Hydrogen generator

• US 20040120889A1
• Filed: 11/05/2003
• Published: 06/24/2004
• Est. Priority Date: 11/05/2002
• Status: Active Grant

• Current Assignee: Protonex Technology Corporation (Honeywell International Inc.)
• Original Assignee: Millennium Cell Inc.
• Inventors: Kelly, Michael T., Shah, Shailesh A.
• Granted Patent: US 7,323,148 B2
• Time in Patent Office: Days
• US Class Current: 423/657
• CPC Class Codes: B01D 2313/42 Catalysts within the flow path
• CPC Class Codes: B01D 63/02 Hollow fibre modules
• CPC Class Codes: B01D 69/08 Hollow fibre membranes manufacture of hollow fibres D01D5/24, D01F1/08
• CPC Class Codes: B01J 19/0053 Details of the reactor
• CPC Class Codes: B01J 19/2475 Membrane reactors
• CPC Class Codes: B01J 19/2485 Monolithic reactors
• CPC Class Codes: C01B 2203/041 In-situ membrane purification during hydrogen production
• CPC Class Codes: C01B 2203/0465 Composition of the impurity
• CPC Class Codes: C01B 2203/047 the impurity being carbon monoxide
• CPC Class Codes: C01B 2203/066 with fuel cells
• CPC Class Codes: C01B 3/065 from a hydride
• CPC Class Codes: C01B 3/501 by diffusion
• CPC Class Codes: Y02E 60/32 Hydrogen storage
• CPC Class Codes: Y02E 60/36 Hydrogen production from non-carbon containing sources, e.g. by water electrolysis

Abstract

A hydrogen generator capable of operating in any orientation and having no moving parts includes a catalyst retaining structure. The catalyst retaining structure is disposed in a housing and serves to separate the housing into a fuel holding portion and a hydrogen chamber. The catalyst retaining structure also includes one or more pores, each pore being in communication with the fuel holding and hydrogen chambers. A catalyst, that promotes the generation of hydrogen gas upon contact with the fuel, is disposed within the pores. The fuel enters the pores and thereupon generates hydrogen gas which passes into the hydrogen chamber. Contact of the fuel with the catalyst in the pores may be controlled and the position of the fuel-hydrogen interface within the pore may be moved so as to regulate the generation of hydrogen. The catalyst retaining structure can take different forms, including one or more hollow elongated members or plates, and may further incorporate hydrophobic and/or hydrophilic membranes.

Claims

1. A hydrogen gas generation system comprising;

(a) a housing; and

(b) a member which separates said housing into a fuel holding chamber and a hydrogen chamber, said member having a first surface facing the fuel holding chamber and a second surface facing the hydrogen chamber,

c) a fuel solution in said fuel holding chamber, and

d) said fuel holding chamber being structured to permit fuel solution movement without capillary action to said first surface, said member having at least one pore formed therein which communicates with said first and said second surfaces, said pore also having a catalyst disposed therein which promotes the generation of hydrogen upon contact with the fuel solution, said pore being dimensioned so that fuel in said fuel chamber moves into the pore and contacts the catalyst, and the generated hydrogen produced thereby passes into said hydrogen chamber.

2. The hydrogen gas generation system as defined in claim 1 wherein said at least one pore is dimensioned to inhibit fuel solution from passing from the fuel holding chamber to the hydrogen chamber.

3. The hydrogen gas generation system as defined in claim 1 wherein the member is fabricated of a material and the pore has a cross section, the cross section at any position being a function of the fuel solution and the material.

4. The hydrogen gas generation system as defined in claim 3 wherein the pore has a varying cross-section.

5. The hydrogen gas generation system as defined in claim 3 wherein said at least one pore is dimensioned based upon the following equation:

P_cr=2γ

cos θ

/r_p

where P_cr is the break through pressure;

γ

is the interfacial tension between the 2 phases (fuel solution and hydrogen) in the pore, θ

is the contact angle measured from the pore wall to the tangent of the 2 phase interface drawn from the three phase contact point at the pore wall into the pore fluid and rp is the pore radius.

6. The hydrogen gas generation system as defined in claim 1 wherein said at least one pore comprises a plurality of individual pores oriented generally parallel to each other.

7. The hydrogen gas generation system as defined in claim 1 wherein said first exterior surface is hydrophilic.

8. The hydrogen gas generation system as defined in claim 1 wherein said second exterior surface is hydrophobic.

9. The hydrogen gas generation system as defined in claim 1 wherein said first exterior surface is hydrophilic and second exterior surface is hydrophobic.

