Kinetics Study of Solid Ammonia Borane Hydrogen Release – Modeling and Experimental Validation for Chemical Hydrogen Storage

Journal Article · Mon Feb 24 04:00:00 EST 2014 · Physical Chemistry Chemical Physics. PCCP, 16(17):7959-7968

DOI:https://doi.org/10.1039/C3CP55280B· OSTI ID:1132658

Choi, Yong-Joon; Ronnebro, Ewa; Rassat, Scot D.; Karkamkar, Abhijeet J.; Maupin, Gary D.; Holladay, Jamelyn D.; Simmons, Kevin L.; Brooks, Kriston P.

Ammonia borane (AB), NH3BH3, is a promising material for chemical hydrogen storage with 19.6 wt% gravimetric hydrogen capacity of which 16.2 wt% hydrogen can be utilized below 200°C. We have investigated the kinetics of hydrogen release from AB and from an AB-methyl cellulose (AB/MC) composite at temperatures of 160-300°C using both experiments and modeling. The purpose of our study was to show safe hydrogen release without thermal runaway effects and to validate system model kinetics. AB/MC released hydrogen at ~20°C lower than neat AB and at a rate that is two times faster. Based on the experimental results, the kinetics equations were revised to better represent the growth and nucleation process during decomposition of AB. We explored two different reactor concepts; Auger and fixed bed. The current Auger reactor concept turned out to not be appropriate, however, we demonstrated safe self-propagation of the hydrogen release reaction of solid AB/MC in a fixed bed reactor.

• Research Organization: Pacific Northwest National Laboratory (PNNL), Richland, WA (US), Environmental Molecular Sciences Laboratory (EMSL)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC05-76RL01830
• OSTI ID: 1132658
• Report Number(s): PNNL-SA-93992; 25661; HT0202000
• Journal Information: Physical Chemistry Chemical Physics. PCCP, 16(17):7959-7968, Journal Name: Physical Chemistry Chemical Physics. PCCP, 16(17):7959-7968
• Country of Publication: United States
• Language: English

Related Subjects

Environmental Molecular Sciences Laboratory
ammonia borane
hydrogen storage
kinetics
modeling