US5166454A
Expired / Lapsed
US
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Etherification process with hydrogen rejuvenation
Assignee: Mobil Oil AS
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Filing: 1991-05-06
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Granted: 1992-11-24
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Expires: 2011-05-06
Abstract
Abstract A multistage process for etherifying C 4 + aliphatic hydrocarbon feedstock containing isoalkane including the step of contacting the hydrocarbon feedstock with dehydrogenation catalyst at elevated temperature under dehydrogenation reaction conditions to obtain C 4 + isoalkene and hydrogen, and separating dehydrogenation effluent to obtain an olefinic stream rich in isoalkene and a hydrogen stream. The olefinic stream and aliphatic alcohol are contacted in an esterification stage under partial etherification conditions with a regenerable inorganic metal oxide acid solid catalyst to convert a major amount of the isoalkene to C 5 + tertiary-alkyl ether. In the preferred embodiment, effluent recovered from the first stage containing ether product, unreacted alcohol and unreacted olefin including isoalkene is charged to a second stage catalytic distillation column containing solid acid resin etherification catalyst in a plurality of fixed bed catalysis-distillation zones to complete substantially full etherification of isoalkene. At least a portion of recovered hydrogen is employed for contacting the regenerable etherification catalyst to remove feedstock impurity and coke and to restore acid activity. In the manufacture of MTBE, the alcohol consists essentially of methanol and the C4+ feedstock consists predominantly of C 4 hydrocarbons containing isobutane. The first etherification stage catalyst may comprise medium pore zeolite and the second stage catalyst may comprise polymeric sulfonic acid resin.
Inventors
- 👤 Mohsen N. Harandi
- 👤 Hartley Owen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 13:03
CPC Classifications
C; C07; C07C; C07C41/00; C07C41/01; C07C41/05; C07C41/06; B; B01; B01D; B01D3/00; B01D3/009; C07C41/34; C07C41/40; C07C41/42; Y; Y02; Y02P; Y02P20/00; Y02P20/10; Y02P20/129; Y10; Y10S; Y10S203/00; Y10S203/06
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
185 words
A multistage process for etherifying a mixed C 4 + aliphatic hydrocarbon feedstock containing isoalkane, comprising: contacting the hydrocarbon feedstock with dehydrogenation catalyst at elevated temperature under dehydrogenation reaction conditions to obtain C 4 + isoalkene and hydrogen; separating dehydrogenation effluent to obtain an olefinic stream rich in isoalkene and a hydrogen stream; contacting the olefinic stream and aliphatic alcohol in a first etherification stage under partial etherification conditions with a regenerable inorganic metal oxide acid solid catalyst to convert a major amount of the isoalkene to C 5 + tertiary-alkyl ether; recovering a reactant effluent from the first stage containing ether product, unreacted alcohol and unreacted olefin including isoalkene; charging the first etherification stage effluent to a second stage catalytic distillation column containing solid acid resin etherification catalyst in a plurality of fixed bed catalysis-distillation zones to complete substantially full etherification of isoalkene; recovering C 5 + ether as a liquid from the catalytic distillation column; contacting the first stage etherification catalyst with said hydrogen stream to remove feedstock impurity and coke and to restore acid activity: and continuing ether production with regenerated catalyst.
Claim 2
Dependent Claim
185 words
A multistage process for etherifying a mixed C 4 + aliphatic hydrocarbon feedstock containing isoalkane, comprising: contacting the hydrocarbon feedstock with dehydrogenation catalyst at elevated temperature under dehydrogenation reaction conditions to obtain C 4 + isoalkene and hydrogen; separating dehydrogenation effluent to obtain an olefinic stream rich in isoalkene and a hydrogen stream; contacting the olefinic stream and aliphatic alcohol in a first etherification stage under partial etherification conditions with a regenerable inorganic metal oxide acid solid catalyst to convert a major amount of the isoalkene to C 5 + tertiary-alkyl ether; recovering a reactant effluent from the first stage containing ether product, unreacted alcohol and unreacted olefin including isoalkene; charging the first etherification stage effluent to a second stage catalytic distillation column containing solid acid resin etherification catalyst in a plurality of fixed bed catalysis-distillation zones to complete substantially full etherification of isoalkene; recovering C 5 + ether as a liquid from the catalytic distillation column; contacting the first stage etherification catalyst with said hydrogen stream to remove feedstock impurity and coke and to restore acid activity: and continuing ether production with regenerated catalyst.
