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US3990904A
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Method for the preparation of xylose solutions
Assignee: Sued Chemie AG
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Filing: 1976-05-11
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Granted: 1976-11-09
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Expires: 1996-05-11
Abstract
Abstract A method for the preparation of xylose solutions from oat husks which comprises: A. hydrolyzing oat husks with a solution of alkali metal hydroxide to provide oat husks from which the chemically bound acetic acid originally present therein has been substantially completely removed, and a solution of acetic acid, provided, that a quantity of not less than one mole, and not more than two moles, of said solution of alkali metal hydroxide is used per mole of acetic acid originally present in the oat husks; B. recovering the oat husks from which the chemically bound acetic acid has been substantially removed; and C. hydrolyzing the oat husks of step (b) with a mineral acid to provide a solid residue containing lignin and an acidic solution of D-(+)-xylose.
Inventors
- 👤 Hermann Friese
- 👤 Hans Buckl
- 👤 Bernd Brenner
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 04:00
CPC Classifications
C; C13; C13K; C13K13/00; C13K13/002
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
127 words
A method for the preparation of xylose solutions from oat husks which comprises: a. hydrolyzing oat husks with a solution of alkali metal hydroxide to provide oat husks from which the chemically bound acetic acid originally present therein has been substantially completely removed, and a solution of acetic acid, provided, that a quantity of not less than one mole, and not more than two moles, of said solution of alkali metal hydroxide is used per mole of acetic acid originally present in the oat husks; b. recovering the oat husks from which the chemically bound acetic acid has been substantially removed; and c. hydrolyzing the oat husks of step (b) with a mineral acid to provide a solid residue containing lignin and an acidic solution of D-(+)-xylose.
Claim 2
Independent Claim
127 words
A method for the preparation of xylose solutions from oat husks which comprises: a. hydrolyzing oat husks with a solution of alkali metal hydroxide to provide oat husks from which the chemically bound acetic acid originally present therein has been substantially completely removed, and a solution of acetic acid, provided, that a quantity of not less than one mole, and not more than two moles, of said solution of alkali metal hydroxide is used per mole of acetic acid originally present in the oat husks; b. recovering the oat husks from which the chemically bound acetic acid has been substantially removed; and c. hydrolyzing the oat husks of step (b) with a mineral acid to provide a solid residue containing lignin and an acidic solution of D-(+)-xylose.
Claim 3
Dependent Claim
23 words
The method of claim 1 wherein the D-(+)-xylose present in the acidic solution of step (c) is recovered therefrom in substantially pure form.
Claim 4
Dependent Claim
36 words
The method of claim 1 wherein hydrolysis step (a) is carried out with a solution containing from 1.1 to 1.2 moles of alkali metal hydroxide per mole of acetic acid orginally present in the oat husks.
Claim 5
Dependent Claim
23 words
The method of claim 1 wherein hydrolysis step (a) is carried out with a solution of sodium hydroxide, potassium hydroxide or combination thereof.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-11-09 | 1980-05-10 | 1980-11-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-11-09 | 1984-05-10 | 1984-11-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-11-09 | 1988-05-10 | 1988-11-09 | $7700.00 | Window Closed / Lapsed |