Design of prototype reactor for hydrogen production from sodium borohydride

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2011

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Boran, Aslı

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Sodium borohydride (NaBH4) offers a simple and safe technology for storage and on demand production of hydrogen being a promising and a feasible method for fuel cell applications. The objectives of the present study are to emphasize the role of sodium borohydride as a part of future hydrogen energy system, to investigate the kinetics of the catalytic hydrolysis reaction of NaBH4 in a batch and flow system with respect to temperature, concentration, catalyst and flow rate for flow reactor by proposing a kinetic model and finally based on kinetic analysis, to design a prototype reactor to meet the hydrogen requirement for a 100W PEM fuel cell and operate it in steady state conditions. To express hydrolysis reaction by a kinetic model, series of batch experiments was performed in a glass flask (30mL) where the following parameters were systematically changed: the solution temperature varied as 20, 30 and 50°C, the NaBH4 concentration changed as 0.17, 0.23 and 0.3M, NaOH concentration varied as 0.27, 1.32 and 2.85M and catalyst amount was changed as 0.048, 0.07 and 0.1g Pt/C (ETEK®). In the kinetic model catalyst effect proposed within the rate constant. The kinetic model was purposed as: For flow reactor system, in a differential glass reactor (5mL) concentration, catalyst amount, catalyst type and flow rate was systematically analyzed at a constant temperature. For Pt/C catalyst the purposed model was: Also, for intrazeolite Co(0) nanoclusters, as a result of controlled experiments, the rate expression was found as: Based on these data prototype reactor (recycle) with internal volume of 122cm3 and storage volume of 1336 cm3 was designed, manufactured from Delrin® and operated.

Subject Keywords

Chemical engineering., Nuclear reactors

URI

http://etd.lib.metu.edu.tr/upload/12613639/index.pdf
https://hdl.handle.net/11511/20947

Collections

Graduate School of Natural and Applied Sciences, Thesis

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Citation Formats

A. Boran, “Design of prototype reactor for hydrogen production from sodium borohydride,” M.S. - Master of Science, Middle East Technical University, 2011.