼（ADH）  水凝胶  重金属离子  废水

Key Words:sodium carboxymethyl cellulose （CMC）  adipic dihydrazide （ADH）  hydrogel  heavy metal ions  wastewater

中文摘要:

      以羧甲基纤维素钠（CMC）为基材、己二酸二酰肼（ADH）为交联剂，成功制备了具有三维网络结构的CMC/ADH水凝胶，研究了CMC/ADH水凝胶对废水中重金属离子（Cr⁶⁺、Cu²⁺、Pb²⁺）的吸附性能。采用傅里叶变换红外光谱（FT-IR）、扫描电子显微镜（SEM）、X射线能谱分析（EDS）和溶胀性能分析等方法对CMC/ADH水凝胶进行表征；研究了吸附时间、pH值及重金属离子初始浓度对CMC/ADH水凝胶在模拟废水中吸附行为的影响；并对CMC/ADH水凝胶的吸附机理进行分析研究。结果表明，在室温（25℃）、pH值=3、重金属离子初始浓度50 mg/L、吸附时间300 min的条件下，CMC/ADH水凝胶对废水中Cr⁶⁺、Cu²⁺和Pb²⁺的吸附量分别为31.5、75.9和72.0 mg/g；其吸附过程的动力学模型和等温模型的拟合结果表明，CMC/ADH水凝胶吸附重金属离子的过程是单层化学吸附过程。

Abstract:

      The sodium carboxymethyl cellulose/adipic dihydrazide （CMC/ADH） hydrogel with three-dimensional network structure was successfully prepared by using CMC as the substrate and ADH as the cross-linking agent. The adsorption performance of the CMC/ADH hydrogel on heavy metal ions （Cr⁶⁺， Cu²⁺， and Pb²⁺） in wastewater was studied. The as-prepared hydrogel was characterized through Fourier transform infrared spectroscopy （FT-IR）， scanning electron microscope （SEM）， X-ray energy spectrum analysis （EDS）， and swelling performance analysis. The effects of adsorption time， pH value， and initial concentration of heavy metal ion on the adsorption process of CMC/ADH hydrogel in simulated wastewater， and the mechanism of which were studied. The results showed that the adsorption capacities of CMC/ADH hydrogel for Cr⁶⁺， Cu²⁺， and Pb²⁺ were 31.5， 75.9， and 72.0 mg/g， respectively， at room temperature （25℃）， pH value of 3， initial concentration of heavy metal ion of 50 mg/L， and adsorption time of 300 min. The kinetic model and isothermal model fitting results of the adsorption process showed that adsorption of CMC/ADH hydrogel on heavy metal ions was a monolayer chemical process.