Tritium isotope separation by water distillation column packed with silica-gel beads

Tritium enrichment or depletion by water distillation was investigated using a glass column of 32 cm in height packed with silica-gel beads of 3.4mm in average diameter. The total separation factor of the silica-gel distillation column, α_H-T—, was compared with those of an open column distillation tower and of a column packed with stainless-steel Dixon rings. Depletion of the tritium activity in the distillate was enhanced by isotopic exchange with water adsorbed on silica-gel beads that have a higher affinity for HTO than for H₂O. The value of alpha_H-T-1 of the silica-gel distillation column was about four times larger than that of a column without any packing and about two times larger than that of the Dixon-ring column. The improvement of α_H-T by the silica-gel adsorbent indicated that the height of the distillation-adsorption column becomes shorter than that of the height of conventional distillation columns.