β-环糊精/氧化石墨烯制备及对Co^(2+)吸附性能

Preparation ofβ-Cyclodextrin/Graphene oxide and its adsorption property for Co^(2+)

为有效去除放射性废水中的Co^(2+),采用Hummer法制备氧化石墨烯(GO),并进一步合成了β-环糊精/氧化石墨烯复合材料(β-CD/GO)。利用扫描电镜、红外光谱、X射线衍射等仪器对材料进行了表征,并通过静态吸附实验对其吸附水中Co^(2+)的影响因素进行了研究。研究结果表明:在pH值为6,温度为30℃时,经3 h,β-CD/GO对Co^(2+)的吸附达到平衡;在初始质量-体积浓度小于30 mg/L时,材料对Co^(2+)的去除率达到100%;当初始质量-体积浓度为100 mg/L,静态吸附容量可达到150.3 mg/g,对Co^(2+)的去除率达到60%。β-CD/GO对Co^(2+)的吸附过程可用Langmuir等温吸附模型和准二级动力学方程进行描述,吸附过程属于单分子层的化学吸附。Boyd模型与Werber-Morris模型的拟合结果表明:吸附过程主要为颗粒内扩散。

To remove Co^(2+)in radioactive waste water,grapheme oxide(GO)was prepared by using Hummer method,andβ-cyclodextrin/GO was further synthesized.The materials were characterized by scanning electron microscopy,infrared spectroscopy,X-ray diffraction and other instruments,and the influencing factors of Co^(2+)adsorption in water were studied by static adsorption experiment.The results show that at pH=6 and when the temperature is 30℃,the adsorption is up to equilibrium after 3 h.When the initial mass volume concentration is less than 30 mg/L,the Co^(2+)removal rate by the material reaches 100%.When the initial mass volume concentration is 100 mg/L,the static adsorption capacity can reach 150.3 mg/g,and the Co^(2+)removal rate by the material reaches 60%.The adsorption process ofβ-CD/GO for Co^(2+)can be described by Langmuir isothermal adsorption model and quasi-second-order kinetic equation,and the adsorption process belongs in monomolecular chemisorptions.The fitting results of Boyd model and Werber-Morris model show that the adsorption process is mainly diffusion within particles.