TESTS ON ABSORBERS FOR IODINE AT LOW CONCENTRATIONS

A room (volume = 1,500 m/sup 3/) was used as the working volume in which low iodine concentrations for test purposes were generated. Various carbons, gas coke, copper and silver metal, wet scrubbers, filters, and double systems (absorber + filter) were tested for their iodine removal properties. Although the iodine concentration in the room decreased with time in each run, the exit concentration from the system under test was sensibly constant, and on this basis the various systems were compared. Carbon was the best absorber, and it was improved still further when combined with a filter. Gas coke and oxidized copper were unsatisfactory on account of their low absorption capacity. Iodine on copper was readily exchangeable, that on coke partially so, but that on carbon was not exchangeable. Part of the iodine released into the laboratory became attached to suspended particulate matter, and part was converted to a non- elemental vapor form. The latter fraction appeared to vary from run to run and its presence seemed to be the chief cause of the different performances of the various types of absorbers. (auth)