Solid compositions which generate hydrogen by combustion, comprising an alkali metal borohydride or alkaline earth metal borohydride and an oxidizing salt based on ammonium perchlorate, alkali metal perchlorate or alkaline earth metal perchlorate

• US 20040065865A1
• Filed: 09/05/2003
• Published: 04/08/2004
• Est. Priority Date: 10/04/2002
• Status: Active Grant

• Current Assignee: ArianeGroup SAS
• Original Assignee: SNPE
• Inventors: Renouard, Joel, Perut, Christian, Desgardin, Nancy
• Granted Patent: US 7,094,487 B2
• Time in Patent Office: Days
• US Class Current: 252/188.25
• CPC Class Codes: C01B 3/065 from a hydride
• CPC Class Codes: C06B 47/10 a component containing free boron, an organic borane or a binary compound of boron, except with oxygen
• CPC Class Codes: C06D 5/06 by reaction of two or more solids
• CPC Class Codes: H01M 8/065 by dissolution of metals or alloys; by dehydriding metallic substances
• CPC Class Codes: Y02E 60/36 Hydrogen production from non-carbon containing sources, e.g. by water electrolysis
• CPC Class Codes: Y02E 60/50 Fuel cells

Abstract

The invention relates to a solid composition which can decompose with the generation of hydrogen according to a self-sustaining combustion reaction after initiation of this reaction by an appropriate heat source, this composition being characterized in that it comprises an alkali metal borohydride or alkaline earth metal borohydride and a perchlorate-based oxidizing salt corresponding to the general formula XClO₄ in which X represents the NH₄ group, an alkali metal or an alkaline earth metal.

Claims

1. Solid composition which can decompose with the generation of hydrogen according to a self-sustaining combustion reaction after initiation of this reaction by an appropriate heat source, characterized in that the said composition comprises an alkali metal borohydride or alkaline earth metal borohydride and a perchlorate-based oxidizing salt corresponding to the general formula XClO₄ in which X represents the NH₄ group, an alkali metal or an alkaline earth metal.

2. Solid composition according to claim 1, characterized in that X represents sodium or potassium.

3. Solid composition according to claim 1, characterized in that it is provided in the form of a compact material.

4. Solid composition according to claim 3, characterized in that the compact material is a pellet or a grain.

5. Solid composition according to claim 1, characterized in that it is devoid of organic matter.

6. Solid composition according to claim 1, characterized in that it is composed essentially of alkali metal borohydride or alkaline earth metal borohydride and of the perchlorate-based oxidizing salt of general formula XClO₄.

7. Solid composition according to claim 1, characterized in that the sum of the contents by weight of alkali metal borohydride or alkaline earth metal borohydride and of oxidizing salt of general formula XClO₄ is greater than or equal to 90% with respect to the total weight of the composition.

8. Solid composition according to claim 1, characterized in that the alkali metal borohydride is chosen from the group consisting of lithium borohydride, sodium borohydride and their mixtures.

9. Solid composition according to claim 1, characterized in that the alkaline earth metal borohydride is magnesium borohydride.

10. Solid composition according to claim 1, characterized in that the ratio of content by weight of alkali metal borohydride or alkaline earth metal borohydride to content by weight of oxidizing salt XClO₄ is between 1 and 10.

12. Hydrogen generator intended to supply hydrogen to a proton exchange membrane fuel cell, characterized in that this generator is a pyrotechnic generator comprising a solid composition according to claim 1.

13. Proton exchange membrane fuel cell using hydrogen as fuel, comprising at least one electrochemical cell (1) and one hydrogen generator connected to the anode compartment of the cell (1), characterized in that this hydrogen generator is a pyrotechnic generator according to claim 12.

11. Process for the generation of hydrogen by self-sustaining combustion of a solid composition comprising an alkali metal borohydride or alkaline earth metal borohydride and a perchlorate-based oxidizing salt, characterized in that:

a pulverulent or granular homogeneous solid composition comprising an alkali metal borohydride or alkaline earth metal borohydride and a perchlorate-based oxidizing salt of general formula XClO₄ in which X represents an NH₄ group, an alkali metal or an alkaline earth metal is prepared,

this composition is subsequently agglomerated using appropriate means, so as to form a compact material,

the compact material is placed in a combustion chamber,

the combustion of the compact material is initiated using an appropriate heat source, which brings about the self-sustaining combustion of the material with generation of hydrogen up to the end of the combustion.