摘要：

制备了膨润土负载纳米铁铜双金属复合材料（FeCu/BT），用SEM、EDS、FTIR、XRD、XPS进行表征并分析铀去除机理，考察了pH、投加量、初始浓度、离子干扰等因素对水溶液中铀去除效果的影响。结果表明，在pH为7、投加量为4 g/L、反应时间为60 min、初始铀质量浓度为10 mg/L时，铀去除率达到95.5%。共存离子PO₄^3-对去除效率的影响最大，SO₄^2-、NO₃^-几乎无影响。FeCu/BT除铀过程的吸附动力学符合准二级动力学模型，以化学吸附为主；等温吸附模型符合Freundlich等温吸附模型，为非均一多分子层吸附。FeCu/BT除铀过程主要为吸附、还原、络合作用，Cu起到催化、固定和吸附的作用。

关键词: 绿色合成, 膨润土, 纳米铁铜, 含铀废水

Abstract:

Bentonite-supported nano-iron-copper bimetal material(FeCu/BT) was prepared, characterized by SEM, EDS, FTIR, XRD, and XPS, and its uranium removal mechanism was analyzed. The uranium removal from aqueous solutions at different pH, dosage, initial concentration, and ion interference conditions were studied. Experiments showed that the removal rate of uranium reached 95.5% at the conditions of pH=7, the dosage 4 g/L, the reaction time 60 min, and the initial uranium mass concentration 10 mg/L. Co-existing ion PO₄^3- had the most negative effect on reaction, meanwhile that SO₄^2- and NO₃^- almost had no effect. The adsorption kinetics of uranium removal by FeCu/BT was well fitted with pseudo-second-order model and dominated by chemical adsorption. And the isothermal adsorption conformed to Freundlich model, which was heterogeneous multilayer adsorption. The process of uranium removal mainly included adsorption, reduction, complexation, and Cu played the role of catalysis, fixation and adsorption.

Key words: green synthesis, bentonite, nano-iron-copper, wastewater containing uranium

中图分类号: 

• X703