The removal of gaseous elemental iodine from the vapor stream entering an ice condenser unit was studied for the effects of vapor composition, ice additives, ice loading, vapor temperature, flow channels, flow characteristics, and iodine concentration. It was found that alkaline additives enhance the retention of iodine in the ice melt by hydrolysis reactions which convert the iodine to nonvolatile, soluble forms of iodide and iodate. The effect of the iodine content in the steam-air mixtures at the levels studied was found to be small. The iodine removal was strongly influenced by the fraction of air in the steam-air vapor mixture. Several tests using methyl iodide instead of elemental iodine indicated that the ice would not be an efficient means for removal of organic halides.