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US4664753A Expired / Lapsed US ⏱️ 0.0 years remaining

Process for separating iodine and its compounds from the carbonylation products obtained by subjecting dimethylether, methyl acetate or methanol to a carbonylation reaction

Assignee: Hoechst AG
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Filing: 1984-08-06
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Granted: 1987-05-12
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Expires: 2004-08-06
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Abstract

Abstract The disclosure relates to a process for separating iodine and its compounds from the carbonlyation products acetic acid, acetic anhydride or ethylidene diacetate obtained by subjecting dimethylether, methyl acetate or methanol to a carbonylation reaction. For reducing the quantity of total iodine contaminating the carbonlyation products to less than 20 ppb iodine, the disclosure provides for the carbonylation products to be treated at temperatures of 20° to 250° C. with an alkyl or aryl phosphine or a heterocyclic aromatic nitrogen compound and at least one of the metals copper, silver, zinc or cadmium or their compounds and to be distillatively separated from the iodine thereby fixed in non-volatile form.

Inventors

  • 👤 Heinz Erpenbach
  • 👤 Klaus Gehrmann
  • 👤 Winfried Lork
  • 👤 Peter Prinz

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-08 19:12
CPC Classifications
C; C07; C07C; C07C51/00; C07C51/42; C07C51/487; C07C51/43; C07C51/44; C07C67/00; C07C67/48; C07C67/60

Claims Analysis

Total Claims: 9
Claim 1
Independent Claim 103 words
A process for separating iodine and its compounds from the carbonylation products acetic acid, acetic anhydride or ethylidene diacetate obtained by subjecting dimethylether, methyl acetate or methanol to a carbonylation reaction, which process comprises: reducing the quantity of total iodine contaminating the carbonylation products to less than 20 ppb iodine by treating the carbonylation products at temperatures of 20° to 250° C. with an alkyl or aryl phosphine or a heterocyclic aromatic nitrogen compound and at least one of the metals copper, silver, zinc or cadmium or their compounds and distillatively separating the carbonylation products from the iodine thereby fixed in non-volatile form.
Claim 2
Dependent Claim 103 words
A process for separating iodine and its compounds from the carbonylation products acetic acid, acetic anhydride or ethylidene diacetate obtained by subjecting dimethylether, methyl acetate or methanol to a carbonylation reaction, which process comprises: reducing the quantity of total iodine contaminating the carbonylation products to less than 20 ppb iodine by treating the carbonylation products at temperatures of 20° to 250° C. with an alkyl or aryl phosphine or a heterocyclic aromatic nitrogen compound and at least one of the metals copper, silver, zinc or cadmium or their compounds and distillatively separating the carbonylation products from the iodine thereby fixed in non-volatile form.
Claim 3
Dependent Claim 19 words
A process as claimed in claim 1, wherein carbonylation products containing less than 500 ppm total iodine are used.
Claim 4
Dependent Claim 33 words
A process as claimed in claim 1, wherein the said treating of the carbonylation products is carried out at temperatures of 100° to 140° C. over a period of 15 to 120 minutes.
Claim 5
Dependent Claim 36 words
A process as claimed in claim 1, wherein a ratio by weight of iodine(-compound) to alkyl- or aryl phosphine or nitrogen compound to metal(-compound) of 1:(100-10 000):(50-10 000) is established in the mixture to be treated.
Claim 6
Dependent Claim 22 words
A process as claimed in claim 1, wherein said treating of the carbonylation products is carried out in the presence of hydrogen.
Claim 7
Dependent Claim 27 words
A process as claimed in claim 1, wherein the aryl phosphine is triphenylphosphine, and the heterocyclic aromatic nitrogen compound is pyridine, N-methylimidazole, 3-picoline, 2,4-lutidine, 3,4-lutidine, or quinoline.
Claim 8
Dependent Claim 32 words
A process as claimed in claim 1, wherein the metal or metal compound is (a) metallic zinc or (b) an acetate, an oxide, or an acetyl acetonate of copper, cadmium or silver.
Claim 9
Dependent Claim 18 words
A process as claimed in claim 7, wherein the phosphine is triphenyl-phosphine and the metal compound is copper(II)acetate.

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1990-05-11 1990-11-10 1991-05-12 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1994-05-11 1994-11-10 1995-05-12 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1998-05-11 1998-11-10 1999-05-12 $7700.00 Window Closed / Lapsed

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