Claims
- 1. A process for purifying a stream comprising contacting a stream comprising (a) a halogenated compound of the formula:CnHmClpX′k wherein each X′ is an independently selected halogen other than chlorine; m, n, and p are integers with the provisos that: 1≧n≧10; n>p; k≧1; m≧1; and 2n+2=m+p+k and (b) a chlorinated methane impurity other than said halogenated compound with a polymer adsorbent to reduce the level of said chlorinated methane impurity relative to the level of said halogenated compound in said stream, said polymer adsorbent having a pore size distribution characterized by a higher cumulative porosity as a function of the log of pore diameter than that of activated carbon.
- 2. The process of claim 1, wherein said polymer adsorbent comprises a matrix of at least one cross-linked styrenic polymer.
- 3. The process of claim 2, wherein said chlorinated methane impurity has the formula:CHwClyXz wherein each X is an independently selected halogen; w, y, and z are integers with the provisos that: y≧1 and w+y+z=4.
- 4. The process of claim 3, wherein X is fluorine.
- 5. The process of claim 4, wherein said chlorinated methane impurity is CH2ClF.
- 6. The process of claim 5, wherein said stream has a space velocity of no greater than about 100 hr−1 over a period of no greater than about 4 hours to result in a purified stream containing less than about 10 ppm of HCFC-31.
- 7. The process of claim 1, wherein X′ is fluorine, p=0, and n≦3.
- 8. The process of claim 7, wherein the halogenated compound is HFC-32.
- 9. The process of claim 1, wherein said pore size distribution is characterized by the cumulative porosity as a function of the log of pore size being no less than about 0.43 cc/g.
- 10. The process of claim 1, wherein said pore size distribution is characterized by a cumulative porosity that increases exponentially as a function of the log of pore diameter.
- 11. A process for purifying a stream comprising:contacting a stream comprising (a) a halogenated compound of the formula: CnHmClpX′k wherein each X′ is an independently selected halogen other than chlorine; m, n, and p are integers with the provisos that: 1≧n≧10; n>p; k≧1; m≧1; and 2n+2=m+p+k and (b) a chlorinated methane impurity other than said halogenated compound with a polymeric adsorbent to reduce the level of said chlorinated methane impurity relative to the level of said halogenated compound in said stream, said polymeric adsorbent comprising a matrix of at least one cross-linked styrenic polymer having a total porosity of at least about 0.8 cc/g, an average pore diameter of about 30 to about 60 Å, and a BET surface area of at least about 900 m2/g.
- 12. The process of claim 11, wherein said total porosity is about 1.1 to about 1.2 cc/g, average pore diameter is about 40 to about 50 Å, and BET surface area is at least about 1100 m2/g.
- 13. The process of claim 12, wherein said total porosity is about 1.16 cc/g, average pore diameter is about 46 Å, and BET surface area is about 1100 m2/g.
- 14. The process of claim 13, wherein said adsorbent is in the form of particles having a diameter of about 10 to about 70 mesh.
- 15. The process of claim 11, wherein said chlorinated methane impurity has the formula:CHwClyXz wherein each X is an independently selected halogen; w, y, and z are integers with the provisos that: y≧1 and w+y+z=4.
- 16. The process of claim 15, wherein said chlorinated methane impurity is CH2ClF.
- 17. The process of claim 11, wherein X′ is fluorine, p=0, and n≦3.
- 18. The process of claim 17, wherein the halogenated compound is HFC-32.
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a continuation of U.S. application Ser. No. 09/678,861 (now abandoned) which was filed with the U.S. Patent and Trademark Office on Oct. 3, 2000, and which, in turn, claims the benefit of U.S. Provisional Application No. 60/158,535 which was filed with the United States Patent and Trademark Office on Oct. 8, 1999.
US Referenced Citations (4)
Non-Patent Literature Citations (6)
Entry |
“Polymeric Adsorbent XUS 43493” Dow Technical Bulletin 3.03.* |
Dow Product Information Document—Polymeric Adsorbent XUS 43493 Technical Bulletin 3.03. |
Dow Product Information Document—Dowex Optipore V493 Polymeric adsorbent for removal of organics from air streams, Dowex ion exchange resins and adsorbents. |
Dow Product Information Document—Dowex Optipore Adsorbents Syrene Emissions Control. |
Dow Product Information Document—Dowex Optipore L493 and V493 Dowex *Optipore* L493 and Dowex Optipore V493 Polymeric Adsorbent. |
Dow Product Information Document—Dow Liquid Separations Dowex Optipore Adsorbents Fluidized Bed Properties of Dow Polymeric Adsorbents. |
Provisional Applications (1)
|
Number |
Date |
Country |
|
60/158535 |
Oct 1999 |
US |
Continuations (1)
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Number |
Date |
Country |
Parent |
09/678861 |
Oct 2000 |
US |
Child |
10/377922 |
|
US |