Abstract: The present invention relates to the use of triborohydride salts as hydrogen storage materials. The present invention also relates to a system of using triborohydride salts to generate hydrogen gas for use in a fuel cell or other hydrogen-consuming device. A novel method of preparing triborohydride salts is also disclosed, wherein gaseous diborane is reacted with a carbonate suspended in a non-aqueous solvent in a suitable vessel with agitation. The process is typically carried out utilizing sodium carbonate to form sodium triborohydride. Other triborohydride salts can then be formed by cationic exchange. Hydrogen generating fuels according to the present invention include aqueous or hydroalcoholic solutions or slurries of a triborohydride salt, which may additionally contain a borohydride salt to provide operation over a broader temperature range.

Abstract: The present invention relates to an improvement in the recovery of boron values from a mixture of alkali metal borate and alkali metal hydroxide representing discharged fuel from a hydrogen generator apparatus. The mixture is reacted with carbon dioxide and a lower alcohol to form trialkyl borate, alkali bicarbonate and water. A porous water-absorbing material is added to the reaction mixture to absorb water as it forms thereby improving the yield of trialkyl borate. The trialkyl borate is converted to alkali borohydride that is used in the fuel.