PTFE Dispersed hydrophobic catalysts for hydrogen—water isotopic exchange: I. Preparation and characterization

Abstract

The development of a catalyst that is not inactivated when submerged in water is likely to be important in the exploitation of the isotopic hydrogen—water exchange process for the production and detritiation of heavy water. Using a method based on radiation-induced polymerization of adsorbed tetrafluoroethene monomer, we have successfully deposited a thin (ca. 0.1 μm) and uniform polytetrafluoroethene (PTFE) film on different substrates, such as activated charcoal, zeolites and alumina. Catalysts prepared by dispersing platinum metal over these substrates were found to have a longer life when used for hydrogen—[ 2H]water isotopic exchange under 100% humidity conditions than those prepared from uncoated supports or when PTFE was physically blended with the support. The catalysts were characterized using scanning electron microscopy, X-ray diffraction, differential scanning calorimetry and Auger electron spectroscopy.