Transition metal catalysed dehydrogenation of amine-borane fuel blends

Abstract

Mixtures containing ammonia-borane and sec-butylamine-borane remain liquid throughout the hydrogen release process that affords tri(N-sec-butyl)borazine and polyborazylene. Concentrated solutions with metal catalysts afford >5 wt% H(2) in 1 h at 80 °C and addition of (EMIM)EtSO(4) ionic liquid co-solvent eliminates competing formation of insoluble linear poly(aminoborane) (EMIM = 1-ethyl-3-methyl-imidazolium).

Application of Ionic Liquids in Hydrogen Storage Systems

“…The most important are: hydrazine borane (HB), (Hugle et al, 2009) guanidinium borohydride (GBH), (Groshens & Hollins, 2009) ethylenediamine bisborane (EDB), (Neiner et al, 2011) methylguanidinium borohydride (Me-GBH) (Doroodian et al, 2010) and different alkyl amine boranes ( Figure 3). (Bowden et al, 2008;Mal et al, 2011) On the frontier between molecular and metal hydride storage materials are the metal amido borane compounds, which are not in the scope of this chapter. (Chua et al, 2011) A derivative of AB with a comparable weight efficiency has been studied by Lentz and coworkers recently: hydrazine borane (HB).…”

“…(Mal et al, 2011) The utilized mixture consisted of AB and sec-butyl amine borane (SBAB). The decomposition of this blend in the IL 1-ethyl-3-methylimidazolium ethyl sulfate ([EMIM][EtSO4]) leaves only a solution of products behind.…”

“…(Dupont & Suarez, 2006) Hydrogen-enriched materials or blends are as well in the focus of current research as catalytic decomposition. (Groshens & Hollins, 2009;Hugle et al, 2009;Jaska et al, 2003;Mal et al, 2011;Wright et al, 2011) ILs are investigated for their ability of supporting decomposition as well as solution of certain materials, including in some cases spent fuel products. (Bluhm et al, 2006;Wright et al, 2011) In some extent these approaches can be applied in combination.…”

Hydrogen storage in amine boranes: Ionic liquid supported thermal dehydrogenation of ethylene diamine bisborane

“…The decomposition of AB derivatives can circumvent this problem since nitrogen substituted derivatives of borazine as well as substituted amines are substantially less volatile. In this context methyl amine borane (MeAB) [19], sec-butyl amine borane (SBAB) [20], hydrazine borane (HB) [7] and ethylene diamine bisborane (EDB) have been investigated [5,6].…”

“…This approach was investigated in the blend of SBAB and AB in the IL ethylmethylimidazolium ethylsulfate ([EMIM] [EtSO 4 ]) by Baker and co-workers [20]. This liquid blend is able to release hydrogen in high purity, since the liberation of ammonia and borazine is prevented.…”