Magnetic fusion reactors may use ceramic breeding blankets to generate tritium. A attractive method for recovering the tritium is to use about 1% H2 in He to sweep it out of the Tokamak. This mixture of hydrogen isotopes and He will need to be separated. An attractive method for this is cryogenic (liquid nitrogen temperature) adsorption. It has been shown that hydrogen will adsorb on such a material, leaving purified He leaving the bed. This method is well-suited for this application since the feed's major component is not adsorbed resulting in long times between regeneration and since the relatively large flowrates associated with this application can easily flow through an adsorbent-packed bed.

To properly design such an adsorber, equilibrium adsorption data is needed. Such data has been available for H2 and D2, but unavailable for T2. In this study isotherm data (bed loading versus partial pressure) were collected for 5A molecular sieve at liquid nitrogen temperatures. These data were collected by loading successive batches of a given isotope on the adsorbent and measuring the overpressure. It was found that T2 achieved the highest loading (cm3 (STP)/gm adsorbent) for a given partial pressure, followed by D2 and, lowest of all, H2. These data are compared to previous measurements. The data were modeled using appropriate isotherm equations.