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Process for the manufacture of o-toluidine and/or m-toluidine and/or p-toluidine

Assignee: Hoechst AG
•
Filing: 1983-04-12
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Granted: 1984-10-30
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Expires: 2003-04-12
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Abstract

Abstract The invention provides a process for the manufacture of o-toluidine and/or m-toluidine and/or p-toluidine, which comprises the two following steps (a) and (b): (a) treatment of a toluidine isomer mixture or of the not intended toluidine isomer or of one of the not intended toluidine isomers with an isomerization catalyst selected from the group of synthetic zeolites of the pentasil type, (b) isolation of the intended isomer or one of the intended isomers from the isomer mixture formed in step (a) by selective adsorption to a medium-pore or large-pore zeolite and subsequent desorption, furthermore discharge of the isolated isomer and recycling of the remaining isomer mixture to step (a).

Inventors

  • 👤 Hans-J/u/ rgen Arpe
  • 👤 Heinz Litterer

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-01 17:58
CPC Classifications
C; C07; C07C; C07C209/00; C07C209/68

Claims Analysis

Total Claims: 16
Claim 1
Independent Claim 117 words
A process for the manufacture of at least one member selected from the group consisting of o-toluidine m-toluidine and p-toluidine, which comprises (a) treating, at a temperature of from 250° to 500° C., a first charge containing at least one toluidine isomer other than a toluidine isomer sought to be isolated, with an isomerization catalyst selected from the group of synthetic zeolites of the pentasil type, the ions of which are exchanged, to form a second charge, (b) isolating the desired toluidine isomer from the second charge by selective adsorption to an X or Y zeolite, the ions of which are exchanged, and subsequent desorption, and (c) recycling the balance of the second charge to step (a).
Claim 2
Dependent Claim 117 words
A process for the manufacture of at least one member selected from the group consisting of o-toluidine m-toluidine and p-toluidine, which comprises (a) treating, at a temperature of from 250° to 500° C., a first charge containing at least one toluidine isomer other than a toluidine isomer sought to be isolated, with an isomerization catalyst selected from the group of synthetic zeolites of the pentasil type, the ions of which are exchanged, to form a second charge, (b) isolating the desired toluidine isomer from the second charge by selective adsorption to an X or Y zeolite, the ions of which are exchanged, and subsequent desorption, and (c) recycling the balance of the second charge to step (a).
Claim 3
Dependent Claim 20 words
A process as recited in claim 1, wherein the temperature of the treating step is from 300° to 450° C.
Claim 4
Dependent Claim 43 words
A process as recited in claim 1, wherein the exchanged ions are cations selected from the group consisting of Na.sup.(+), H.sup.(+), NH 4 .sup.(+), Be 2 (+), Mg 2 (+), Ca 2 (+) and rare earth metal ions, or combinations of these cations.
Claim 5
Dependent Claim 119 words
A process for the manufacture of at least one member selected from the group consisting of o-toluidine, m-toluidine and p-toluidine, which comprises (a) treating, at a temperature of from 250° to 500° C., a first charge containing at least one toluidine isomer other than a toluidine isomer sought to be isolated, with an isomerization catalyst selected from the group of synthetic zeolites of the X or Y type, the ions of which are exchanged, to form a second charge, (b) isolating the desired toluidine isomer from the second charge by selective adsorption to an X or Y zeolite, the ions of which are exchanged, and subsequent desorption, and (c) recycling the balance of the second charge to step (a).
Claim 6
Dependent Claim 119 words
A process for the manufacture of at least one member selected from the group consisting of o-toluidine, m-toluidine and p-toluidine, which comprises (a) treating, at a temperature of from 250° to 500° C., a first charge containing at least one toluidine isomer other than a toluidine isomer sought to be isolated, with an isomerization catalyst selected from the group of synthetic zeolites of the X or Y type, the ions of which are exchanged, to form a second charge, (b) isolating the desired toluidine isomer from the second charge by selective adsorption to an X or Y zeolite, the ions of which are exchanged, and subsequent desorption, and (c) recycling the balance of the second charge to step (a).
