Stabilized aluminum hydride polymorphs

• US 6,617,064 B2
• Filed: 03/29/2001
• Issued: 09/09/2003
• Est. Priority Date: 06/16/1999
• Status: Expired due to Term

• Current Assignee: Ardica Technologies Incorporated
• Original Assignee: SRI International, Inc.
• Inventors: Bottaro, Jeffrey C., Schmitt, Robert J., Penwell, Paul E., Bomberger, David C., Petrie, Mark A.
• Primary Examiner(s): Langel, Wayne A.
• Application Number:
  US09/823,379
• Publication Number:
  US 20010038821A1
• Time in Patent Office: 894 Days
• Field of Search: 423/645, 423/265, 423/274, 429/12, 429/206, 149/37, 149/43, 149/46, 149/61, 149/109.4, 526/159, 568/881, 568/885, 585/250
• US Class Current: 429/421
• CPC Class Codes: C01B 6/06 Hydrides of aluminium, gallium, indium, thallium, germanium, tin, lead, arsenic, antimony, bismuth or polonium; Monoborane; Diborane; Addition complexes thereof
• CPC Class Codes: C06B 45/10 the organic component containing a resin
• CPC Class Codes: H01M 4/242 Hydrogen storage electrodes
• CPC Class Codes: H01M 8/065 by dissolution of metals or alloys; by dehydriding metallic substances
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y02E 60/50 Fuel cells

Abstract

The present invention features methods for preparing stabilized α-AlH₃ and α′-AlH₃, compositions containing these alane polymorphs, e.g., energetic compositions such as rocket propellants, and methods for using the novel polymorphs as chemical reducing agents, polymerization catalysts, and as a hydrogen source in fuel cells and batteries. The method produces stabilized alane by treating α-AlH₃ with an acidic solution that optionally contains a stabilizing agent such as an electron donor, an electron acceptor, or a compound which coordinates the Al³⁺ ion.

Claims

1. A stabilized α

-AlH₃ product prepared by the process comprising;

(a) reacting an alkali metal hydride with AlCl₃ in a solution of diethyl ether to form an initial AlH₃ product in a reaction mixture, along with an alkali metal chloride;

(b) removing the alkali metal chloride from the reaction mixture by filtration;

(c) adding an excess of toluene to the filtrate resulting from step (b), providing a diethyl ether-toluene solution;

(d) heating and distilling the diethyl ether-toluene solution to reduce the amount of diethyl ether in the solution, until a precipitate is formed;

(e) isolating the precipitate;

(f) adding the precipitate to an acidic solution effective to dissolve and thus remove materials other than α

-AlH₃; and

(g) isolating α

-AlH₃ from the acidic solution,

wherein the acidic solution contains an α

-AlH₃ stabilizing agent comprised of a compound that coordinates to an Al³⁺ ion.

2. The stabilized α

-AlH₃ product of claim 1, wherein the α

-AlH₃ stabilizing agent is aurintricarboxylic acid triammonium salt.

3. The stabilized α

-AlH₃ product of claim 1, wherein the α

-AlH₃ stabilizing agent is 8-hydroxyquinoline.

4. The stabilized α

-AlH₃ product of claim 1, wherein the α

-AlH₃ stabilizing agent is catechol.

5. The stabilized α

-AlH₃ product of claim 1 wherein the α

-AlH₃ stabilizing agent further comprises an electron donor or an electron acceptor.

6. The stabilized α

-AlH₃ product of claim 5, wherein the electron donor or electron acceptor is selected from the group consisting of tetrachlorobenzoquinone, diphenylamine, tetracyanoethylene, 7,7,8,8-tetracyanoquinodimethane, tetrathiafulvalene and tetrakis(dimethylamino)ethylene.

7. In a propellant composition comprising a fuel, a binder, and an oxidizer, the improvement comprising using as the fuel the stabilized α

-AlH₃ product of any one of claims 1, 2, 3, 4, 5 or 6.

8. In a method for reducing a functional group in a molecule by reaction with a reducing agent comprising a hydride donor, the improvement comprising using as the hydride donor the stabilized α

-AlH₃ product of any one of claims 1, 2, 3, 4, 5 or 6.

9. In a method for conducting a reaction comprising the polymerization of monomers using a polymerization catalyst comprising a hydride donor, the improvement comprising using as the hydride donor the stabilized α

-AlH₃ product of any one of claims 1, 2, 3, 4, 5 or 6.

10. In an alkaline storage battery comprising a positive electrode, a negative electrode comprised of a hydrogen storage material, and an aqueous alkaline electrolyte, the improvement comprising using as the hydrogen storage material the stabilized α

-AlH₃ product of any one of claims 1, 2, 3, 4, 5 or 6.

11. In a fuel cell for continuously delivering electricity, comprising a contained hydrogen source as a fuel, and an oxidant, the improvement which comprises using as said hydrogen source the stabilized α

-AlH₃ product of any one of claims 1, 2, 3, 4, 5 or 6.