Removal of volatile radioactive iodine compounds from water vapor–air medium

Abstract

Sorption of CH₃¹³¹I and ¹³¹I₂ from water vapor–air medium onto SiO₂–C (2 wt %) composite material and a mixture of SKT-3I with SiO₂–Cu⁰ (10 wt %) was studied. SKT-3I shows high performance in sorption of ¹³¹I₂ and CH₃¹³¹I. The degree of localization of ¹³¹I₂ and CH₃¹³¹I exceeds 99.99% at ~60°С and gas phase–sorbent contact time τ of ~0.45 s. The degree of sorption of ¹³¹I₂ and CH₃¹³¹I onto the SiO₂–C (2 wt %) composite material under similar conditions does not exceed ~87 and ~8%, respectively. Experiments on ¹³¹I₂ and CH₃¹³¹I sorption onto mechanical mixtures of SiO₂–Cu⁰ and SKT-3I in the weight ratio varied from 1: 4 to 1: 1 showed that the degree of the ¹³¹I₂ and CH₃¹³¹I sorption at ~60°С and τ ~0.45 s exceeded 99.95 and 99.0%, respectively. The scheme of layer-by-layer arrangement of SiO₂–Cu⁰ and SKT-3I in the column was examined. It shows promise for use in AUI-1500VM filters in ventilation systems of nuclear power plants.