The IRL has implemented a method of complex radiochemical analysis of radioactive isotopes. The method was applied for plutonium ( 238Pu, 239,240Pu, 241Pu), strontium (90Sr), americium ( 241Am) isotopes in samples of soil, bottom sediments, aerosol filters, and radioactive waste of nuclear plants. The method provides a possibility to isolate the abovementioned isotopes from one sample.
The best results of the IAEA research to this end were taken as a basis.
The IRL has updated the method in the process of its implementation. The laboratory experts managed to additionally isolate uranium ( 234U, 235U, 238U) isotopes plus to the abovementioned ones.
Performance of such complex and labor intensive comprehensive analysis is only possible with high-tech equipment and highly qualified staff available and special techniques applied. The method shall expand the IRL possibilities in the area of analyzing radioactive isotopes contents in environmental samples as well as in samples of radioactive waste, foodstuff, etc. It may be used for the purposes of radiological control at nuclear fuel facilities, also for radiation monitoring implemented by SES, the Ministry of Health of Ukraine; by scientific institutions performing radiological research.
The following main stages are envisaged by the method:
- microwave separation of samples (this significantly, tenfold, reduces the time of analysis if compared to wet (acid) incineration);
- separation of isotopes at strong ion-exchange resins;
- preparation of isolated isotopes’ targets by methods of electrodeposition and codeposition at micro membranes;
- measurement of the prepared targets’ activity at alpha- and beta-spectrometers, liquid scintillation counter.
The method was tested on a standard soil sample (Soil-6, IAEA). The satisfactory results were obtained for a precision of measured activities of the abovementioned isotopes and IAEA-certified activity values for Soil-6 sample.