US4437954A
Expired / Lapsed
US
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Fuels production by photoelectrolysis of water and photooxidation of soluble biomass materials
Assignee: Gas Technology Institute
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Filing: 1981-06-19
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Granted: 1984-03-20
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Expires: 2001-06-19
Abstract
Abstract A process and apparatus for production of fuels by photoelectrolysis of water and photooxidation of water soluble biomass and a process for preparation of Schottky-type metalized, appropriately doped n-type semiconductor photochemical diodes suitable for use in the above process and apparatus. The production of hydrogen by photoelectrolysis of water as the cathodic reaction of an optically illuminated photochemical diode is effected in an aqueous electrolyte which comprises a biomass product which may be monosaccharides, polysaccharides, lignins, their partially oxidized products, and mixtures thereof which are oxidized as the anodic reaction of the photochemical diode producing liquid fuels and useful chemicals. Molecular oxygen evolution is avoided and utilization of biomass product provides a cost effective material to increase fuels and useful chemical production by photoelectrolysis of water at potentials substantially less than required for normal water electrolysis involving oxygen evolution.
Inventors
- 👤 Anthony F. Sammells
- 👤 Michael R. St. John
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 02:48
CPC Classifications
H; H01; H01M; H01M8/00; H01M8/06; H01M8/0606; H01M8/0656; B; B01; B01J; B01J19/00; B01J19/08; B01J19/12; B01J19/122; C; C25; C25B; C25B1/00; C25B1/50; C25B1/55; Y; Y02; Y02E; Y02E60/00; Y02E60/30; Y02E60/36; Y02E60/50; Y10; Y10S; Y10S44/00; Y10S44/904
Claims Analysis
Total Claims: 33
Claim 1
Independent Claim
152 words
A process for fuels production by photoelectrolysis of water and photooxidation of water soluble biomass product avoiding molecular oxygen evolution comprising: passing an aqueous electrolyte comprising oxidizable biomass product selected from the group consisting of monosaccharides, polysaccharides, lignins, their partially oxidized products, and mixtures thereof in contact with both electrodes of a plurality of solid photochemical diodes of the type selected from the group consisting of Schottky-type metalized appropriately doped p-type semiconductor, Schottky-type metalized appropriately doped n-type semiconductors, appropriately doped p-n type semiconductors, and mixture thereof, said oxidizable biomass product oxidizing more cathodically than oxygen and having a decomposition potential more negative than said semiconductor; optically illuminating said semiconductor portion(s) of said photochemical diodes producing hydrogen as the cathodic reaction of said photochemical diode and producing oxidized biomass product as the anodic reaction of said photochemical diode; removing molecular hydrogen from said electrolyte; and separately removing oxidized biomass product from said electrolyte.
Claim 2
Dependent Claim
152 words
A process for fuels production by photoelectrolysis of water and photooxidation of water soluble biomass product avoiding molecular oxygen evolution comprising: passing an aqueous electrolyte comprising oxidizable biomass product selected from the group consisting of monosaccharides, polysaccharides, lignins, their partially oxidized products, and mixtures thereof in contact with both electrodes of a plurality of solid photochemical diodes of the type selected from the group consisting of Schottky-type metalized appropriately doped p-type semiconductor, Schottky-type metalized appropriately doped n-type semiconductors, appropriately doped p-n type semiconductors, and mixture thereof, said oxidizable biomass product oxidizing more cathodically than oxygen and having a decomposition potential more negative than said semiconductor; optically illuminating said semiconductor portion(s) of said photochemical diodes producing hydrogen as the cathodic reaction of said photochemical diode and producing oxidized biomass product as the anodic reaction of said photochemical diode; removing molecular hydrogen from said electrolyte; and separately removing oxidized biomass product from said electrolyte.
Claim 3
Dependent Claim
35 words
The process of claim 1 wherein said appropriately doped p-type semiconductor consists essentially of at least one p-doped material selected from the group consisting of Si, GaP, GaAs, InP, CuInS 2 and Cu 2 O.
Claim 4
Dependent Claim
57 words
The process of claim 1 wherein said appropriately doped n-type semiconductor consists essentially of at least one n-doped material selected from the group consisting of Si, CdS, TiO 2 , GaP, GaAs, CdSe, InP, MoS 2 , MoSe 2 , Fe 2 O 3 , CuInS 2 , WO 3 , CdWO 4 and ZnWO 4 .
Claim 5
Dependent Claim
14 words
The process of claim 1 wherein said optical illumination is provided by solar radiation.
Claim 6
Dependent Claim
11 words
The process of claim 1 wherein said biomass product comprises monosaccharide.
