Comparison of Precious Metal Catalysts with Hydrophilic Porous Substrate for Tritium Cleanup System

Abstract

Existence of the structure water in the hydrophilic porous substrate can give various effects on tritium behavior in a tritium recovery system consisted of precious metal catalyst bed and adsorption bed because the catalytic isotope exchange reaction or the isotope exchange reaction proceeds besides oxidation reaction or adsorption reaction.

Properties of Pt catalysts loaded on various hydrophilic porous substrate are compared in this study. It is known from experiment that Pt-Alumina catalyst has the largest exchange capacity and that Pt-MS 5A catalyst has the largest total capacity because it has the effective adsorption capacity. For silica gel substrate, certain transport reaction of tritium in the substrate whose rate is rather slower than the rate of isotope exchange reaction is observed and it gives peculiar undesirable quality for silica gel to use in a tritium recovery system.

KEYWORDS:

• tritium
• tritiated water
• hydrophilic porous substrate
• precious metal catalyst bed
• platinum
• adsorption bed
• tritium recovery system
• structure water
• isotope exchange reaction