RI 폐기물 내 방사성요오드 분석을 위한 분리 및 회수

• 영문명: Separation and Recovery for the Analysis of Radioiodine in RI Wastes
• 발행기관: 한국방사성폐기물학회
• 저자명: 강상훈 한선호 이흥래 지광용 이인구
• 간행물 정보: 『Journal of Nuclear Fuel Cycle and Waste Technology (JNFCWT)』Vol.5 No.4, 267~272쪽, 전체 6쪽
• 주제분류: 공학 > 공학일반
• 파일형태: PDF
• 발행일자: 2007.12.31

국문 초록

RI 폐기물 내에 있는 낮은 방사능의 요오드의 함량을 결정하기 위해 산분해법과 HPGe 감마선분광계를 이용하는 방법이 개발되었다. 분석에 앞서 모의시료인 제염지 내에 131I이 일정량 첨가되었으며, 100 mL의 0.4 N K2Cr2O7와 100 mL의 9 M H2SO4, 10 mL의 30% H3PO3, 1 mL의 H2O2를 넣고 산분해과정을 거치면서 증류된 용액을 응축하여 포집하였다. CCl4의 용매추출에 의한 화학 분리과정을 거친 후 AgNO3를 첨가해서 얻은 AgI 침전물을 여과하고 건조하여 측정하였다. 산분해 과정, 화학 분리과정, 여과 및 침전과정 등 세 단계로 나눠 회수율을 측정한 결과, 각각 94 % 이상의 회수율을 나타냈으며, 본 연구의 측정조건에서 최소검출방사능은 0.16 ㏃/g이었다.

영문 초록

Various kinds of RI wastes are discharged from licensed organizations of radioisotopes such as hospitals and clinic organizations, educational organizations, research institutions, and public organizations. Radioiodines such as 125I and 131I are radioisotopes mainly used in nuclear medicine and industry. A method for the determination of radioiodines in RI wastes has been applied to measure low level activity using acid decomposition method and HPGe gamma ray spectrometer. Prior to analysis of real samples, 131I reference solution and 10 g of yellow tissue paper was added to flask in mantle and was heated in 100 mL of 0.4 N K2Cr2O7 and 100 mL of 9 M H2SO4, and then distilled after adding 10 mL of 30 % H2PO3 and 1 mL of 30 % H2O2. The condensed iodine by circulator was extracted into CCl4, then back-extracted into the aqueous phase with 10 mL of 5 % K2SO2 solution. Finally, 131I was measured at 364.48 keV using HPGe gamma ray spectrometer after precipitation and filtration. Chemical yield of three steps such as acid decomposition process, chemical separation process, and precipitation and filtration process was more than 94 % respectively. MDA(Minimum Detectable Activity) of 131I at this analytical condition was 0.16 ßq/g.

키워드

산분해법 방사성요오드 방사성동위원소 폐기물 Acid decomposition method Radioiodine RI waste