The tritium bred in a deuterium-tritium fusion reactor is to be extracted from the tritium breeding blanket by sweep gas. To be used as fuel for the reactor, the tritium must be recovered in a form that is easy to transfer to the main fuel cycle. The feasibility of a cryosorption method that uses a porous adsorbent, such as molecular sieves or activated carbon, at liquid nitrogen temperature (77.4 K) is discussed.