← Back to Patent Explorer
US4336034A Expired / Lapsed US ⏱️ 0.0 years remaining

Process for the catalytic gasification of coal

Assignee: ExxonMobil Technology and Engineering Co
•
Filing: 1980-03-10
•
Granted: 1982-06-22
•
Expires: 2000-03-10
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract Carbonaceous solids are contacted in the presence of water with potassium sulfate and a calcium compound selected from the group consisting of calcium oxide, calcium hydroxide, and calcium carbonate thereby producing treated carbonaceous solids which are then gasified. The calcium compound apparently activates the relatively noncatalytic potassium sulfate thereby producing a substantial catalytic effect on the gasification reactions.

Inventors

  • 👤 Robert J. Lang
  • 👤 Joanne K. Pabst

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-30 14:34
CPC Classifications
C; C10; C10J; C10J3/00; C10J3/46; C10J3/48; C10J3/482; C10J3/54; C10J2300/00; C10J2300/09; C10J2300/0913; C10J2300/093; C10J2300/0953; C10J2300/0973; C10J2300/0983; C10J2300/0986; C10J2300/18; C10J2300/1807; C10J2300/1853; Y; Y02; Y02P; Y02P20/00; Y02P20/50; Y02P20/52

Claims Analysis

Total Claims: 10
Claim 1
Independent Claim 184 words
A process for the catalytic steam gasification of coal which comprises: (a) contacting said coal in the presence of water with potassium sulfate and a calcium compound selected from the group consisting of calcium oxide and calcium hydroxide in a contacting zone to produce a treated coal, wherein said calcium compound is present in a sufficient quantity to activate said potassium sulfate; (b) passing said treated coal from said contacting zone into a gasification zone; and (c) gasifying said treated coal with steam at a temperature between about 1200° F. and about 1400° F. in said gasification zone, wherein said potassium sulfate and said calcium compound are introduced into said contacting zone in sufficient amounts to obtain gasification rates substantially greater than the weighted average of the separate rates that would be obtained if said potassium sulfate or calcium compound were introduced alone into said contacting zone in sufficient amounts to give a cation-to-carbon atomic ratio equal to the sum of the potassium-to-carbon and calcium-to-carbon atomic ratios given by the amount of said potassium and said calcium compound actually introduced into said contacting zone.
Claim 2
Dependent Claim 184 words
A process for the catalytic steam gasification of coal which comprises: (a) contacting said coal in the presence of water with potassium sulfate and a calcium compound selected from the group consisting of calcium oxide and calcium hydroxide in a contacting zone to produce a treated coal, wherein said calcium compound is present in a sufficient quantity to activate said potassium sulfate; (b) passing said treated coal from said contacting zone into a gasification zone; and (c) gasifying said treated coal with steam at a temperature between about 1200° F. and about 1400° F. in said gasification zone, wherein said potassium sulfate and said calcium compound are introduced into said contacting zone in sufficient amounts to obtain gasification rates substantially greater than the weighted average of the separate rates that would be obtained if said potassium sulfate or calcium compound were introduced alone into said contacting zone in sufficient amounts to give a cation-to-carbon atomic ratio equal to the sum of the potassium-to-carbon and calcium-to-carbon atomic ratios given by the amount of said potassium and said calcium compound actually introduced into said contacting zone.
Claim 3
Dependent Claim 14 words
A process as defined by claim 1 wherein said calcium compound comprises calcium hydroxide.
Claim 4
Dependent Claim 30 words
A process as defined by claim 1 wherein said calcium compound is present in a sufficient quantity to yield a potassium-to-calcium atomic ratio of between about 1.33 and about 4.0.
Claim 5
Dependent Claim 38 words
A process as defined by claim 1 wherein said coal is contacted with said potassium sulfate and said calcium compound in the presence of water for a period of time between about 30 minutes and about 120 minutes.
Claim 6
Dependent Claim 15 words
A process as defined by claim 1 wherein said coal comprises a low rank coal.
Claim 7
Dependent Claim 14 words
A process as defined by claim 1 wherein said calcium compound comprises calcium oxide.
Claim 8
Dependent Claim 26 words
A process as defined by claim 3 wherein said calcium compound is present in a sufficient quantity to yield a potassium-to-calcium atomic ratio of about 2.0.
Claim 9
Dependent Claim 14 words
A process as defined by claim 1 wherein said carbonaceous solids comprise subbituminous coal.
Claim 10
Dependent Claim 13 words
A process as defined by claim 1 wherein said carbonaceous solids comprise lignite.

References Cited (Backward Citations)

US4094650A Cited
US4092125A Cited
US4069304A Cited
US4204843A Cited
GB2010315B Cited
US4157246A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1985-06-21 1985-12-21 1986-06-22 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1989-06-21 1989-12-21 1990-06-22 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1993-06-21 1993-12-21 1994-06-22 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag