摘要
ThO_(2)经加速器轰击后可以产生多种核素,如^(225)Ac、^(223)Ra、^(99)Mo、^(131)I、^(90)Sr等。钍等重元素的测量方法众多,但大多操作复杂。分光光度法具有制样简单、操作难度小的优点,可作为钍等重元素的定量分析手段。采用HNO_(3)/HF体系对ThO_(2)进行溶解,以偶氮胂Ⅲ为显色剂定量分析ThO_(2)溶解液中Th(Ⅳ)的浓度。在2 mol/L盐酸溶液和0.1 g/L偶氮胂Ⅲ溶液的环境下,确定了在本法所确定的实验条件下偶氮胂Ⅲ与Th(Ⅳ)的配位比为5∶2,显色前后的最大吸收波长分别为534.0 nm和663.2 nm,对比度为129.2 nm。该方法在0.2~5.0 mg/L符合朗伯-比尔定律,标准曲线方程为y=0.06641x+0.00176,R^(2)=0.99981,摩尔吸光系数为1.64×10^(4),方法检出限为0.31μg/L,定量限为0.97μg/L。该方法在4 h以内稳定,回收率为97.33%~104.03%,最大标准偏差为0.32%。本方法与GB/T 12690.12-2003相比,流程简化且测定结果基本一致。
ThO_(2)can produce many nuclides after accelerator bombardment,such as Actinium-225,Radium-223,Molybdenum-99,Iodine-131,Strontium-90,etc.There are many methods for measuring heavy elements such as thorium,but most of them are complicated to operate.Spectrophotometry has the advantages of simple sample preparation and low operation difficulty,and can be used as a quantitative analysis method for thorium and other heavy elements.ThO_(2)was dissolved with nitric acid and hydrogen fluoride,and the concentration of Th(Ⅳ)in ThO_(2)solution was quantitatively analyzed with ArsenazoⅢas the chromogenic agent.Under the environment of 2 mol/L hydrochloric acid solution and 0.1 g/L ArsenazoⅢsolution,the coordination ratio of ArsenazoⅢand Th(Ⅳ)is 5:2 under the experimental conditions.The maximum absorption wavelength before and after color development is 534.0 nm and 663.2 nm,respectively,and the contrast is 129.2 nm.The method in 0.2-5.0 mg/L is in accordance with Lambert-Beer’s law,the standard curve equation y=0.06641x+0.00176,R^(2)=0.99981.The molar absorption coefficient of 1.64×10^(4).Method detection limit is 0.31μg/L,and quantitative limit is 0.97μg/L.The method is stable within 4 h.The recovery is 97.33%-104.03%,and the largest standard deviation is 0.32%.The method was compared with GB/T 12690.12-2003,the process was simplified and the results were basically consistent.
作者
赵鹏飞
吴久伟
王宇
李勇
官国英
ZHAO Pengfei;WU Jiuwei;WANG Yu;LI Yong;GUAN Guoying(Department of nuclear technology and application,China Institute of Atomic Energy,Beijing 102413,China)
出处
《同位素》
CAS
2024年第2期146-152,共7页
Journal of Isotopes
基金
中国原子能科学研究院青年英才培育项目(YC222412001304)。
关键词
偶氮胂Ⅲ
二氧化钍
定量分析
arsenazo Ⅲ
thorium dioxide
quantitative analysis
