A study of tritium decontamination of deposits by UV irradiation

Abstract To develop a new method for decontamination of tritium retained in the carbon fiber composites (CFC) tiles and other components of D–T fusion reactors, a preliminary experiment using ultra violet (UV) light source was performed. Samples simulating a co-deposited layer were prepared by glow discharge using C 2 H 2 and a tungsten or CFC substrate. The UV light from a xenon excimer lump (172 nm) was irradiated to the samples in 423 K. Small amounts of species were released only by the heating procedure to 423 K. By UV irradiation, large quantities of hydrogen, carbon and hydrocarbons were released from the samples. Fourier Transform Infrared (FT-IR) analysis showed hydrocarbons were formed on the sample by acetylene glow discharge and C–H bonds were decomposed by irradiation with UV light. It is concluded that the combination of heating and UV irradiation causes release of tritium from the surface of the materials.