US4351716A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Liquefaction process
Assignee: ExxonMobil Technology and Engineering Co
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Filing: 1979-03-15
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Granted: 1982-09-28
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Expires: 1999-03-15
Abstract
Abstract Scale formation during the liquefaction of lower ranking coals and similar carbonaceous materials is significantly reduced and/or prevented by pretreatment with a combination of pretreating agents comprising SO 2 and an oxidizing agent. The pretreatment is believed to convert at least a portion of the scale-forming components and particularly calcium, to the corresponding sulfate prior to liquefaction. The pretreatment may be accomplished with the combination of pretreating agents either simultaneously by using a mixture comprising SO 2 and an oxidizing agent or sequentially by first treating with SO 2 and then with an oxidizing agent.
Inventors
- 👤 Martin L. Gorbaty
- 👤 John B. Stone
- 👤 Syamal K. Poddar
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 01:30
CPC Classifications
C; C10; C10G; C10G1/00; Y; Y10; Y10S; Y10S208/00; Y10S208/951
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
69 words
A process for the liquefaction of a lower ranking coal comprising the steps of: (a) contacting said coal with a gaseous mixture comprising sulfur dioxide and an oxidizing agent so as to reduce the amount of alkaline earth metal humates therein; (b) liquefying the thus treated coal at liquefaction conditions to produce a petroleum-like product; and (c) recovering the liquid product from the unliquefied portion of the pretreated coal.
Claim 2
Dependent Claim
69 words
A process for the liquefaction of a lower ranking coal comprising the steps of: (a) contacting said coal with a gaseous mixture comprising sulfur dioxide and an oxidizing agent so as to reduce the amount of alkaline earth metal humates therein; (b) liquefying the thus treated coal at liquefaction conditions to produce a petroleum-like product; and (c) recovering the liquid product from the unliquefied portion of the pretreated coal.
Claim 3
Dependent Claim
22 words
The process in claim 1 wherein the coal or is ground so that all particles are less than 1-quarter inch in diameter.
Claim 4
Dependent Claim
43 words
The process in claim 1 wherein the coal is contacted with sulfur dioxide at a total pressure within the range from about 15 to about 50 psia and a sulfur dioxide partial pressure within the range from about 0.5 to about 40 psia.
Claim 5
Dependent Claim
34 words
The process of claim 3 wherein the contacting is accomplished with a gaseous mixture comprising SO 2 and from about 0.25 to about 1.5 mols of O 2 per mol of SO 2 .
Claim 6
Dependent Claim
21 words
The process of claim 4 wherein the nominal contacting time is within the range from about 10 to about 60 minutes.
Claim 7
Dependent Claim
17 words
The method of claim 1 wherein the liquefaction is accomplished in the presence of added molecular hydrogen.
Claim 8
Dependent Claim
34 words
The method of claim 6 wherein the liquefaction is accomplished at a temperature of about 800° to about 880° F. and at a pressure within the range from about 1500 to about 2000 psig.
Claim 9
Dependent Claim
66 words
A process for the liquefaction of a lower ranking coal comprising the steps of: (a) contacting said coal with gaseous sulphur dioxide and an oxidizing agent so as to reduce the amount of alkaline earth metal humates therein; (b) liquefying the thus treated coal at liquefaction conditions to produce a petroleum-like product; and (c) separating the liquid product from the unliquefied portion of the pretreated coal.
Claim 10
Dependent Claim
66 words
A process for the liquefaction of a lower ranking coal comprising the steps of: (a) contacting said coal with gaseous sulphur dioxide and an oxidizing agent so as to reduce the amount of alkaline earth metal humates therein; (b) liquefying the thus treated coal at liquefaction conditions to produce a petroleum-like product; and (c) separating the liquid product from the unliquefied portion of the pretreated coal.
Claim 11
Dependent Claim
16 words
The process of claim 8 wherein the coal contains between 25 and 40 wt % water.
Claim 12
Dependent Claim
27 words
The process of claim 9 wherein the contacting is accomplished sequentially such that the coal is first contacted with gaseous sulphur dioxide and then an oxidizing agent.
Claim 13
Dependent Claim
14 words
The process of claim 10 wherein the oxidizing agent is a gaseous oxidizing agent.
Claim 14
Dependent Claim
12 words
The process of claim 10 wherein the oxidizing agent is a liquid.
Claim 15
Dependent Claim
21 words
The process of claim 8 wherein the partial pressure of sulphur dioxide during the pretreatment is at least about 0.5 psi.
Claim 16
Dependent Claim
32 words
The process of claim 10 wherein the contacting with SO 2 is continued for at least five minutes and the contacting with the oxidizing agent is continued for at least five minutes.
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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) | 1985-09-27 | 1986-03-29 | 1986-09-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-09-27 | 1990-03-29 | 1990-09-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-09-27 | 1994-03-29 | 1994-09-28 | $7700.00 | Window Closed / Lapsed |