10. The hydrogen gas generation system as defined in claim 1 wherein the first exterior surface and the second exterior surface are hydrophobic.

11. The hydrogen gas generation system as defined in claim 1 wherein said housing comprises a structure capable of raising the pressure within the fuel holding chamber.

12. The hydrogen gas generation system as defined in claim 11 wherein the structure capable of raising the pressure within the fuel holding chamber comprises a movable wall of said fuel holding chamber adapted to be moved inwardly exert a force against the fuel solution within said fuel holding chamber.

13. The hydrogen gas generation system as defined in claim 12 wherein said movable wall comprises a spring biased plate.

14. The hydrogen gas generation system as defined in claim 1 wherein the pore has a conical cross-section.

15. The hydrogen gas generation system as defined in claim 1 wherein the member comprises a hollow fiber.

16. The hydrogen gas generation system as defined in claim 1 wherein the member comprises at least one set of flat plates, each having pores formed therein.

17. The hydrogen gas generation system as defined in claim 16 wherein each of the at least one set of flat plates comprises hydrophilic plate, a catalyst containing plate having pores containing the catalyst, and a hydrophobic sheet held together.

18. A method of generating hydrogen gas comprising:

providing a housing having a member separating the housing into a fuel holding chamber with a fuel solution disposed therein and a hydrogen chamber, the member having a first exterior surface facing the fuel storage chamber and a second exterior member facing the hydrogen chamber, the member having at least one pore communicating with the first and second exterior surface and having a catalyst disposed therein that promotes the generation of hydrogen upon contact with said fuel solution, said fuel solution in said fuel holding chamber being capable of moving to said first exterior surface without capillary action; and

allowing said fuel solution to enter into said pore and contact said catalyst so as to generate hydrogen.

19. A hydrogen gas generation system comprising;

(a) a housing; and

(b) a member which separates said housing into a fuel holding chamber and a hydrogen chamber, said member having a first surface facing the fuel holding chamber and a second surface facing the hydrogen generation chamber,

c) a fuel solution in said fuel holding chamber, and

d) said fuel holding chamber being structured to permit fuel solution movement to said first surface without the use of wicking material, said member having at least one pore formed therein which communicates with said first and said second surfaces, said pore also having a catalyst disposed therein which promotes the generation of hydrogen upon contact with the fuel solution, said pore being dimensioned so that fuel in said fuel chamber moves into the pore and contacts the catalyst, and the generated hydrogen produced thereby passes into said hydrogen generation chamber.

20. A method of generating hydrogen gas comprising:

providing a housing having a member separating the housing into a fuel holding chamber with a fuel solution disposed therein and a hydrogen chamber, the member having a first exterior surface facing the fuel storage chamber and a second exterior surface facing the hydrogen chamber, the member having at least one pore communicating with the first and second exterior surface and having a catalyst disposed therein that promotes the generation of hydrogen upon contact with said fuel solution, said fuel solution in said fuel holding chamber being capable of moving to said first exterior surface without capillary action; and

allowing said fuel solution to enter into said pore and contact said catalyst so as to generate hydrogen.

21. A method for producing a catalyst retaining structure comprising:

providing a member having a first exterior surface and a second exterior surface, the member having at least one pore communicating with the first and second exterior surface; and

flowing a solution containing at least one transition metal ion in contact with said first exterior surface; and

flowing a reducing agent solution in contact with said second exterior surface; and

allowing said solution containing at least one transition metal ion and said reducing agent solution to enter into said pore and contact each other in order to deposit catalyst particles on the wall of said pore.

22. A method according to claim 21, wherein said transition metal is selected from the group of ruthenium, cobalt, nickel, palladium, platinum, molybdenum, manganese, iron, chromium, and zinc.

23. A method according to claim 22, wherein said reducing agent is a chemical hydride.

24. A method for producing a catalyst retaining structure comprising:

providing a member having a first exterior surface and a second exterior surface, the member having at least one pore communicating with the first and second exterior surface; and

flowing a solution containing at least one transition metal ion in contact with said first exterior surface;

flowing hydrogen gas in contact with said second exterior surface; and

allowing said solution containing at least one transition metal ion and hydrogen gas to enter into said pore and contact each other in order to deposit catalyst particles on the wall of said pore.

25. A method according to claim 24, wherein said transition metal is selected from the group of ruthenium, cobalt, nickel, palladium, platinum, molybdenum, manganese, iron, chromium, and zinc.