亚铁氰化锌对放射性废水中铜离子的吸附研究

Adsorption Study of Zinc Potassium Hexacyanoferrate for Copper Ion from Radioactive Wasterwater

采用共沉淀法制备了一种普鲁士蓝类似物——亚铁氰化锌（KZnFC），通过X射线荧光分析仪（XRF）和X射线衍射仪（XRD）表征分析，确定样品化学组成式为K1．11Zn1．53Fe（CN）6。采用静态吸附研究了亚铁氰化锌在不同吸附时间、用量、pH值、铜离子初始质量浓度条件下对模拟放射性废水硫酸铜溶液中铜离子的吸附影响，并通过透射电镜（TEM）和穆斯堡尔谱分析对吸附机理进行了初步探讨。实验结果表明：亚铁氰化锌对Cu外在用量为100mg、pH值为4～7、室温等条件下，2h内去除率可达89．23％，吸附量可达121．86mg／g。KZnFC对Cu2＋吸附前后的穆斯堡尔谱表明，此吸附过程主要是KZnFC中的K＋同溶液中Cu2＋进行离子交换反应。亚铁氰化锌对铜离子的吸附过程符合Freundlich吸附等温模型。

A Prussian blue analogue （KZnFC） was prepared by co-precipitation method. The compound was characterized using different techniques including X-ray fluorescence analyzer （XRF） and X-ray diffraction analyzer （XRD）. Results showed that the formula of the compound was K1.11Zn1. 53 Fe（CN）G. By static adsorption experiments, the effects of adsorption time, adsorbent dosage, pH, copper initial concentration on the adsorption properties of zinc potassium hexacyanoferrate for copper ion in simulating radioactive waste copper sulfate solution were studied. The adsorption mechanism was characterized by transmission electron microscopy （TEM） and Mossbauer spectrum. The experiment results showed that the removal of the K1. n Znl. 59 Fe（CN）6 for Cu2＋ can reach 89. 23% during 2 h , and the adsorption capacity can reach 121.86 mg/g in 100 mg dosage, 4-- 7 of pH and room temperature. Moreover, the Mossbauer measurements before and after adsorption of Cu2＋ showed that the Cu2＋ adsorption was mainly due to the ion exchange between K＋ in KZnFC and Cu2＋ in the solution. The adsorption of copper ion on zinc potassium hexacya- noferrate follows Freundlieh adsorption isotherm model.