Claim 3
Dependent Claim
30 words
The process of claim 1 wherein the alcohol consists essentially of methanol, the first stage catalyst comprises medium pore zeolite, and the second stage catalyst comprises polymeric sulfonic acid resin.
Claim 4
Dependent Claim
17 words
The process of claim 1 wherein the C4+ feedstock comprises predominantly of C 4 hydrocarbons containing isobutane.
Claim 5
Dependent Claim
31 words
The process of claim 1 wherein the first etherification stage comprises a plurality of fixed bed catalyst zones operatively connected for swing from production mode to regeneration mode in alternating sequence.
Claim 6
Dependent Claim
68 words
The process of claim 1 wherein the first etherification stage comprises a fluidized bed reaction zone for maintaining a solid particulate acid catalyst, and further including the steps of withdrawing a portion of the solid particulate catalyst from etherification production for regeneration; regenerating the solid particulate catalyst at elevated temperature to remove inactivating impurities and coke and to restore acid activity; and returning regenerated catalyst to ether production.
Claim 7
Dependent Claim
26 words
The process of claim 1 wherein the mixed olefin feedstock contains impurity selected from nitrogen compounds; Al, Fe, Na and/or Mg metal; butadiene, isoprene or cyclopentadiene.
Claim 8
Dependent Claim
25 words
The process of claim 1 wherein the first etherification reaction stage concurrently removes feedstock impurities by deposition of said impurities on said metal oxide catalyst.
Claim 9
Dependent Claim
34 words
The process of claim 1 wherein the first etherification stage comprises at least two serial reactor zones wherein a first reactor zone is maintained at least 5° C. higher than a second reactor zone.
Claim 10
Dependent Claim
26 words
The process of claim 1 wherein the second stage catalytic distillation column reaction zone operates at a temperature about 10°-30° C. lower than the first stage.
Claim 11
Dependent Claim
14 words
The process of claim 1 wherein the aliphatic alcohol comprises methanol, ethanol or isopropanol.
Claim 12
Dependent Claim
154 words
A continuous multistage process for preparing methyl tert-butyl ether comprising: maintaining two reaction zones in series arrangement, a first reaction zone containing solid crystalline acid medium pore metallosilicate catalyst particles and a second reaction zone containing acid resin catalyst; contacting a mixed feedstock comprising methanol and isobutene-containing C 4 hydrocarbons with the solid metallosilicate catalyst particles in the first reaction zone under etherification conditions to obtain an intermediate product comprising methyl t-butyl ether and unreacted feedstock; withdrawing an intermediate product stream from first reaction zone; contacting at least a portion of the intermediate product stream with acid resin catalyst in the second zone under etherification conditions to obtain a product comprising a major amount of methyl t-butyl ether. removing first reaction zone from on-line contact with feedstock; regenerating the solid catalyst particles in the first reaction zone by stripping with a non-oxidative gaseous stream; and resuming addition of feedstock to the first reaction zone.
