241 Am in many soil samples should be analyzed,so that radioactive pollution level in nuclear facilities and its affinity environment can be surveyed efficiently.In this paper,in order to input the optimal conditions for column experiment,firstly,the experiments of adsorption coefficient of 241 Am to DGA resin under different contact time,concentration of HNO3 and different temperature were carried out.The chemical procedure for the rapid separation and determination of 241 Am in soils was formulated,which used DGA resin as extraction material and liquid scintillation spectrometry counting as measurement,EDTA solution as desorption mean.When the soil sample mass is 10 g,leached by 8 mol/L HNO3 , the chemical recovery of the procedure is about 95%,and the minimum detectable specific activity is 3.1 Bq/kg.Typically,a sample can be analyzed in 3 h.The presence of 137 Cs, 90 Sr-90 Y,239 Pu,99 Tc doesn't interfere with the procedure,owning high DF of them.The procedure can be used extensively.%为了对核设施及周边环境的放射性污染水平进行有效监测,需要对大量土壤样品中的241 Am进行分析.本工作首先考察了接触时间、介质酸度、温度对241 Am在DGA树脂柱上的吸附影响,确定了最佳吸附条件,为动态柱实验提供了输入条件;然后进行了动态柱实验的验证:以萃取色层法为分离纯化手段,采用高酸上柱,EDTA络合解吸,以低本底液闪谱仪为放射性测量手段,建立了一个快速分析土壤中241 Am的方法.当土壤样品量为10 g,使用8 mol/L HNO3浸取灰化后的模拟污染土壤样品,该方法对241 Am的化学回收率约为95%,最低可探测比活度为3.1 Bq/kg,全流程分析时间小于3 h.对其它核素137 Cs、90 Sr-90 Y、239 Pu、99 Tc有很好地去污能力.因此该方法可广泛应用于环境土壤样品的241 Am分析.
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