Process for the exchange of hydrogen isotopes using a catalyst packed bed assembly

Claim 1

A process for the exchange of hydrogen isotopes using a catalyst bed assembly, comprising: a. simultaneously contacting streams of liquid water and hydrogen with one another and a catalyst packed bed assembly in the path of the contacting streams, both of said streams being at a temperature in the range 273° to 573° K., with one of the streams containing a concentration of a hydrogen isotope in excess of that which it would contain when the liquid water-gaseous hydrogen streams are in isotopic equilibrium at the operating conditions of temperature and mass flow rates of the streams and the other stream being a deficient stream and containing a concentration of that hydrogen isotope which is less than that which it would contain when the liquid water gaseous hydrogen is in equilibrium at said operating conditions, so that the deficient stream is enriched by transfer of the hydrogen isotope in a two-step hydrogen isotope exchange process from the other stream with the following simultaneous reactions being closely coupled in space ##EQU5## b. recovering the said stream enriched in the hydrogen isotope, and wherein: c. the catalyst packed bed assembly comprises: i. a catalyst structure comprising at least one carrier, catalyst crystallites of at least one catalytically active metal selected from Group VIII of the Periodic Table on the support, and a water repellent, water vapour and hydrogen gas permeable, porous, polymeric material partially enclosing the catalyst crystallites to substantially inhibit the contact of liquid water with the catalyst crystallites while allowing contact therewith of hydrogen gas and water vapour from the liquid water, and ii. a packing structure interspersed with (i) to form therewith the catalyst packed bed assembly across the whole path of the contacting streams, and having an exterior surface which is substantially hydrophilic and relatively noncatalytically active with regard to hydrogen isotope exchange between hydrogen gas and water vapour to that of the catalyst bodies, so that: d. the hydrogen isotope exchange primarily occurs simultaneously between hydrogen gas and water vapour contacting the catalyst crystallites, and between water vapour contacting the liquid water and that liquid water, and the substantially hydrophilic exterior surface of the packing structure increases the contact surface area between the water vapour and liquid water thereby increasing the rate of hydrogen isotope exchange between water vapour and liquid water.