A hybrid thermochemical electrolytic process for hydrogen production based on the reverse deacon reaction

Researchers at Argonne National Laboratory have initiated development of a relatively simple three-step, hybrid thermochemical-electrolytic process for converting water into hydrogen with heat from a nuclear reactor. One of the valuable aspects of this process relative to most other hydrogen-producing cycles is that it can be run at 500°C, making it suitable to several nuclear reactor heat source concepts. Furthermore, the lower temperatures make the materials requirements for this hydrogen process less stringent than for high temperature cycles, many of which require temperatures upwards of 800-900°C. This process consists of three reactions - two thermochemical and one electrolytic. The thermochemical reactions sum to the Reverse Deacon Reaction. The electrolytic step is anhydrous HCI electrolysis. The estimated energy savings for this process relative to water electrolysis is in the vicinity of 20%. largely due to the relatively favorable thermodynamics of anhydrous HCI electrolysis. Preliminary experimental results indicate that using a silicalite-supported catalyst for the Reverse Deacon Reaction has the potential of promoting fast reaction kinetics and long-term stability of the solids.