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US5401322A Expired / Lapsed US ⏱️ 0.0 years remaining

Apparatus and method for cleaning articles utilizing supercritical and near supercritical fluids

Assignee: Southwest Research Institute
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Filing: 1992-06-30
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Granted: 1995-03-28
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Expires: 2012-06-30
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Abstract

Abstract Disclosed is an apparatus and method of removing contaminants from an article utilizing a supercritical or near supercritical fluid. The article to be cleaned is first contacted with a fluid in which the contaminant is soluble at a first supercritical or near temperature. The contaminate solubilized fluid is then cooled or heated to a second supercritical or near supercritical temperature to lower the solubility of the contaminant in the supercritical fluid and thereby precipitate the contaminant. The contaminant is then recovered.

Inventors

  • 👤 Mary C. Marshall

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-09 02:14
CPC Classifications
B; B08; B08B; B08B7/00; B08B7/0064; B08B7/0021; Y; Y10; Y10S; Y10S134/00; Y10S134/902

Claims Analysis

Total Claims: 6
Claim 1
Independent Claim 128 words
A process for removing a contaminant from an article, the process comprising: (a) contacting the article with a supercritical fluid comprising carbon dioxide in which the contaminant is soluble to solubilize the contaminant, said supercritical fluid being a fluid at a first pressure above its critical pressure and a first temperature above its critical temperature, solubility of the contaminant in said supercritical fluid at said first pressure and said first temperature exceeding solubility of the contaminant in said supercritical fluid at said first pressure and a second temperature above its critical temperature; (b) precipitating from said supercritical fluid at substantially said first pressure above its critical pressure and said second temperature above its critical temperature at least a portion of the solubilized contaminant; and (c) recovering the contaminant.
Claim 2
Dependent Claim 128 words
A process for removing a contaminant from an article, the process comprising: (a) contacting the article with a supercritical fluid comprising carbon dioxide in which the contaminant is soluble to solubilize the contaminant, said supercritical fluid being a fluid at a first pressure above its critical pressure and a first temperature above its critical temperature, solubility of the contaminant in said supercritical fluid at said first pressure and said first temperature exceeding solubility of the contaminant in said supercritical fluid at said first pressure and a second temperature above its critical temperature; (b) precipitating from said supercritical fluid at substantially said first pressure above its critical pressure and said second temperature above its critical temperature at least a portion of the solubilized contaminant; and (c) recovering the contaminant.
Claim 3
Dependent Claim 132 words
A process for removing a contaminant from an article, the process comprising: (a) contacting the article with a supercritical fluid comprising ethylene, with naphthalene as a cosolvent, in which the contaminant is soluble to solubilize the contaminant, said supercritical fluid being a fluid at a first pressure above its critical pressure and a first temperature above its critical temperature, solubility of the contaminant in said supercritical fluid at said first pressure and said first temperature exceeding solubility of the contaminant in said supercritical fluid at said first pressure and a second temperature above its critical temperature; (b) precipitating from said supercritical fluid at substantially said first pressure above its critical pressure and said second temperature above its critical temperature at least a portion of the solubilized contaminant; and (c) recovering the contaminant.
Claim 4
Dependent Claim 132 words
A process for removing a contaminant from an article, the process comprising: (a) contacting the article with a supercritical fluid comprising ethylene, with naphthalene as a cosolvent, in which the contaminant is soluble to solubilize the contaminant, said supercritical fluid being a fluid at a first pressure above its critical pressure and a first temperature above its critical temperature, solubility of the contaminant in said supercritical fluid at said first pressure and said first temperature exceeding solubility of the contaminant in said supercritical fluid at said first pressure and a second temperature above its critical temperature; (b) precipitating from said supercritical fluid at substantially said first pressure above its critical pressure and said second temperature above its critical temperature at least a portion of the solubilized contaminant; and (c) recovering the contaminant.
Claim 5
Dependent Claim 138 words
A process for removing a contaminant from an article, the process comprising: (a) contacting the article with a supercritical fluid comprising an unsaturated C 2 -C 5 alkene, with naphthalene as a cosolvent, in which the contaminant is soluble to solubilize the contaminant, said supercritical fluid being a fluid at a first pressure above its critical pressure and a first temperature above its critical temperature, solubility of the contaminant in said supercritical fluid at said first pressure and said first temperature exceeding solubility of the contaminant in said supercritical fluid at said first pressure and a second temperature above its critical temperature; (b) precipitating from said supercritical fluid at substantially said first pressure above its critical pressure and said second temperature above its critical temperature at least a portion of the solubilized contaminant; and (c) recovering the contaminant.
Claim 6
Dependent Claim 138 words
A process for removing a contaminant from an article, the process comprising: (a) contacting the article with a supercritical fluid comprising an unsaturated C 2 -C 5 alkene, with naphthalene as a cosolvent, in which the contaminant is soluble to solubilize the contaminant, said supercritical fluid being a fluid at a first pressure above its critical pressure and a first temperature above its critical temperature, solubility of the contaminant in said supercritical fluid at said first pressure and said first temperature exceeding solubility of the contaminant in said supercritical fluid at said first pressure and a second temperature above its critical temperature; (b) precipitating from said supercritical fluid at substantially said first pressure above its critical pressure and said second temperature above its critical temperature at least a portion of the solubilized contaminant; and (c) recovering the contaminant.

References Cited (Backward Citations)

US1875937A Cited
US2123439A Cited
US3166445A Cited
US3663293A Cited
US4322251A Cited
US4973387A Cited
US4628616A Cited
US4944837A Cited
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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) 1998-03-27 1998-09-26 1999-03-28 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2002-03-27 2002-09-26 2003-03-28 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2006-03-27 2006-09-26 2007-03-28 $7700.00 Window Closed / Lapsed

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