Process for the preparation of phenyl carbonates or polycarbonates
AssigneeThe Dow Chemical Company
InventorsHendrik Tuinstra, Cynthia L. Rand
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Abstract
A process for the preparation of an aromatic carbonate or polycarbonate from a phenol or bisphenol, methanol, carbon monoxide and oxygen comprising the steps of 1) reacting phenol or bisphenol with acetic anhydride to form (bis)phenyl acetate; 2) reacting dimethyl carbonate with (bis)phenyl acetate from step 1 to produce a phenyl carbonate or polycarbonate and methyl acetate; and 3) reacting the methyl acetate with carbon monoxide to produce acetic anhydride for use in step 1. In a desirable embodiment the dimethyl carbonate may also be prepared by reaction of methanol, carbon monoxide and oxygen.
Claims6
A process for producing a phenyl carbonate comprising the steps of:
- A. reacting acetic anhydride with a phenol to produce a phenyl acetate and acetic acid;
- B. reacting dimethyl carbonate with at least a portion of the phenyl acetate from step A to produce a phenyl carbonate and methyl acetate;
- C. separating the phenyl carbonate and methyl acetate;
- D. reacting the methyl acetate with carbon monoxide in the presence of a catalyst to prepare acetic anhydride;
- and
- E. recycling the acetic anhydride from step D as a least a portion of the acetic anhydride reactant of step A.
Dependencies are inferred from the claim text.