摘要 |
<p>A process for the preparation of aromatic carbonates by transesterification of a starting substance selected from the group consisting of dialkyl carbonates, alkyl aryl carbonates and mixtures of both with a reactant selected from the group consisting of aromatic monohydroxyl compounds, alkyl aryl carbonates and mixtures of both in the presence of a metal catalyst, which comprises reacting part of the high-boiling reaction mixture of the transesterification containing the objective aromatic carbonate and the catalyst or part of the residue remaining after the recovery of the objective aromatic carbonate from the reaction mixture, which contains a high-boiling substance (A) having a higher boiling point than that of the objective aromatic carbonate and the catalyst (B), with a reactant (C) reactive with at least either of the substance (A) and the catalyst (B), and discharging the product of reaction of (A) with (C) from the production system of the aromatic carbonate with the product of reaction of (B) with (C) recycled into the reaction system. This process permits stable preparation of high-purity aromatic carbonates for a prolonged period.</p> |