Dehydrogenation Pressure Drop in NaBH₄ Solution in Ru-Catalyzed 300 μm Microchannel Chemical Reactor

Abstract:

Sodium borohydride (NaBH₄) is considered to be a secure metal hydride for hydrogen storage and supply. In this study, the two-phase pressure drop in the dehydrogenation of aqueous NaBH₄ solution in a microchannel with a hydraulic diameter of 300 μm is investigated for the purpose of designing a dehydrogenation chemical reactor. Because hydrogen gas was generated by the hydrolysis of NaBH₄ in the presence of a ruthenium catalyst, two different phases of flow (aqueous NaBH₄ solution and hydrogen gas) exist in the microchannel reactor. For experimental studies, a microchannel was fabricated on a silicon wafer substrate with a 100 nm ruthenium catalyst deposited on three sides of the channel surface. Based on the experimental result, it is found that the two-phase multiplier linearly increases with the void fraction, which depends on the initial NaBH₄ concentration, the NaBH₄ reaction rate, and the flow residential time.

• Periodical: Applied Mechanics and Materials (Volume 420)
• Pages: 240-245
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.420.240
• Online since: September 2013
• Authors: Hee Joon Lee
• Keywords: Chemical Reactor, Dehydrogenation, Micro-Channel, Pressure Drop, Sodium Borohydride

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