Adiabatic multi-stage reactors for hydrogen production and related systems and methods

A system, comprising:

• an ammonia gas source;
• a heater;
• a plurality of reactor systems comprising first and second reactor systems, each reactor system comprising:
• a reactor comprising:
• a housing defining an internal space;
• a first inlet in fluid communication with the internal space of the housing;
• a first outlet in fluid communication with the internal space of the housing;
• an ammonia cracking catalyst disposed in the internal space of the housing;
• a plurality of hollow fibers within the internal space, each of the hollow fibers defining an interior and comprising a hydrogen-permeable membrane;
• and
• a second inlet and a second outlet that are each in fluid communication with the interiors of the plurality of hollow fibers,
• wherein, for each reactor system, the internal space of the housing that is in fluid communication with the first inlet and the first outlet is a space that is external to a space occupied by the plurality of hollow fibers;
• wherein the system is configured so that during use of the system:
• the ammonia gas source provides a first gas stream comprising ammonia;
• the heater heats the first gas stream to provide a heated first gas stream comprising heated ammonia;
• the heated first gas stream is introduced into the internal space of the first reactor via the first inlet of the first reactor where a portion of the heated ammonia is converted to hydrogen;
• a second gas stream comprising ammonia exits the first reactor via the first outlet of the first reactor;
• a portion of the first gas stream is configured to be combined with the second gas stream;
• the heater heats the second gas stream to provide a heated second gas stream comprising heated ammonia;
• and
• the heated second gas stream is introduced into the internal space of the second reactor via the first inlet of the second reactor where a portion of the heated ammonia is converted to hydrogen.