← Back to Patent Explorer
US4423018A Expired / Lapsed US ⏱️ 0.0 years remaining

Buffered flue gas scrubbing system using adipic acid by-product stream

Assignee: Monsanto Co
•
Filing: 1982-06-23
•
Granted: 1983-12-27
•
Expires: 2002-06-23
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract A by-product stream from the production of adipic acid from cyclohexane, containing glutaric acid, succinic acid and adipic acid, is employed as a buffer in lime or limestone flue gas scrubbing for the removal of sulfur dioxide from combustion gases.

Inventors

  • 👤 J. Harvey Lester, Jr.
  • 👤 Donald E. Danly

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-28 22:47
CPC Classifications
B; B01; B01D; B01D53/00; B01D53/34; B01D53/46; B01D53/48; B01D53/50; B01D53/507; B01D53/501

Claims Analysis

Total Claims: 8
Claim 1
Independent Claim 131 words
In a method for the removal of sulfur dioxide from waste combustion gases which comprises bringing the gases into interfacial contact with an aqueous solution or slurry of limestone or lime buffered by a compound or compounds which significantly increase the dissolution of limestone or lime, the improvement comprising employing as the buffer a byproduct stream which is the byproduct of the process comprising: (1) oxidizing cyclohexane to cyclohexanol and cyclohexanone; (2) oxidizing the cyclohexanol and cyclohexanone with a strong oxidizing acid into a product stream comprising adipic acid with minor amounts of glutaric and succinic acids; (3) crystallizing adipic acid from the product stream in one or more stages leaving said byproduct stream comprising glutaric acid, succinic acid, residual amounts of adipic acid and water, and the strong oxidizing acid.
Claim 2
Dependent Claim 131 words
In a method for the removal of sulfur dioxide from waste combustion gases which comprises bringing the gases into interfacial contact with an aqueous solution or slurry of limestone or lime buffered by a compound or compounds which significantly increase the dissolution of limestone or lime, the improvement comprising employing as the buffer a byproduct stream which is the byproduct of the process comprising: (1) oxidizing cyclohexane to cyclohexanol and cyclohexanone; (2) oxidizing the cyclohexanol and cyclohexanone with a strong oxidizing acid into a product stream comprising adipic acid with minor amounts of glutaric and succinic acids; (3) crystallizing adipic acid from the product stream in one or more stages leaving said byproduct stream comprising glutaric acid, succinic acid, residual amounts of adipic acid and water, and the strong oxidizing acid.
Claim 3
Dependent Claim 29 words
The method of claim 1 wherein the oxidation of cyclohexane is in the presence of boric acid and the byproduct stream further includes residual amounts of the boric acid.
Claim 4
Dependent Claim 21 words
The method of claim 1 wherein the strong oxidizing acid is nitric acid and the byproduct stream further includes nitric acid.
Claim 5
Dependent Claim 17 words
The method of claim 3 wherein the byproduct stream further includes residual amounts of copper and vanadium.
Claim 6
Dependent Claim 37 words
The method of claim 1 wherein the oxidation is in the presence of boric acid and the strong oxidizing acid is nitric acid and the byproduct stream contains residual amounts of both boric acid and nitric acid.
Claim 7
Dependent Claim 16 words
The method of claim 1 wherein the organic acid concentration in the stream is 2-70 meq/liter.
Claim 8
Dependent Claim 17 words
The method of claim 5 wherein the concentration of organic acid in the stream is 45-55 meq/liter.

References Cited (Backward Citations)

US2729543A Cited
US4375552A Cited
US3632306A Cited
US3798309A Cited
US4222993A Cited
US4133650A Cited
US4203954A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1986-12-26 1987-06-27 1987-12-27 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1990-12-26 1991-06-27 1991-12-27 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1994-12-26 1995-06-27 1995-12-27 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag