A study of tritium decontamination of deposits by UV irradiation

To develop a new method for decontamination of tritium retained in the carb on fiber composites (CFC) tiles and other components of D-T fusion reactors , a preliminary experiment using ultra violet (UV) light source was perform ed. Samples simulating a co-deposited layer were prepared by glow discharge using C2H2 and a tungsten or CFC substrate. The UV light from a xenon exci mer lump (172 MI) was irradiated to the samples in 423 K. Small amounts of species were released only by the heating procedure to 423 K. By UV irradia tion, large quantities of hydrogen, carbon and hydrocarbons were released f rom the samples. Fourier Transform Infrared (FT-IR) analysis showed hydroca rbons were formed on the sample by acetylene glow discharge and C-H bonds w ere decomposed by irradiation with UV light. It is concluded that the combi nation of heating and UV irradiation causes release of tritium from the sur face of the materials. (C) 2001 Elsevier Science B.V. All rights reserved.