摘要
根据亚钛还原钒酸铵滴定法的测定原理,对样品溶样、过滤洗涤、还原氧化、滴定等操作方法做了改进。磷酸-盐酸-过氧化氢混合酸低温溶解样品,离心分离过滤,亚钛还原UO22＋,过量亚钛用次溴酸钠氧化,尿素亚硝酸钠混合液进一步氧化未被次溴酸钠氧化的微量低价杂质。在小体积（10 mL）范围内,用低浓度钒酸铵标准溶液进行滴定操作测定微量铀,滴定终点清晰,相对标准偏差（RSD,n=5）为0.05%~0.07%,方法测定下限为0.001%,适于矿石和矿渣中0.001%~0.01%铀的测定。方法简便、快速,能满足生产和科研的需要。
Based on the titrimetry with reduction of ammonium vanadate by titanous chloride for the determination of micro-amount of uranium,some operation procedures in sample digestion,filtration and washing,reduction-oxidation and titration were improved.Samples were digested with H3PO4-HCl-H2O2 at low temperature.After centrifugation,filtering,reduction of UO2＋2 with Ti3＋,oxidization of excessive Ti3＋ by NaBrO3 and further oxidization of trace impurities with low valence by urea-NaNO3,uranium in the sample solution in a small volume（10 mL） was titrated with ammonium vanadate.The end point of the titration was very clear.Detection limit of the method for uranium was 0.001% and precision was 0.05%~ 0.07%RSD.The method provides the advantages of simple operation,high efficiency and is suitable for the determination of 0.001%～0.01% uranium in ore and slag samples.
出处
《岩矿测试》
CAS
CSCD
北大核心
2010年第3期325-327,共3页
Rock and Mineral Analysis
基金
江西省教育厅重点科技项目资助--相山铀矿开采区稻谷中天然放射性核素铀
钍含量研究(GJJ09023)
关键词
亚钛
钒酸铵
滴定法
微量铀
矿石
titanous chloride
ammonium vanadate
titrimetry
micro-amount of uranium
ore