Claim 7
Dependent Claim
10 words
The process of claim 5 wherein said monosaccharide comprises glucose.
Claim 8
Dependent Claim
22 words
The process of claim 5 wherein said monosaccharide has a concentration of about 10 to about 600 grams/liter in said aqueous electrolyte.
Claim 9
Dependent Claim
16 words
The process of claim 7 wherein said monosaccharide concentration is about 100 to about 200 grams/liter.
Claim 10
Dependent Claim
11 words
The process of claim 1 wherein said biomass product comprises polysaccharide.
Claim 11
Dependent Claim
10 words
The process of claim 9 wherein said polysaccharide comprises starch.
Claim 12
Dependent Claim
10 words
The process of claim 9 wherein said polysaccharide comprises cellulose.
Claim 13
Dependent Claim
22 words
The process of claim 9 wherein said polysaccharide has a concentration of about 10 to about 600 grams/liter in said aqueous electrolyte.
Claim 14
Dependent Claim
16 words
The process of claim 9 wherein said polysaccharide concentration is about 100 to about 200 grams/liter.
Claim 15
Dependent Claim
11 words
The process of claim 1 wherein said biomass product comprises lignin.
Claim 16
Dependent Claim
22 words
The process of claim 14 wherein said lignin has a concentration of about 10 to about 600 grams/liter in said aqueous electrolyte.
Claim 17
Dependent Claim
16 words
The process of claim 15 wherein said lignin concentration is about 100 to about 200 grams/liter.
Claim 18
Dependent Claim
31 words
The process of claim 1 wherein said electrolyte is selected from the group consisting of aqueous acids, bases and inorganic salts providing ionic concentrations of about 0.05 to about 10 Molar.
Claim 19
Dependent Claim
20 words
The process of claim 17 wherein said acid is selected from the group consisting of hydrochloric, sulfuric, perchloric and phosphoric.
Claim 20
Dependent Claim
23 words
The process of claim 17 wherein said inorganic salt is selected from the group consisting of sodium chloride, potassium chloride and sodium sulfate.
Claim 21
Dependent Claim
20 words
The process of claim 17 wherein said base is selected from the group consisting of sodium hydroxide and potassium hydroxide.
Claim 22
Dependent Claim
17 words
The process of claim 17 wherein said electrolyte has a pH of about 4 to about 7.5.
Claim 23
Dependent Claim
18 words
The process of claim 1 wherein said electrolyte is maintained at temperatures about 65° to about 90° C.
Claim 24
Dependent Claim
28 words
The process of claim 1 wherein said diodes have an average particle size less than about 0.01 micrometer and form a solution of molecular-sized diodes in said electrolyte.
Claim 25
Dependent Claim
27 words
The process of claim 1 wherein said diodes have an average particle size about 0.1 to about 0.25 micrometer and form a colloidal suspension in said electrolyte.
Claim 26
Dependent Claim
26 words
The process of claim 1 wherein said diodes have an average particle size about 0.25 micrometer to about 1 millimeter and are suspended in said electrolyte.
Claim 27
Dependent Claim
26 words
The process of claim 1 wherein said diodes have an average particle size about 0.01 micrometer to about 1 millimeter and are suspended in said electrolyte.
Claim 28
Dependent Claim
29 words
The process of claim 26 wherein said diodes are in a concentration of about 0.1 to about 5 weight percent, based upon volume of said electrolyte being optically illuminated.
Claim 29
Dependent Claim
25 words
The process of claim 27 wherein said concentration is about 0.5 to about 1 weight percent, based upon volume of said electrolyte being optically illuminated.
Claim 30
Dependent Claim
29 words
The process of claim 1 wherein said diodes are in a concentration of about 0.1 to about 5 weight percent, based upon volume of said electrolyte being optically illuminated.
Claim 31
Dependent Claim
25 words
The process of claim 29 wherein said concentration is about 0.5 to about 1 weight percent, based upon volume of said electrolyte being optically illuminated.
Claim 32
Dependent Claim
18 words
The process of claim 1 wherein said doped semiconductor photochemical diodes have band gaps less than 2 eV.
Claim 33
Dependent Claim
18 words
The process of claim 1 wherein said diodes are Pt/n-TiO 2 Schottky-type metalized doped n-type semiconductor photochemical diodes.
References Cited (Backward Citations)
US4092129A
Cited
US4094751A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1987-03-20 | 1987-09-19 | 1988-03-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-03-20 | 1991-09-19 | 1992-03-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-03-20 | 1995-09-19 | 1996-03-20 | $7700.00 | Window Closed / Lapsed |