硅球/亚铁氰化铜钾复合物固定床选择性去除污染水体中的Cs^(+)及其影响因素

Selective Removal of Cs^(+)From Contaminated Water Using Silicon Bead/Potassium Copper Ferrocyanide Composites in Fixed-Bed

采用柱上淋洗方式,在硅球(SiO_(2))填料上原位负载亚铁氰化铜钾(Cu-PBA),制得SiO_(2)/Cu-PBA复合材料固定床吸附柱。采用扫描电镜-能谱(SEM-EDS)、红外光谱(FTIR)、粉末X射线衍射(XRD)和N_(2)吸附等温测试等手段对材料进行表征,证实了Cu-PBA的成功负载。通过批式法吸附实验,明确了SiO_(2)/Cu-PBA在模拟地下水中对Cs^(+)的最大吸附容量约为4.0 mg/g,30 min内达吸附平衡。进而系统研究了该材料在固定床系统中对Cs^(+)的吸附行为,包括柱床高、柱内径、进水流速和进水Cs^(+)浓度的影响。在最优固定床实验条件下,对比了SiO^(2)/Cu-PBA和阳离子交换树脂、在模拟地下水及模拟海水中保留Cs^(+)及其他共存碱金属及碱土金属离子(K^(+)、Na^(+)、Ca^(2+)和Mg^(2+))性能,结果表明,SiO_(2)/Cu-PBA拥有优异的Cs^(+)选择性和吸附性能,而树脂柱则在高盐分条件下失效。综上所述,SiO_(2)/Cu-PBA复合物在环境污染水体中选择性去除Cs^(+)方面具有很好的应用前景。

By using a column elution method,potassium copper ferrocyanide(Cu-PBA)was in situ loaded on silicon bead(SiO_(2))column packing,thereby yielding a SiO_(2)/Cu-PBA fixed bed column.The characterizations of SiO_(2)/Cu-PBA by SEM-EDS,FTIR,XRD and N_(2) adsorption-desorption isotherm techniques confirms the successful loading of Cu-PBA on SiO_(2).In batch experiments,it is found that the maximum adsorption capacity of SiO_(2)/Cu-PBA for Cs^(+)is around 4.0 mg/g,and it needs 30 min to reach equilibrium adsorption.Then,the adsorpion behavior of Cs^(+)by the SiO_(2)/Cu-PBA fixed bed was systematically studied,including the impacts of various operating parameters such as bed depth,bed diameter,flow rate,and influent Cs+concentration.In the optimized fixed bed system,the adsorption behaviors of Cs+and coexisting metal ions(K^(+),Na^(+),Ca^(2+),and Mg^(2+))by SiO_(2)/Cu-PBA and cation-exchanged resin were compared in both simulated groundwater and seawater.The efficient and highly selective removal of Cs^(+)by SiO_(2)/Cu-PBA is addressed as well as the inefficiency of cation-exchanged resin in simulated seawater.Therefore,the SiO_(2)/Cu-PBA composite will have great application prospects in the continuous removal of Cs^(+)from various Cs^(+)-contaminated environmental water media.