Novel Catalysts for Isotopic Exchange between Hydrogen and Liquid Water

Abstract

Catalytic isotopic exchange between hydrogen and liquid water offers many inherent potential advantages for the separation of hydrogen isotopes which is of great importance in the Canadian nuclear program. Active catalysts for isotopic exchange between hydrogen and water vapour have long been available, but these catalysts are essentially inactive in the presence of liquid water. New water repellent platinum catalysts have been prepared by: 1) treating supported catalysts with silicone, 2) depositing platinum on inherently hydrophobic polymeric supports, and 3) treating platinized carbon with Teflon and bonding to a carrier. The activity of these catalysts for isotopic exchange between counter-current streams of liquid water and hydrogen saturated with water vapour has been measured in a packed trickle bed integral reactor. The performance of these hydrophobic catalysts is compared with nonwetproofed catalysts. The mechanism of the overall exchange reaction is briefly discussed. 6 figures, 1 table.