固相萃取α能谱法快速测定环境样品中铀放射性核素

Rapid Determination of Uranium Radionuclides in Environmental Samples by Solid Phase Extraction Alphaspectrometry Method

为了对环境中放射性污染水平进行有效监测,需要对环境样品中铀放射性核素进行分析。本实验采用浓硝酸溶液加热浸取样品中的铀,UTEVA树脂对铀进行吸附并用稀盐酸溶液进行解吸,有机物TTA萃取制成α测量源,通过示踪剂铀-232的计数来校正铀(铀-234、铀-235和铀-238)的化学回收率。本方法实现了对环境样品中铀放射性核素的快速分析,同时进行了条件实验,确定了最佳测量条件:浸取液为8.0 mol/L硝酸溶液,解吸液为0.01 mol/L盐酸溶液,示踪剂用量为180 mBq。结果表明,当样品用量为0.5 g,测量时间100000 s时,该方法的最小可探测活度浓度为0.13 Bq/kg,满足环境样品中铀放射性核素的分析要求。

Uranium radionuclides in environmental samples should be analyzed to survey radioactive pollution.In this paper,the uranium in the samples was extracted by heating with concentrated nitric acid solution,adsorbed by UTEVA resin and desorbed by dilute hydrochloric acid solution.The measurement source was extracted by TTA and chemical recovery of uranium(U-234,U-235 and U-238)was corrected by tracer U-232.The method realized the rapid analysis of uranium radionuclides in environmental samples,and the condition experiments were carried out to determine the optimal measurement conditions:the extracting solution was 8.0 mol/L nitric acid solution,the desorption solution was 0.01 mol/L hydrochloric acid solution,and the dosage of tracer was 180 mBq.When the amount of sample is 0.5 g and the measurement time is 10000 s,the minimum detectable activity concentration of the method is 0.13 Bq/kg,which meet the requirement of radionuclides analysis in environmental samples.