(259f) Hydrogen Release During Experimental Solid Sodium Borohydride Tablet Hydrolysis Reactions
AIChE Annual Meeting
2011
2011 Annual Meeting
International Congress on Energy 2011
Renewable Hydrogen Production I
Tuesday, October 18, 2011 - 10:35am to 11:00am
The objective of this research is to generate a step shape curve of the hydrogen release rate for PEMFCs used. The experiments use solid sodium borohydride and Ru/Al2O3 catalyst powder to compress and form the tablet. And using the fuel tablet as a reactant immerses it into the water and generates hydrogen. In order to achieve to step shape of hydrogen release rate, the operating variables of the system include the ratio of water/NaBH4 by weight, the ratio of catalyst/NaBH4 by weight and Surrounding Temperature(Ts). The result shows that hydrogen release rate is quite stable at 25ml/min when operating conditions are w/s=6, cat/s=0.015, and Ts=25°C, respectively. Up to here, we realize that heat removal rate is a key domain variable for sodium borohydride hydrolysis reaction. In order to obtain higher hydrogen release rate, the adiabatic operation is used to operate the system around 80°C. Finally, we propose a method to overcome the problems of the low hydrogen release rate and how to boost it, which is to initially apply heat to the hydrolysis system. The hydrogen release rate of the solid NaBH4 with an initial temperature of 70°C can reach 275ml/min without boost-up behavior.