Claim 7
Dependent Claim 20 words
A process as recited in claim 4, wherein the temperature of the treating step is from 300° to 450° C.
Claim 8
Dependent Claim 43 words
A process as recited in claim 4, wherein the exchanged ions are cations selected from the group consisting of Na.sup.(+), N.sup.(+), NH 4 .sup.(+), Be 2 (+), Mg 2 (+), Ca 2 (+) and rare earth metal ions, or combinations of these cations.
Claim 9
Dependent Claim 101 words
A process for the manufacture of at least one member from the group consisting of o-toluidine, m-toluidine and p-toluidine, which comprises (c) isolating a desired toluidine isomer from a first charge by selective adsorption to an X or Y zeolite, the ions of which are exchanged, and subsequent desorption, (d) treating, at a temperature of from 250° to 500° C., the balance of the first charge with an isomerization catalyst selected from the group of synthetic zeolites of the pentasil type, the ions of which are exchanged, to form a second charge, and (e) recycling the second charge to step (c).
Claim 10
Dependent Claim 101 words
A process for the manufacture of at least one member from the group consisting of o-toluidine, m-toluidine and p-toluidine, which comprises (c) isolating a desired toluidine isomer from a first charge by selective adsorption to an X or Y zeolite, the ions of which are exchanged, and subsequent desorption, (d) treating, at a temperature of from 250° to 500° C., the balance of the first charge with an isomerization catalyst selected from the group of synthetic zeolites of the pentasil type, the ions of which are exchanged, to form a second charge, and (e) recycling the second charge to step (c).
Claim 11
Dependent Claim 20 words
A process as recited in claim 7, wherein the temperature of the treating step is from 300° to 450° C.
Claim 12
Dependent Claim 43 words
A process as recited in claim 7, wherein the exchanged ions are cations selected from the group consisting of Na.sup.(+), H.sup.(+), NH 4 .sup.(+), Be 2 (+), Mg 2 (+), Ca 2 (+) and rare earth metal ions, or combinations of these cations.
Claim 13
Dependent Claim 103 words
A process for the manufacture of at least one member from the group consisting of o-toluidine, m-toluidine and p-toluidine, which comprises (c) isolating a desired toluidine isomer from a first charge by selective adsorption to an X or Y zeolite, the ions of which are exchanged, and subsequent desorption, (d) treating, at a temperature of from 250° to 500° C., the balance of the first charge with an isomerization catalyst selected from the group of synthetic zeolites of the X or Y type, the ions of which are exchanged, to form a second charge, and (e) recycling the second charge to step (c).
Claim 14
Dependent Claim 103 words
A process for the manufacture of at least one member from the group consisting of o-toluidine, m-toluidine and p-toluidine, which comprises (c) isolating a desired toluidine isomer from a first charge by selective adsorption to an X or Y zeolite, the ions of which are exchanged, and subsequent desorption, (d) treating, at a temperature of from 250° to 500° C., the balance of the first charge with an isomerization catalyst selected from the group of synthetic zeolites of the X or Y type, the ions of which are exchanged, to form a second charge, and (e) recycling the second charge to step (c).
Claim 15
Dependent Claim 20 words
A process as recited in claim 10, wherein the temperature of the treating step is from 300° to 450° C.
Claim 16
Dependent Claim 43 words
A process as recited in claim 10, wherein the exchanged ions are cations selected from the group consisting of Na.sup.(+), H.sup.(+), NH 4 .sup.(+), Be 2 (+), Mg 2 (+), Ca 2 (+) and rare earth metal ions, or combinations of these cations.

References Cited (Backward Citations)

US3069470A Cited
US4181811A Cited
US4371721A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1987-10-30 1988-04-30 1988-10-30 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1991-10-30 1992-04-30 1992-10-30 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1995-10-30 1996-04-30 1996-10-30 $7700.00 Window Closed / Lapsed

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