Hydrogen generated from hydrolysis of ammonia borane using cobalt and ruthenium based catalysts

Ammonia borane (NH3BH3, AB), one kind of promising hydrogen storage materials, is hydrolyzed to produce hydrogen in presence of HCl, Co/IR-120 and Ru/IR-120 catalysts. The kinetics analysis of the AB hydrolysis shows that hydrogen production is of the first-order reaction in regard to both concentrations of ammonia borane and catalysts initially present, respectively. The hydrolyzate of ammonia borane after hydrogen evolution is also characterized with XRD, FT-IR and B-11 NMR. Boric acid (H3BO3) is found to be the dominant product in the hydrolyzate. Besides, the produced gas is discovered to contain both hydrogen and ammonia according to the GC MS analysis and the indophenol colorimetric analysis. A possible reaction pathway on hydrogen generation from hydrolysis of ammonia borane is, accordingly, proposed based on the existence of boric acid, hydrogen and ammonia in the products. The total life cycle of ammonia borane is also proposed to illustrate formation of different intermediates during the AB hydrolysis for hydrogen generation and a possible regeneration scheme of the spent ammonia borane. Copyright (C) 2011, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.