Patent US2616894A successfully refreshed from Google Patents.
EP0047641A2
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EP
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Ethanol production by high performance bacterial fermentation
Assignee: George Weston Ltd
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Filing: 1981-09-04
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Granted: —
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Expires: 2001-09-04
Abstract
Abstract The present invention is directed to the preparation of ethanol by bacterial fermentation. It makes use of a microorganism capable of producing ethanol and the process is carried out in two stages. In the first stage a bacterial cell suspension is produced together with ethanol in an ethanol concentration range that does not substantially inhibit production of the bacterial cells in a medium containing a source of nitrogen and a source of carbon. Ethanol is then produced in the absence of substantial bacterial cell production by the addition of fermentable sugar to the bacterial cell suspension which is produced in the first stage. The preferred microorganism is a member of the genus Zymomonas.
Inventors
- 👤 Hugh Gibson Lawford
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-31 06:54
CPC Classifications
C; C12; C12P; C12P7/00; C12P7/02; C12P7/04; C12P7/06; C12P7/065; Y; Y02; Y02E; Y02E50/00; Y02E50/10
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
83 words
A process for producing ethanol by fermentation, which comprises culturing a microorganism, capable of producing ethanol, in two stages comprising (i) producing a bacterial cell suspension together with ethanol in an ethanol concentration range that does not substantially inhibit production of the bacterial cells in a medium containing a source of nitrogen and a source of carbon, and (ii) producing ethanol in the absence of substantial bacterial cell production by the addition of fermentable sugar to the bacterial cell suspension produced in (i).
Claim 2
Dependent Claim
83 words
A process for producing ethanol by fermentation, which comprises culturing a microorganism, capable of producing ethanol, in two stages comprising (i) producing a bacterial cell suspension together with ethanol in an ethanol concentration range that does not substantially inhibit production of the bacterial cells in a medium containing a source of nitrogen and a source of carbon, and (ii) producing ethanol in the absence of substantial bacterial cell production by the addition of fermentable sugar to the bacterial cell suspension produced in (i).
Claim 3
Dependent Claim
17 words
A process as claimed in claim 1, wherein the said microorganism is a member of the.genus Zymomonas.
Claim 4
Dependent Claim
44 words
A process as claimed in claim 1 or claim 2 wherein the bacterial cells are produced in a mineral salt medium containing NH 4 + ions as the sole source of nitrogen or in such a medium supplemented with an organic source of nitrogen.
Claim 5
Dependent Claim
39 words
A process as claimed in claim 1, claim 2 or claim 3, wherein bacterial cell and ethanol production are conducted under anaerobic conditions within a pH range of 4 to 8 and a temperature range of 20 - 40°C.
Claim 6
Dependent Claim
40 words
The process claimed in any one of the preceding claims. wherein the carbon source for bacterial cell and ethanol production is glucose, fructose or sucrose, any mixture of these sugars or.a polysaccharide hydrolysate containing one or more of these sugars.
Claim 7
Dependent Claim
35 words
The process of any one of the preceding claims, wherein the two stages of the process are conducted in the same fermenter by continuous addition of the fermentable sugar after termination of bacterial cell production.
Claim 8
Dependent Claim
38 words
A process as claimed in any one of claims 1 to 5 wherein the two stages of the process are conducted in the same fermenter by intermittent addition of the fermentable sugar after termination of bacterial cell production.
Claim 9
Dependent Claim
41 words
The process of claim 6 or claim 7, wherein the bacterial cells are collected at the end of the second stage of the process and resuspended in a fermentable sugar solution . and the bacterial cells are returned to stage (ii).
Claim 10
Dependent Claim
64 words
The process of any one of claims 1 to 5, wherein the two stages of the process are conducted in two fermenters with the bacterial cells produced by continuous culture in the first fermenter being continuously transferred to a second constant volume fermenter which permits the complete utilization of a continuous feed of the fermentable sugar required for the second stage of the process.
Claim 11
Dependent Claim
30 words
The process of claim 9, wherein a portion of the bacterial cells from the second'fermenter are removed from the effluent by continuous filtration or sedimentation and returned to stage (ii).
References Cited (Backward Citations)
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