土壤样品中^(90)Sr和^(137)Cs浸取分析方法的研究

Study on the dissolution analysis method of 90Sr and 137Cs in soil samples

本文介绍了用四种不同的浸取剂,对土壤样品进行条件实验,结果表明,4mol/lHCl-0.4mol/lHF酸是土壤样品中^(90)Sr和^(137)Cs较为理想的浸取剂。用此混合酸浸取100g土壤样品中的^(90)Sr和^(137)Cs,借助经典方法分离纯化,对Ca、K的分离是完全的。示踪回收实验表明^(90)Sr、^(137)Cs的平均化学回收率和放化回收率基本一致。放化分析测得土壤中^(137)Cs平均浓度18.4Bq/kg,与γ谱仪测得结果18.0、18.5(Bq/kg)相吻合。对多种类型的近二百份土壤样品进行了^(90)Sr、^(137)Cs的分析,其化学回收率均大于80％。实际应用证明,土壤^(90)Sr、^(137)Cs联合浸取法切实可行,结果准确可靠。

A condition test on soil samples with four different dissolution preparations is presented. The results shbw that the 4 mol/l HC1-0.4 mol/1 HF is an ideal dissolvent for 90Sr and 137Cs in soil samples. With the mixed acid the nuclides 90Sr and 137Cs can be dissolved by the classical method. By radiochemical analysis; the average concentration of 137Cs in soil is 18.4 Bq/kg, well in agreement with the results of 18.0 and 18.5 Bq/kg determined by the gamma spectrometry method.The chemical recovery of 90Sr and J37Cs for about 200 soil samples is more than 80%. The procedure is accurate and reliable for practical use.