Granulated rhodium catalysts of sodium borohydride hydrolysis for generators of high-purity hydrogen

Abstract

Sodium borohydride hydrolysis in a flow reactor with turbulent mixing of reactants in a catalytic bed by the evolving hydrogen bubbles was studied. The stability of catalytic systems decreases in the order 1% Rh/Sibunit > 1% Rh/TiO₂ > 1% Rh/γ-Al₂O₃. The decrease in the hydrogen generation rate is caused by the formation of a metaborate film on the catalyst surface, by the loss of the active component, and by disintegration of support granules and their removal with the flow of the spent liquid. High granule strength and macroporous structure of 1% Rh/Sibunit ensure stable generation of hydrogen.