US4748235A
Expired / Lapsed
US
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Method of producing improved amine salts of lignosulfonates
Assignee: WESTVACO Corp 299 PARK AVENUE NEW YORK NEW YORK 10171 A CORP OF DE
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Filing: 1987-04-16
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Granted: 1988-05-31
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Expires: 2007-04-16
Abstract
Abstract A method of producing an amine-containing salt of a sulfonated lignin compound which may be effectively spray-dried for use in dry form comprising the steps of methylolating a lignin at an alkaline pH, lowering the pH of the methylolated lignin to precipitate the lignin, washing the precipitated lignin at an acid pH to remove impurities, sulfonating the methylolated lignin in the presence of a sulfur-oxygen-containing compound, an amine compound, and ammonium hydroxide and/or ammonium sulfite or bisulfite to produce an amine/ammonium salt thereof, and heating and spray-drying the sulfonated lignin amine/ammonium salt to effectively evaporate ammonia therefrom to produce the sulfonated lignin amine-containing salt in dry form.
Inventors
- 👤 Peter Dilling
- 👤 Susan L. Schlegel
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 22:52
CPC Classifications
C; C09; C09B; C09B67/00; C09B67/0071; C09B67/0084; C09B67/0085; C09B67/0086
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
107 words
A method of producing an amine-containing salt of a lignosulfonate compound which may be effectively spray-dried for use in dry form comprising the steps of (a) methylolating a lignin compound at an alkaline pH; (b) lowering the pH of the methylolated lignin to precipitate the lignin; (c) washing the precipitated lignin at an acid pH to remove impurities; (d) sulfonating the methylolated lignin in the presence of a sulfur-oxygen-containing compound, an amine compound, and an ammonium-containing compound to produce an amine salt thereof; and (e) heating and spray-drying the sulfonated lignin amine salt while evaporating ammonia therefrom to produce a sulfonated lignin amine salt in dry form.
Claim 2
Independent Claim
107 words
A method of producing an amine-containing salt of a lignosulfonate compound which may be effectively spray-dried for use in dry form comprising the steps of (a) methylolating a lignin compound at an alkaline pH; (b) lowering the pH of the methylolated lignin to precipitate the lignin; (c) washing the precipitated lignin at an acid pH to remove impurities; (d) sulfonating the methylolated lignin in the presence of a sulfur-oxygen-containing compound, an amine compound, and an ammonium-containing compound to produce an amine salt thereof; and (e) heating and spray-drying the sulfonated lignin amine salt while evaporating ammonia therefrom to produce a sulfonated lignin amine salt in dry form.
Claim 3
Dependent Claim
49 words
A method as defined in claim 1 wherein the methylolated lignin is sulfonated at a pH of above 6, and the moles of amine compound present in the sulfonation reaction are equal to or less than 1.25 times the moles of sulfur dioxide present, plus 0.5 moles amine compound.
Claim 4
Dependent Claim
26 words
A method as defined in claim 2 wherein the amine compound is triethanolamine, the sulfur-oxygen-containing compound is sulfur dioxide, and the ammonium-containing compound is ammonium hydroxide.
Claim 5
Dependent Claim
18 words
A method as defined in claim 2 wherein the sulfur-oxygen-containing compound and the ammonium-containing compound is ammonium bisulfite.
Claim 6
Dependent Claim
26 words
A method as defined in claim 1 wherein the amine compound is triethanolamine, the sulfur-oxygen-containing compound is sulfur dioxide, and the ammonium-containing compound is ammonium hydroxide.
Claim 7
Dependent Claim
18 words
A method as defined in claim 1 wherein the sulfur-oxygen-containing compound and the ammonium-containing compound is ammonium bisulfite.
References Cited (Backward Citations)
US3407188A
Cited
US3505243A
Cited
US4047567A
Cited
US4444562A
Cited
US4590262A
Cited
US4636224A
Cited
US4642336A
Cited
US4629469A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-05-31 | 1991-11-30 | 1992-05-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-05-31 | 1995-11-30 | 1996-05-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-05-31 | 1999-11-30 | 2000-05-31 | $7700.00 | Window Closed / Lapsed |