Process for the preparation of acetic anhydride
AssigneeHalcon Research and Development Corp.
InventorJoseph Pugach
Life of this patent
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Abstract
Acetic anhydride is prepared from methyl acetate and/or dimethyl ether in carbonylation processes comprising the use of a halide, carbon monoxide and a Group VIII noble metal in the presence of promoters comprising metallic hafnium and an organo-phosphorus compound or an organo-nitrogen compound wherein the phosphorus and nitrogen are trivalent, or an arsine of the formula: ##STR1## wherein R and R.sup.1 are monocyclic aryl groups or alkyl groups and R.sup.2 is the radical ##STR2## a monocyclic aryl group or an alkyl group, and wherein R.sup.3 and R.sup.4 are each a monocyclic aryl group or an alkyl group, n being zero or a digit from 1-20.
Claims5
A process for the preparation of acetic anhydride which comprises reacting carbon monoxide, a halide which is an iodide or bromide and a compound selected from the group consisting of a methyl acetate and dimethyl ether under substantially anhydrous conditions in the presence of 1 to 75 weight percent acetic acid, in the presence of a Group VIII noble metal catalyst and in the presence of a multiple promoter comprising metallic hafnium, and an organo-phosphorus compound or an organo-nitrogen compound wherein the phosphorus and nitrogen are trivalent, or an arsine of the formula:
- ##STR8## wherein R and R.sup.1 are monocyclic aryl groups or alkyl groups and R.sup.2 is the radical ##STR9## a monocyclic aryl group or an alkyl group, and wherein R.sup.3 and R.sup.4 are each a monocyclic aryl group or an alkyl group, n being zero or a digit from 1-20.
Dependencies are inferred from the claim text.