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US4484954A Expired / Lapsed US ⏱️ 0.0 years remaining

Halogenation treatment

Assignee: Praxair Technology Inc
•
Filing: 1982-08-03
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Granted: 1984-11-27
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Expires: 2002-08-03
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Abstract

Abstract A batch process for the halogenation of solid polymeric or metallic material comprising the following steps: (a) providing a closed system comprising a chamber containing air at about atmospheric pressure and having inlet and outlet means, a heat exchanger, and a circulation pump, all connected in series; (b) introducing the material into the chamber; (c) heating the chamber and the material to a selected temperature in the range of about 100° F. to about 200° F. by recirculating the air through the heat exchanger; (d) evacuating the system; (e) introducing a halogen into the system in an amount (i) of up to about 10 percent in excess of the theoretical amount of halogen required to halogenate the polymeric material to a desired depth and (ii) sufficient to provide a partial pressure in the system in the range of about 0.1 psia to about 3 psia; (f) introducing an inert gas into the system in an amount sufficient to provide a total pressure in the system of about one atmosphere; (g) maintaining the selected temperature by recirculating the halogen/inert gas mixture through the heat exchanger; (h) recirculating the halogen/inert gas mixture a sufficient number of times to reduce the amount of halogen to less than about 5 percent of the amount of halogen initially introduced into the system; (i) evacuating the system; (j) introducing air into the system to provide about atmospheric pressure; and (k) removing the material.

Inventors

  • 👤 Gregorio Tarancon

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-08 11:06
CPC Classifications
C; C08; C08J; C08J7/00; C08J7/12; B; B01; B01J; B01J15/00; C08J7/126

Claims Analysis

Total Claims: 5
Claim 1
Independent Claim 254 words
A batch process for the halogenation of solid polymeric or metallic material comprising the following steps: (a) providing a closed system comprising a chamber containing air at about atmospheric pressure and having inlet and outlet means, a heat exchanger, and a circulation pump, all connected in series; (b) introducing the material into the chamber; (c) heating the chamber and the material to a selected temperature in the range of about 100° F. to about 200° F. by recirculating the air through the heat exchanger; (d) evacuating the system to a pressure of less than about 1 psia; (e) introducing a halogen into the system in an amount (i) of up to about 10 percent in excess of the theoretical amount of halogen required to halogenate the material to a desired depth and (ii) sufficient to provide a partial pressure in the system in the range of about 0.1 psia to about 3 psia; (f) introducing an inert gas into the system in an amount sufficient to provide a total pressure in the system of about one atmosphere; (g) maintaining the selected temperature by recirculating the halogen/inert gas mixture through the heat exchanger; (h) recirculating the halogen/inert gas mixture a sufficient number of times to reduce the amount of halogen to less than about 5 percent of the amount of halogen initially introduced into the system; (i) evacuating the system to a pressure of less than about 1 psia; (j) introducing air into the system to provide about atmospheric pressure; and (k) removing the material.
Claim 2
Dependent Claim 254 words
A batch process for the halogenation of solid polymeric or metallic material comprising the following steps: (a) providing a closed system comprising a chamber containing air at about atmospheric pressure and having inlet and outlet means, a heat exchanger, and a circulation pump, all connected in series; (b) introducing the material into the chamber; (c) heating the chamber and the material to a selected temperature in the range of about 100° F. to about 200° F. by recirculating the air through the heat exchanger; (d) evacuating the system to a pressure of less than about 1 psia; (e) introducing a halogen into the system in an amount (i) of up to about 10 percent in excess of the theoretical amount of halogen required to halogenate the material to a desired depth and (ii) sufficient to provide a partial pressure in the system in the range of about 0.1 psia to about 3 psia; (f) introducing an inert gas into the system in an amount sufficient to provide a total pressure in the system of about one atmosphere; (g) maintaining the selected temperature by recirculating the halogen/inert gas mixture through the heat exchanger; (h) recirculating the halogen/inert gas mixture a sufficient number of times to reduce the amount of halogen to less than about 5 percent of the amount of halogen initially introduced into the system; (i) evacuating the system to a pressure of less than about 1 psia; (j) introducing air into the system to provide about atmospheric pressure; and (k) removing the material.
Claim 3
Dependent Claim 63 words
The process defined in claim 1 wherein the temperature range in step (c) is about 120° F. to about 180° F.; the percent in excess of halogen in step (e) (i) is up to about 5 percent; and the reduction of the amount of halogen in step (h) is to less than about 2 percent of the halogen initially introduced into the system.
Claim 4
Dependent Claim 18 words
The process defined in claim 1 wherein the halogen is fluorine or a mixture of fluorine and bromine.
Claim 5
Dependent Claim 18 words
The process defined in claim 2 wherein the halogen is fluorine or a mixture of fluorine and bromine.

References Cited (Backward Citations)

US3009906A Cited
US3639510A Cited
US3598708A Cited
US3758450A Cited
US3775489A Cited
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US4142032A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1987-11-27 1988-05-28 1988-11-27 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1991-11-27 1992-05-28 1992-11-27 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1995-11-27 1996-05-28 1996-11-27 $7700.00 Window Closed / Lapsed

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