US4330301A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Dispersant for aqueous slurry of coal powder
Assignee: Kao Corp
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Filing: 1980-07-03
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Granted: 1982-05-18
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Expires: 2000-07-03
Abstract
Abstract A dispersant for forming an aqueous slurry of coal powder having a good flowability, which comprises as the active ingredient at least one member selected from sulfonation products of polycyclic aromatic compounds which may have a hydrocarbon group as a substituent, salts thereof and formaldehyde condensates thereof.
Inventors
- 👤 Masaaki Yamamura
- 👤 Noboru Moriyama
- 👤 Shin-ichi Watanabe
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 00:26
CPC Classifications
C; C10; C10L; C10L1/00; C10L1/32; C10L1/326; C09; C09K; C09K23/00; C09K23/12
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
68 words
An aqueous slurry consisting essentially of from 30 to 85% by weight of powdered coal, from 0.01 to 5.0% by weight of dispersant for dispersing said powdered coal in water, said dispersant being a formaldehyde condensate of sulfonated naphthalene material selected from the group consisting of naphthalene sulfonic acid, alkylnaphthalene sulfonic acid, alkenylnaphthalene sulfonic acid, salts of said acids and mixtures thereof, and the balance is essentially water.
Claim 2
Dependent Claim
68 words
An aqueous slurry consisting essentially of from 30 to 85% by weight of powdered coal, from 0.01 to 5.0% by weight of dispersant for dispersing said powdered coal in water, said dispersant being a formaldehyde condensate of sulfonated naphthalene material selected from the group consisting of naphthalene sulfonic acid, alkylnaphthalene sulfonic acid, alkenylnaphthalene sulfonic acid, salts of said acids and mixtures thereof, and the balance is essentially water.
Claim 3
Dependent Claim
35 words
An aqueous slurry as claimed in claim 1 consisting essentially of from 50 to 75% by weight of powdered coal, from 0.05 to 2.0% by weight of said dispersant, and the balance is essentially water.
Claim 4
Dependent Claim
39 words
An aqueous slurry as claimed in claim 1 in which said alkylnaphthalene sulfonic acid has up to 6 carbon atoms in the alkyl substituent and said alkenylnaphthalene sulfonic acid has up to 6 carbon atoms in the alkenyl substituent.
Claim 5
Dependent Claim
22 words
An aqueous slurry as claimed in claim 1 in which the degree of condensation of said condensate is from 1.2 to 30.
Claim 6
Dependent Claim
22 words
An aqueous slurry as claimed in claim 1 in which the degree of condensation of said condensate is from 1.2 to 10.
Claim 7
Dependent Claim
35 words
An aqueous slurry as claimed in claim 5 in which said dispersant is a formaldehyde condensate of alkylnaphthalene sulfonic acid or salt thereof in which the alkyl group contains from 1 to 6 carbon atoms.
Claim 8
Dependent Claim
36 words
An aqueous slurry as claimed in claim 1 in which said salts of said acids are selected from the group consisting of sodium salts, potassium salts, calcium salts, amine salts and ammonium salts of said acids.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1985-05-17 | 1985-11-16 | 1986-05-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-05-17 | 1989-11-16 | 1990-05-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-05-17 | 1993-11-16 | 1994-05-18 | $7700.00 | Window Closed / Lapsed |