US4374654A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Absorptive separation of HCl and H2 S from catalytic reformer offgas
Assignee: Chevron USA Inc
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Filing: 1981-08-03
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Granted: 1983-02-22
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Expires: 2001-08-03
Abstract
Abstract A two stage low temperature adsorptive separation process for removing HCl and H 2 S from a catalytic reforming offgas to make the offgas useful as a feed to a steam reforming process. In the first stage the offgas is passed through a molecular sieve bed that adsorbs HCl selectively. In the second bed the HCl depleted offgas is passed through a zinc oxide bed to remove the H 2 S. The H 2 S and HCl content of the offgas are reduced to levels that do not significantly poison the catalysts used in the steam reforming process.
Inventors
- 👤 Charles S. McCoy
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 12:58
CPC Classifications
C; C01; C01B; C01B3/00; C01B3/02; C01B3/32; C01B3/34; B; B01; B01D; B01D53/00; B01D53/02; B01D53/04; B01D2253/00; B01D2253/10; B01D2253/104; B01D2253/106; B01D2253/108; B01D2253/112; B01D2257/00; B01D2257/20; B01D2257/204; B01D2257/2045; B01D2257/30; B01D2257/304; B01D2259/00; B01D2259/40; B01D2259/402; B01D2259/414; B01D2259/4141; B01D2259/4145; B01D2259/4146
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
140 words
A substantially continuous adsorptive separation process for removing HCl and H 2 S from a catalytic reforming offgas that contains less than about 10 ppm each of HCl and H 2 S to make the offgas useful as a feedgas for a steam reforming process comprising: (a) passing the offgas at a temperature in the range of about 40° C. to 70° C. through a molecular sieve or activated alumina bed that adsorbs HCl selectively from the offgas, and (b) thereafter passing the HCl-depleted offgas at said temperature through a zinc oxide bed that adsorbs H 2 S from the offgas, whereby HCl and H 2 S are removed from the offgas to an extent that the HCl and H 2 S contents of the offgas leaving the beds are below that which would significantly poison a steam reforming catalyst.
Claim 2
Dependent Claim
140 words
A substantially continuous adsorptive separation process for removing HCl and H 2 S from a catalytic reforming offgas that contains less than about 10 ppm each of HCl and H 2 S to make the offgas useful as a feedgas for a steam reforming process comprising: (a) passing the offgas at a temperature in the range of about 40° C. to 70° C. through a molecular sieve or activated alumina bed that adsorbs HCl selectively from the offgas, and (b) thereafter passing the HCl-depleted offgas at said temperature through a zinc oxide bed that adsorbs H 2 S from the offgas, whereby HCl and H 2 S are removed from the offgas to an extent that the HCl and H 2 S contents of the offgas leaving the beds are below that which would significantly poison a steam reforming catalyst.
Claim 3
Dependent Claim
24 words
The process of claim 1 wherein the offgas contains less than about 5 ppm HCl and less than about 5 ppm H 2 S.
Claim 4
Dependent Claim
25 words
The process of claim 1 wherein the HCl and H 2 S contents of the offgas leaving the beds are each below about 0.1 ppm.
Claim 5
Dependent Claim
17 words
The process of claims 1, 2 or 3 wherein the molecular sieve is a type 4A zeolite.
Claim 6
Dependent Claim
82 words
The process of claim 1 wherein the flow rate of offgas through the molecular sieve bed based on the gas volume per hour at standard temperature and pressure per volume of sieve is in the range of about 2000 to about 20000 v/v/hr and the gas flow rate of offgas through the zinc oxide bed based on the gas volume per hour at standard temperature and pressure per zinc oxide volume is in the range of about 1000 to about 10000 v/v/hr.
Claim 7
Dependent Claim
137 words
A substantially continuous adsorptive separation process for removing HCl and H 2 S from a catalytic reforming offgas that contains less than about 10 ppm each of HCl and H 2 S to make the offgas useful as a feedgas for a steam reforming process comprising: (a) passing the offgas at a temperature in the range of about 40° C. to 70° C. through an activated alumina bed that adsorbs HCl selectively from the offgas, and (b) thereafter passing the HCl-depleted offgas at said temperature through a zinc oxide bed that adsorbs H 2 S from the offgas, whereby HCl and H 2 S are removed from the offgas to an extent that the HCl and H 2 S contents of the offgas leaving the beds are below that which would significantly poison a steam reforming catalyst.
Claim 8
Dependent Claim
137 words
A substantially continuous adsorptive separation process for removing HCl and H 2 S from a catalytic reforming offgas that contains less than about 10 ppm each of HCl and H 2 S to make the offgas useful as a feedgas for a steam reforming process comprising: (a) passing the offgas at a temperature in the range of about 40° C. to 70° C. through an activated alumina bed that adsorbs HCl selectively from the offgas, and (b) thereafter passing the HCl-depleted offgas at said temperature through a zinc oxide bed that adsorbs H 2 S from the offgas, whereby HCl and H 2 S are removed from the offgas to an extent that the HCl and H 2 S contents of the offgas leaving the beds are below that which would significantly poison a steam reforming catalyst.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-02-21 | 1986-08-23 | 1987-02-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-02-21 | 1990-08-23 | 1991-02-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-02-21 | 1994-08-23 | 1995-02-22 | $7700.00 | Window Closed / Lapsed |