US4328002A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Methods of treating coal to remove sulfur and ash
Assignee: ROBERT BENDER ASSOCIATES Inc C/O JOSEPH A KATARINCIC ESQ
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Filing: 1981-06-15
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Granted: 1982-05-04
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Expires: 2001-06-15
Abstract
Abstract Methods of treating coal to remove sulfur and ash are provided which involve the steps of preconditioning coal particles in the presence of an aqueous solution of an oxidizing agent, washing said pretreated coal with water, contacting said coal with an aqueous solution of an oxidizing agent until an exothermic reaction between the coal and oxidizing agent peaks and the pH drops to the range of 2 to 3, removing the coal from the oxidizing agent, contacting the coal with a passivating agent until the temperature of the coal drops and the pH rises into the range 3 to 5, neutralizing the coal up to a pH of about 9, washing said coal with water and drying said coal.
Inventors
- 👤 Robert Bender
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 22:59
CPC Classifications
C; C10; C10L; C10L9/00; C10L9/02
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
137 words
A process for treating coal to reduce the sulfur and ash content and produce a usable by-product from said sulfur and ash comprising the steps of: a. preconditioning coal particles in the pressence of an aqueous solution of an oxidizing agent, b. washing said pretreated coal with water, c. contacting said coal with an aqueous solution of an oxidizing agent until an exothermic reaction between the coal and oxidizing agent peaks and the pH drops to the range of 2 to 3, d. removing the coal from the oxidizing agent, e. contacting the coal with a passivating agent until the temperature of the coal drops and the pH rises into the range 3 to 5, f. neutralizing the coal up to a pH of about 9, g. washing said coal with water, and h. drying said coal.
Claim 2
Dependent Claim
137 words
A process for treating coal to reduce the sulfur and ash content and produce a usable by-product from said sulfur and ash comprising the steps of: a. preconditioning coal particles in the pressence of an aqueous solution of an oxidizing agent, b. washing said pretreated coal with water, c. contacting said coal with an aqueous solution of an oxidizing agent until an exothermic reaction between the coal and oxidizing agent peaks and the pH drops to the range of 2 to 3, d. removing the coal from the oxidizing agent, e. contacting the coal with a passivating agent until the temperature of the coal drops and the pH rises into the range 3 to 5, f. neutralizing the coal up to a pH of about 9, g. washing said coal with water, and h. drying said coal.
Claim 3
Dependent Claim
15 words
A process as claimed claim 1 wherein the neutralized reaction products of sulfur are recovered.
Claim 4
Dependent Claim
24 words
A process as claimed in claim 1 or 2 wherein the coal particles are preconditioned by soaking for about 5 minutes in oxidizing agent.
Claim 5
Dependent Claim
42 words
A process as claimed in claim 3 wherein the oxidizing agent is one or more members selected from the group consisting of H 2 O 2 , HNO 3 , NClO 4 , HF, O 2 , air and CO 2 .
Claim 6
Dependent Claim
20 words
A process as claimed in claim 3 wherein a surface active agent is added to the solution of oxidizing agent.
Claim 7
Dependent Claim
41 words
A process as claimed in claim 3 wherein the coal passivating agent is one or more members selected from the group consisting of carbon dioxide, carbon monoxide, carbonic acids, dicarboxylic acids, ketones, aldehydes, alcohols, diols, polyols, amino polycarboxylic acids and amines.
Claim 8
Dependent Claim
38 words
A process as claimed in claim 3 wherein the neutralizing agent is an aqueous solution of one or more members selected from the group consisting of alkali metal hydroxides, alkaline earth metal hydroxides, ammonium hydroxide, and ammonium salts.
Claim 9
Dependent Claim
24 words
A process as claimed in claim 3 wherein the oxidizing agent is present in a concentration of about 5% -40% by weight of solution.
Claim 10
Dependent Claim
25 words
A process as claimed in claim 3 wherein the passivating agent is present in a concentration of about 1% to 50% by weight of solution.
Claim 11
Dependent Claim
28 words
A process as claimed in claim 3 wherein the neutralizing agent is present in a concentration of about 1% to 10% by weight of the total aqueous solution.
Claim 12
Dependent Claim
38 words
A process as claimed in claim 5 wherein the surface active agent is a member from the group consisting of cationic, anionic or non-ionic surfactants in a concentrations of about 0.01% to 1.0% by weight of oxidizing reagent.
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) | 1985-05-03 | 1985-11-02 | 1986-05-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-05-03 | 1989-11-02 | 1990-05-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-05-03 | 1993-11-02 | 1994-05-04 | $7700.00 | Window Closed / Lapsed |