The rate of an exchange reaction of hydrogen and deuterium in a Mg₂Ni bed

Hydrides of intermetallic compounds of Mg₂Ni have a comparatively large isotopic effect in the equilibrium isotherm between hydrogen and deuterium or tritium. An experimental and analytical study is made on the isotopic exchange reaction of hydrogen and deuterium in a Mg₂Ni bed for isotope separation. Values of the first moment, the second moment and a height equivalent to a theoretical plate (HETP) are obtained on the basis of a pulse or a step change of an influent deuterium concentration. It is found that the HETP values have the least at an optimum temperature and linear velocity, and the value is about 3 cm. The activation energy of the isotopic exchange reaction of Mg₂Ni is 18.5 kJ mol^-1. Thus the Mg₂Ni bed serves as an effective method for the isotopic separation of hydrogen isotopes.