US3984225A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Soil conditioners and fertilizers from spent sulfite liquor
Assignee: International Telephone and Telegraph Corp
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Filing: 1974-08-19
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Granted: 1976-10-05
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Expires: 1994-08-19
Abstract
Abstract Spent sulfite liquor is converted into a nitrogen containing, water insoluble product useful as a soil conditioner and as a slow-release fertilizer. The spent sulfite liquor is reacted at a temperature of from 170° to 250°C with hexamethylenetetramine or with an ammonia-formaldehyde mixture. The weight ratio of hexamethylenetetramine or ammonia and formaldehyde to SSL solids should be greater than about 0.5:1 and preferably greater than 1:1.
Inventors
- 👤 Karl David Sears
- 👤 Franklin Willard Herrick
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 05:12
CPC Classifications
C; C05; C05C; C05C3/00; Y; Y02; Y02P; Y02P60/00; Y02P60/20; Y02P60/21; Y10; Y10S; Y10S71/00; Y10S71/903
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
58 words
A process for preparing a nitrogen containing, water insoluble product consisting essentially of reacting in the absence of oxygen as a reactant spent sulfite liquor at a temperature from 170° to 250°C with a reactant selected from the group consisting of hexamethylenetetramine and ammonia:formaldehyde mixtures, over 94% of the total nitrogen of said reaction product being organically bound.
Claim 2
Dependent Claim
58 words
A process for preparing a nitrogen containing, water insoluble product consisting essentially of reacting in the absence of oxygen as a reactant spent sulfite liquor at a temperature from 170° to 250°C with a reactant selected from the group consisting of hexamethylenetetramine and ammonia:formaldehyde mixtures, over 94% of the total nitrogen of said reaction product being organically bound.
Claim 3
Dependent Claim
11 words
The process of claim 1 in which the reactant is hexamethylenetetramine.
Claim 4
Dependent Claim
16 words
The process of claim 1 in which the reactant is a mixture of ammonia and formaldehyde.
Claim 5
Dependent Claim
19 words
The process of claim 1 in which the reaction is carried out for from 15 minutes to 3 hours.
Claim 6
Dependent Claim
20 words
The process of claim 1 in which the weight ratio of reactant to spent sulfite liquor is greater than 0.5:1.
Claim 7
Dependent Claim
16 words
The process of claim 1 in which the temperature of reaction is from 200° to 230°C.
Claim 8
Dependent Claim
13 words
The process of claim 1 in which the spent sulfite liquor is ammonia-base.
Claim 9
Dependent Claim
13 words
The process of claim 1 in which the spent sulfite liquor is sodium-base.
Claim 10
Dependent Claim
15 words
The process of claim 3 in which the ratio of ammonia:formaldehyde is 0.5:1 to 2:1.
Claim 11
Dependent Claim
8 words
The product of the process of claim 1.
References Cited (Backward Citations)
US2279200A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-10-05 | 1980-04-05 | 1980-10-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-10-05 | 1984-04-05 | 1984-10-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-10-05 | 1988-04-05 | 1988-10-05 | $7700.00 | Window Closed / Lapsed |