Claims
- 1. A method for the preparation of ultra-high-purity ammonia, said method comprising:
- (a) drawing ammonia gas from a vapor space above liquid ammonia in an ammonia-containing reservoir;
- (b) passing said ammonia gas through a unit whereby said ammonia gas is contacted with an aqueous solution of ammonia in deionized water, thereby purifying said ammonia gas; and
- (c) recovering said purified ammonia gas emerging from said unit.
- 2. A method in accordance with claim 1, further comprising dissolving said ammonia gas emerging from said scrubber in purified water.
- 3. A method in accordance with claim 1, further comprising passing said ammonia gas through a distillation column for further purification.
- 4. A method in accordance with claim 1, further comprising the additional step of:
- (b') passing said purified ammonia gas from said unit through a distillation column for further purification, and dissolving said ammonia gas emerging from said distillation column in purified water.
- 5. A method in accordance with claim 4, in which steps (b) and (b') are conducted at a temperature ranging from about 15.degree. to about 35.degree. C.
- 6. A method in accordance with claim 4, in which steps (b) and (b') are conducted at a temperature ranging from about 15.degree. to about 35.degree. C. and at a pressure of from about atmospheric pressure to about 30 psi above atmospheric pressure.
- 7. A method in accordance with claim 1, in which step (b) is conducted at a temperature ranging from about 10.degree. to about 50.degree. C.
- 8. A method in accordance with claim 7, in which step (b) is conducted at a temperature ranging from about 15.degree. to about 35.degree. C.
- 9. A method in accordance with claim 1, in which step (b) is conducted at a temperature ranging from about 15.degree. to about 35.degree. C. and at a pressure of from about atmospheric pressure to about 30 psi above atmospheric pressure.
Parent Case Info
This application is a continuation of application Ser. No. 08/674,110, filed Jul. 1, 1996, now U.S. Pat. No. 5,846,386, which is a continuation-in-part of application Ser. No. 08/610,261, filed Mar. 4, 1996 now U.S. Pat. No. 5,755,934, which is a continuation of application Ser. No. 08/179,001, filed Jan. 7, 1994, now U.S. Pat. No. 5,496,778; said Ser. No. 08/674,110 which is a application of PCT applications No. PCT/US96/09570, filed Jun. 5, 1996 and of PCT/US95/07649, filed Jun. 5, 1995. The present application also claims benefit of priority through application Ser. No. 08,674,110 of provisional application No. 60/023,358, filed Jul. 7, 1995.
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Related Publications (2)
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Date |
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PCTUS9507649 |
Jun 1995 |
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610261 |
Mar 1996 |
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Continuations (2)
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Number |
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Parent |
674110 |
Jul 1996 |
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Parent |
179001 |
Jan 1994 |
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Continuation in Parts (1)
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Date |
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PCTUS9609570 |
Jun 1996 |
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