Investigations on the retention of iodine by sorbents in the case of fire

Investigations were performed on the influence of gaseous combustion products from four relevant materials used in NPPs on the retention of methyl iodide (CH3I--131) by four commercial impregnated activated carbons. The materials used to produce the combustion products were a PVC cable, a FRNC cable, a mineral oil and a paint. The carbons differed in base material (coal or coconut shell) and/or impregnant (KI or TEDA). The results show that with iodine filters of large bed depths and residence times (e.g. 25 cm and 0,5 s, respectively), when containing a usually employed impregnated activated carbon, a sufficiently high retention of iodine can be achieved even with a high challenge of gaseous combustion products from relevant materials used in NPPs. (orig./DG)