US3998932A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for the catalytic synthesis of ammonia
Assignee: Montedison Fibre SpA
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Filing: 1975-02-28
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Granted: 1974-12-21
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Expires: 1995-02-28
Abstract
Abstract A catalytic process and apparatus for synthesizing ammonia wherein from 30 to 80% of the effluent gases containing at least 12 molar percent ammonia are recycled to the inlet of the catalyst bed.
Inventors
- 👤 Amilcare Collina
- 👤 Emanuele Malfatti
- 👤 Antonio Cappelli
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 04:20
CPC Classifications
C; C01; C01C; C01C1/00; C01C1/02; C01C1/04; C01C1/0405; C01C1/0417; C01C1/0423; B; B01; B01J; B01J8/00; B01J8/02; B01J8/0207; B01J8/0214; Y; Y02; Y02P; Y02P20/00; Y02P20/50; Y02P20/52
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
150 words
A process for manufacturing ammonia with only one catalyst bed which comprises flowing over said catalyst bed containing iron a gaseous feed stream containing nitrogen and hydrogen at a space velocity, temperature and pressure which produce an effluent gas from the said catalyst bed which contains at least 12 molar percentage of ammonia, mixing the said feed stream with from 30 to 80% of said effluent gas recycled directly from the said catalyst bed and passing the resulting mixture at a space velocity of from 20,000 to 70,000 h - 1 , a temperature of from 300° to 600° C, and under a pressure of from 150 to 450 kg/cm 2 over the said catalyst bed, the difference between the molar percentage of ammonia in the effluent gas and in the said mixture being from 3 to 6, and recovering ammonia from the nonrecycled portion of the said effluent gas.
Claim 2
Dependent Claim
150 words
A process for manufacturing ammonia with only one catalyst bed which comprises flowing over said catalyst bed containing iron a gaseous feed stream containing nitrogen and hydrogen at a space velocity, temperature and pressure which produce an effluent gas from the said catalyst bed which contains at least 12 molar percentage of ammonia, mixing the said feed stream with from 30 to 80% of said effluent gas recycled directly from the said catalyst bed and passing the resulting mixture at a space velocity of from 20,000 to 70,000 h - 1 , a temperature of from 300° to 600° C, and under a pressure of from 150 to 450 kg/cm 2 over the said catalyst bed, the difference between the molar percentage of ammonia in the effluent gas and in the said mixture being from 3 to 6, and recovering ammonia from the nonrecycled portion of the said effluent gas.
Claim 3
Dependent Claim
39 words
The process of claim 1 wherein the pressure is 200 to 300 kg./cm 2 , from 60 to 75% of the gas leaving the catalyst is recycled and the recycled gas contains at least 18 molar percent of ammonia.
Claim 4
Dependent Claim
27 words
The process of claim 1 wherein said direct recycle is performed by means of an injection process in which said direct recycle is representing the driven gas.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-12-20 | 1978-06-21 | 1978-12-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-12-20 | 1982-06-21 | 1982-12-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-12-20 | 1986-06-21 | 1986-12-21 | $7700.00 | Window Closed / Lapsed |