Patent US4467126A successfully refreshed from Google Patents.
US4467126A
Expired / Lapsed
US
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Process for the separation of di-substituted benzene
Assignee: Honeywell UOP LLC
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Filing: 1983-07-18
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Granted: 1984-08-21
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Expires: 2003-07-18
Abstract
Abstract An adsorptive separation process for separating the para-isomers of a di-substituted benzene from a feed mixture comprising the para-isomer and at least one other isomer. One substituted group is NO 2 -- and the other group is a normal hydrocarbon having less than 6 carbon atoms per molecule, the halogens, NH 2 --, NO 2 -- or C.tbd.N--. The process comprises contacting the feed mixture with an adsorbent comprising crystalline silica having a silica/alumina mole ratio of at least 12, selectively adsorbing substantially all of the para-isomer to the substantial exclusion of the remaining isomers and thereafter recovering high-purity para-isomer by means of desorption with an appropriate desorbent material.
Inventors
- 👤 Hermann A. Zinnen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 20:57
CPC Classifications
C; C07; C07C; C07C201/00; C07C201/06; C07C201/16
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
136 words
A process for separating the para-isomer of a di-substituted benzene, one substituted group being NO 2 --and the other substituted group being selected from the group consisting of normal hydrocarbons having less than 6 carbon atoms per molecule, the halogens, NH 2 --, NO 2 --and C.tbd.N-- from a feed mixture comprising said para-isomer and at least one other isomer of said di-substituted benzene, which process comprises contacting at adsorption conditions said mixture with an adsorbent comprising crystalline silica having a silica/alumina mole ratio of at least 12 , selectively adsorbing said para-isomer to the substantial exclusion of the remaining isomers, removing the remaining isomers from said adsorbent and thereafter recovering high-purity paraisomer by desorption with a desorbent material comprising a nitrile or nitro-substituted monocyclic aromatic or alkane in mixture with a monocyclic aromatic carrier material.
Claim 2
Dependent Claim
136 words
A process for separating the para-isomer of a di-substituted benzene, one substituted group being NO 2 --and the other substituted group being selected from the group consisting of normal hydrocarbons having less than 6 carbon atoms per molecule, the halogens, NH 2 --, NO 2 --and C.tbd.N-- from a feed mixture comprising said para-isomer and at least one other isomer of said di-substituted benzene, which process comprises contacting at adsorption conditions said mixture with an adsorbent comprising crystalline silica having a silica/alumina mole ratio of at least 12 , selectively adsorbing said para-isomer to the substantial exclusion of the remaining isomers, removing the remaining isomers from said adsorbent and thereafter recovering high-purity paraisomer by desorption with a desorbent material comprising a nitrile or nitro-substituted monocyclic aromatic or alkane in mixture with a monocyclic aromatic carrier material.
Claim 3
Dependent Claim
21 words
The process of claim 1 wherein said feed mixture comprises para-nitrotoluene and at least one of the isomers, meta-nitrotoluene, and ortho-nitrotoluene.
Claim 4
Dependent Claim
25 words
The process of claim 1 further characterized in that said desorbent material has an average boiling point substantially different from that of the feed mixture.
Claim 5
Dependent Claim
16 words
The process of claim 2 wherein said desorbent material comprises a mixture of nitrobenzene and toluene.
Claim 6
Dependent Claim
16 words
The process of claim 2 wherein said desorbent material comprises a mixture of acetonitrile and mesitylene.
Claim 7
Dependent Claim
16 words
The process of claim 2 wherein said desorbent material comprises a mixture of nitromethane and mesitylene.
Claim 8
Dependent Claim
21 words
The process of claim 1 wherein said feed mixture comprises para-chloronitrobenzene and at least one of the isomers meta-chloronitrobenzene and ortho-chloronitrobenzene.
Claim 9
Dependent Claim
13 words
The process of claim 7 wherein said desorbent material comprises butyronitrile and mesitylene.
Claim 10
Dependent Claim
36 words
The process of claim 1 further characterized in that said adsorption conditions include a temperature within the range of from about 40° C. to about 230° C. and at a pressure sufficient to maintain liquid phase.
Claim 11
Dependent Claim
17 words
The process of claim 1 wherein said process is effected by a simulated moving bed flow system.
References Cited (Backward Citations)
US2985589A
Cited
US3114782A
Cited
US3201491A
Cited
US3558732A
Cited
US3668267A
Cited
US3686342A
Cited
US3997620A
Cited
US4240986A
Cited
US4234520A
Cited
US4270013A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-08-21 | 1988-02-20 | 1988-08-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-08-21 | 1992-02-20 | 1992-08-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-08-21 | 1996-02-20 | 1996-08-21 | $7700.00 | Window Closed / Lapsed |