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CaBr 2 HYDROLYSIS FOR HBr PRODUCTION USING A DIRECT SPARGING CONTACTOR
• Use of low-temperature steam at 473 K (200°C) as a reagent is practical in a molten-phase
hydrolysis reactor. What is significant about this is that the process engineering will need to
focus only on the heat exchange to main a low-pressure melt (i.e. CaBr 2 -CaO) at the design
reaction temperature of 1 050 K (777°C).
• The observed kinetic constant is 24 times greater than the constant reported for solid CaBr 2
reaction. This higher rate promises to significantly reduce the size and design complexity of
the hydrolysis reactor.
The comparison of the kinetic constants between various experimentalists needs to be reviewed,
recognising that there is evidence for a complex being formed. The novel method investigated here
for sparging steam into a molten calcium bromide bath to form HBr with no apparent side-products
suggests a path forward for thermochemical hydrogen production cycles, with both technical and
engineering advantages.
Acknowledgements
This effort was sponsored by the US Department of Energy (DOE) Nuclear Energy Research Initiative.
The investigations described herein were conducted by Argonne National Laboratory under DOE
contract no. DE-AC02-06CH11357. The kind assistance of Professor Miroslav Boča, Institute of Inorganic
Chemistry, Slovak Academy of Sciences (Bratislava, Slovakia) is gratefully acknowledged.
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