核化学与放射化学Issue(z1)：13-20,8.DOI:10.7538/hhx.2014.36.S0.0013
粉煤灰衍生介孔硅钙材料吸附去除Co(Ⅱ)及放射性过渡金属离子性能研究
Removal of Co (Ⅱ)and Radioactive Transition Metal Ions by Adsorption on Fly Ash-Derived Mesoporous Calcium-Silicate Material
摘要
Abstract
To meet the needs of treatment of waste water containing low-level radioactive transition metal ions,using Co (Ⅱ)as a representative,the sorption ability of Co (Ⅱ)on calcium-silicate material,which is produced at the pre-desilication stage during the alumina extraction from the high-alumina fly ash by pre-desilication-soda-lime sintering technique,was studied.The results indicate that the calcium-silicate material,with hydration calcium silicate (C—S—H(Ⅰ))as the main mineral,is one of those mesoporous materials with high specific surface area(733 m2/g)and developed void space structure.The material also has good acid and alkali buffer performance(pH=2-10)and cation exchange capacity(Ca2+/H+).The adsorption capacity can reach 209-296 mg/g in the temperature range of 35-60 ℃for Co(Ⅱ).The adsorption process is endothermic and consistent with Langmuir monolayer chemical adsorption.The adsorption equilibrium can be reached quickly within 3 h.Our results show that the main adsorption mechanism is most ion exchange(84.5%).Moreover, the adsorption results for nuclear power plant overhaul wastewater show that more than 98.6% of the radioactive cobalt as well as other radioactive transition metal ions are removed.Speaking from the perspective of practical application,the mesoporous calcium-silicate material not only has high compatibility with cement which is good to the radionu-clide stabilization,but also can replace part of cement to achieve the reduction of the radioac-tive solidification blocks.Because of the above mentioned environmental and economic bene-fits,the mesoporous calcium-silicate material evidently has potential application in radioac-tive transition nuclide removal of wastewater.关键词
Co(Ⅱ)/介孔硅钙材料/吸附/离子交换Key words
Co(Ⅱ)/mesoporous calcium-silicate material/adsorption/ion exchange分类
资源环境引用本文复制引用
雷雪飞,祁光霞,孙应龙,李磊,袁超,王毅,孙俊民..粉煤灰衍生介孔硅钙材料吸附去除Co(Ⅱ)及放射性过渡金属离子性能研究[J].核化学与放射化学,2014,(z1):13-20,8.基金项目
清华大学人才支持基金项目 （）
