功能化石墨烯吸附模拟反应堆冷却剂中银的研究

Adsorption Behavior of Silver on Functional Graphene in Simulated Reactor Coolant

设计合成了四氧化三铁/石墨烯/聚乙烯亚胺复合材料(PMRGO),通过红外光谱、透射电镜、拉曼光谱和XPS等手段表征了PMRGO的化学组成和结构,并研究了该材料在模拟压水堆冷却剂环境下对银离子和银胶体的吸附性能。结果表明,PMRGO在模拟冷却剂条件下对银有良好的吸附性能,对银的吸附在pH=3~8范围内随pH值的升高而增大。随着银初始浓度的增大,PMRGO对银的吸附率逐渐升高。当银初始浓度为5 mg/L时,PMRGO对银离子吸附24 h后基本达到平衡,吸附量可达136 mg/g;对银胶体吸附30 min后基本达到平衡,吸附量可达169 mg/g。吸附等温线符合Langmuir方程,吸附动力学可用准二级动力学方程来描述。

A composite of polyethyleneimine/magnetite/reduced grapheme oxide(PMRGO)was designed and synthesized,and its structure and chemical composition were characterized by Fourier-transformed infrared spectroscopy(FTIR),transmission electron microscope(TEM),Raman spectroscopy and X-ray photoelectron spectroscopy(XPS).The adsorption performance of Ag ions and colloid on PMRGO were studied in simulated pressurized water reactor coolant.The results show that PMRGO exhibits excellent adsorption performance on silver except boron and lithium ions in the simulated coolant,and the adsorption capacity increases with pH value from 3 to 8.With the increase of initial concentration of Ag,the adsorption rate of Ag on the PMRGO gradually increases.When the initial concentration of Ag is 5 mg/L,the adsorption capacity can reach 136 mg/g for Ag ions after oscillating 24 h,while for Ag colloid tends to be stable after 30 min,and the adsorption capacity is 169 mg/g.The adsorption isotherm is consistent with the Langmuir equation,and the adsorption kinetics can be described by the quasi-secondary kinetic equation.