Claim 13
Dependent Claim
154 words
A continuous multistage process for preparing methyl tert-butyl ether comprising: maintaining two reaction zones in series arrangement, a first reaction zone containing solid crystalline acid medium pore metallosilicate catalyst particles and a second reaction zone containing acid resin catalyst; contacting a mixed feedstock comprising methanol and isobutene-containing C 4 hydrocarbons with the solid metallosilicate catalyst particles in the first reaction zone under etherification conditions to obtain an intermediate product comprising methyl t-butyl ether and unreacted feedstock; withdrawing an intermediate product stream from first reaction zone; contacting at least a portion of the intermediate product stream with acid resin catalyst in the second zone under etherification conditions to obtain a product comprising a major amount of methyl t-butyl ether. removing first reaction zone from on-line contact with feedstock; regenerating the solid catalyst particles in the first reaction zone by stripping with a non-oxidative gaseous stream; and resuming addition of feedstock to the first reaction zone.
Claim 14
Dependent Claim
39 words
A process according to claim 11 further comprising the steps of withdrawing the product comprising a major amount of ether from the second reaction zone; subjecting the product to fractionation to obtain a purified ether; and recovering purified ether.
Claim 15
Dependent Claim
28 words
A process according to claim 11 wherein the solid acid catalyst particles comprise aluminosilicate zeolite having the structure of ZSM-5, ZSM-11, ZSM-12, ZSM-35, ZSM-50, MCM-22 or zeolite Beta.
Claim 16
Dependent Claim
17 words
A process according to claim 11 wherein the acid resin catalyst comprises a macroreticular polystyrenesulfonic acid catalyst.
Claim 17
Dependent Claim
175 words
A multistage process for etherifying C 4 + aliphatic hydrocarbon feedstream containing isoalkene, comprising: contacting the feedstream and lower aliphatic alcohol in a first etherification reaction stage under partial etherification conditions with a regenerable inorganic metal oxide acid solid catalyst to convert a major amount of the isoalkene to C 5 + tertiary-alkyl ether; recovering a reactant effluent from the first stage containing ether product, unreacted alcohol and unreacted olefin including isoalkene; charging the first etherification stage effluent to a second reaction stage catalytic distillation column containing at least a portion of regenerable inorganic metal oxide acid solid catalyst in a plurality of fixed bed catalysis- distillation zones to complete substantially full etherification of isoalkene; recovering C 5 + ether as a liquid from the catalytic distillation column; periodically interrupting etherification reaction in at least one reaction stage for contacting the etherification catalyst with a hot gaseous stripping stream containing hydrogen to remove feedstock impurity and coke precursor and regenerate said catalyst; and continuing ether production in the interrupted reaction stage with said regenerated catalyst.
Claim 18
Dependent Claim
175 words
A multistage process for etherifying C 4 + aliphatic hydrocarbon feedstream containing isoalkene, comprising: contacting the feedstream and lower aliphatic alcohol in a first etherification reaction stage under partial etherification conditions with a regenerable inorganic metal oxide acid solid catalyst to convert a major amount of the isoalkene to C 5 + tertiary-alkyl ether; recovering a reactant effluent from the first stage containing ether product, unreacted alcohol and unreacted olefin including isoalkene; charging the first etherification stage effluent to a second reaction stage catalytic distillation column containing at least a portion of regenerable inorganic metal oxide acid solid catalyst in a plurality of fixed bed catalysis- distillation zones to complete substantially full etherification of isoalkene; recovering C 5 + ether as a liquid from the catalytic distillation column; periodically interrupting etherification reaction in at least one reaction stage for contacting the etherification catalyst with a hot gaseous stripping stream containing hydrogen to remove feedstock impurity and coke precursor and regenerate said catalyst; and continuing ether production in the interrupted reaction stage with said regenerated catalyst.
Claim 19
Dependent Claim
38 words
The process of claim 15 wherein operating pressure is decreased in the interrupted reaction stage during stripping; and wherein the gaseous stripping stream contains hot hydrogen introduced to the reaction stage at temperature of at least 450° C.
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) | 1995-11-24 | 1996-05-25 | 1996-11-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-11-24 | 2000-05-25 | 2000-11-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-11-24 | 2004-05-25 | 2004-11-24 | $7700.00 | Window Closed / Lapsed |