US4427508A
Expired / Lapsed
US
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Light driven photocatalytic process
Assignee: Atlantic Richfield Co
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Filing: 1982-05-03
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Granted: 1984-01-24
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Expires: 2002-05-03
Abstract
Abstract A method for the light driven photocatalytic reduction of carbon dioxide or the bicarbonate ion to one or more compounds which comprises contacting silicon with the carbon dioxide and/or bicarbonate ion in the absence of separate physical electrolyte and electrodes, and conducting said contacting in the presence of light.
Inventors
- 👤 Norman N. Lichtin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 14:08
CPC Classifications
C; C07; C07C; C07C51/00; B; B01; B01J; B01J19/00; B01J19/08; B01J19/12; B01J19/122; C01; C01B; C01B32/00; C01B32/40; C07C29/00; C07C29/15; C07C29/151; C07C29/153; C07C45/00
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
70 words
A method for the light driven photocatalytic reduction of carbon dioxide or the bicarbonate ion to at least one compound which comprises contacting silicon with a hydrogen containing material and at least one of carbon dioxide and the bicarbonate ion in the absence of separate physical electrolyte and electrodes, and conducting said contacting in the presence of light so that the energy of reduction is essentially supplied by said light.
Claim 2
Independent Claim
70 words
A method for the light driven photocatalytic reduction of carbon dioxide or the bicarbonate ion to at least one compound which comprises contacting silicon with a hydrogen containing material and at least one of carbon dioxide and the bicarbonate ion in the absence of separate physical electrolyte and electrodes, and conducting said contacting in the presence of light so that the energy of reduction is essentially supplied by said light.
Claim 3
Dependent Claim
19 words
The method according to claim 1 wherein said light is one of artificial light, sunlight, or a combination thereof.
Claim 4
Dependent Claim
28 words
The method according to claim 1 wherein said compounds are carbon monoxide, alcohols, aldehydes, hydrocarbons, esters, and carboxylic acids having from 1 to 2 carbon atoms per molecule.
Claim 5
Dependent Claim
13 words
The method according to claim 1 wherein said silicon is semiconductor grade silicon.
Claim 6
Dependent Claim
11 words
The method according to claim 4 wherein said silicon is p-silicon.
Claim 7
Dependent Claim
11 words
The method according to claim 4 wherein said silicon is n-silicon.
Claim 8
Dependent Claim
14 words
The method according to claim 1 wherein said silicon is not semiconductor grade silicon.
Claim 9
Dependent Claim
13 words
The method according to claim 7 wherein said silicon is metallurgical grade silicon.
Claim 10
Dependent Claim
13 words
The method according to claim 1 wherein said hydrogen containing material is water.
Claim 11
Dependent Claim
29 words
The method according to claim 9 wherein said silicon is dispersed in liquid water and said carbon dioxide and/or bicarbonate ion is carried to said silicon by said liquid.
Claim 12
Dependent Claim
13 words
The method according to claim 1 wherein said silicon is in subdivided form.
Claim 13
Dependent Claim
14 words
The method according to claim 11 wherein said silicon is subdivided into powder form.
Claim 14
Dependent Claim
49 words
The method according to claim 1 wherein said silicon is heat treated prior to contact with carbon dioxide or bicarbonate ion by heating at a temperature of from about 20° C. to about 600° C. for at least one hour in either air, an inert gas, or a vacuum.
Claim 15
Dependent Claim
24 words
The method according to claim 13 wherein said heat treatment is for from about 1 hour to about 48 hours in argon or air.
Claim 16
Dependent Claim
23 words
The method according to claim 13 wherein said heat treatment is for from about 1 hour to about 48 hours in a vacuum.
Claim 17
Dependent Claim
25 words
The method according to claim 1 wherein said light has a wavelength range such that at least part of said light is absorbed by silicon.
Claim 18
Dependent Claim
27 words
The method according to claim 1 wherein said at least one compound is selected from the group consisting of carbon monoxide, methanol, formaldehyde, formic acid, and methane.
Claim 19
Dependent Claim
12 words
The method according to claim 1 wherein said silicon is amorphous silicon.
Claim 20
Dependent Claim
13 words
The method according to claim 1 wherein said silicon is chemical grade silicon.
Claim 21
Dependent Claim
13 words
The method according to claim 1 wherein said hydrogen containing material is hydrogen.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-01-23 | 1987-07-25 | 1988-01-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-01-23 | 1991-07-25 | 1992-01-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-01-23 | 1995-07-25 | 1996-01-24 | $7700.00 | Window Closed / Lapsed |