A simple method of recovery of I-131 from tellurium material using a tiny Dowex 1 column

Objectives One of the most important radionuclides that is used in nuclear medicine for treatment of thyroid gland cancer and imaging of thyroid is I-131. Radioiodines are generally produced from irradiated tellurium (Te), either as metallic Te or tellurium-di-oxide (TeO2). A new and simple wet method of separation of I-131 from TeO2 using a tiny Dowex 1 column was investigated and is reported here.

Methods An aliquot (1-2mCi) of I-131 was added to an alkaline solution of TeO2 (100mg) and the solution was passed through a tiny column of Dowex 1 resin (25mg). I-131 was retained on the column leaving Te in solution as waste. The column was washed with 0.1N NaOH and water. I-131 was eluted from column with 5ml tetrabutyl ammonium bromide (1mg) solution in methylene chloride. Methylene chloride was removed by heating under IR lamp and the residue was reconstituted with 0.1 N NaOH and filtered through 0.22um membrane filter. The quality control tests were performed with separated I-131 solution. Te was recovered from the waste solution by simple precipitation method at pH 5-6.

Results Recovery yield of Te was over 99%. Retention of I-131 on Dowex 1 resin column l was over 95%. Elution of I-131 from the column was over 90%. The R. C. Purity of I-131 after separation was >99%. The Te was not detected (chemical test).

Conclusions A simple method of separation of I-131 from Te material has been developed. This technique did generate no or little amount liquid radioactive waste as compared to the wet distillation technique where a large volume of radioactive and toxic waste generates