Claims
- 1. In a process for hydrolytically decomposing porous polyurethane solids disposed in a chamber and separating liquid polyol therefrom the improvement comprising:
- (A) evacuating said chamber to a pressure below about 10.sup.-1 atmospheres;
- (B) preheating the walls of said chamber and thereafter admitting saturated steam into said chamber to provide at least about 30 atmospheres of pressure therein;
- (C) maintaining a temperature in said chamber sufficient to continue hydrolytic decomposition and to promote separation of gaseous diamine and liquid polyol in said chamber;
- (D) exhausting gaseous effluent from the upper portion of said chamber;
- (E) cooling said chamber; and
- (F) collecting liquid polyol from the lower portion of said chamber.
- 2. A process in accordance with claim 1, wherein said chamber is evacuated to a pressure below 3.times.10.sup.-2 atmospheres.
- 3. A process in accordance with claims 1 or 2, wherein said temperature in said chamber is maintained at a temperature sufficient to continue hydrolytic decomposition and to promote separation in said chamber of gaseous diamine and liquid polyol by maintaining the temperature of the walls of said chamber at a temperature corresponding to about the steam saturation temperature at the selected operating pressure in said chamber.
- 4. A process in accordance with claim 3, wherein said walls of said chamber are maintained at a temperature of about 200.degree. C. or higher.
- 5. A process in accordance with claim 1, wherein said chamber is evacuated subsequent to hydrolytic decomposition of said porous polyurethane solids to remove diamine and water therefrom.
- 6. A process in accordance with claim 5, wherein subsequent to hydrolytic decomposition said chamber is evacuated to a pressure below 10.sup.-1 atmosphere and said walls of said chamber are maintained at a temperature above about 200.degree. C. for a time necessary to distill amine from residual polyol in said chamber.
- 7. A process in accordance with claim 5, wherein subsequent to hydrolytic decomposition said chamber is evacuated to a pressure below 2.times.10.sup.-2 atmospheres and said walls of said chamber are maintained at a temperature of about 271.degree. C. for about 20 minutes.
- 8. A process in accordance with claim 1, wherein said porous polyurethane solids comprise open pore polyurethane foam.
- 9. A process in accordance with claim 8, wherein said foam is compressed to less than 1/5 its original volume.
- 10. A process in accordance with claim 1, wherein said porous polyurethane solids comprise comminuted closed pore polyurethane foam.
- 11. A process in accordance with claim 1, 8, or 10, wherein said porous polyurethane solids in said chamber are disposed in a perforated container.
- 12. A process in accordance with claim 1 or 5, wherein said walls of said chamber are preheated to a temperature corresponding to about the steam saturation temperature at the pressure at which said chamber is to be maintained during hydrolytic decomposition of said porous polyurethane foam.
- 13. A process in accordance with claim 12, wherein said walls of said chamber are preheated to a temperature above about 200.degree. C.
Parent Case Info
This application is a Continuation-In-Part of Ser. No. 049,511 filed June 18, 1979, which is a Continuation of Ser. No. 826,915 filed Aug. 22, 1977 and both now abandoned.
US Referenced Citations (4)
Foreign Referenced Citations (1)
Number |
Date |
Country |
1455454 |
Oct 1976 |
GBX |
Non-Patent Literature Citations (1)
Entry |
Perry, "Chemical Engineer's Handbook", 4th Ed., pp. 8-63 & 8-64 (1974). |
Continuations (1)
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Number |
Date |
Country |
Parent |
826915 |
Aug 1977 |
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Continuation in Parts (1)
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Number |
Date |
Country |
Parent |
49511 |
Jun 1979 |
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