Evaluation of methods for retention of radioiodine during processing of irradiated 237Np

Methods of removing radioiodine from 237Np--238Pu dissolver solution and process off-gas were investigated. This program is part of a continuing effort to reduce releases of radionuclides from plant operations. Experimental data show: Greater than 99.9 percent of the radioiodine in dissolver solution can be removed by precipitation, in situ, of manganese dioxide. Silver zeolite will sorb greater than 99.9 percent of radioiodine in process off-gas. Other solid sorbents and nitric acid-mercuric nitrate scrubber solutions do not remove appreciable amounts of radioiodine from process off-gas, because radioiodine is present principally as relatively unreactive organic iodine compounds. (U.S.)