Process for preparing aromatic carbonate

The aryl carbonate or its mixture is obtained by the transesterification of continuous fed dialkyl carbonate, alkylaryl carbonate or their mixture and aromatic hydroxyl compound, alkylaryl carbonate or their mixture in the presence of the catalyst in a continuous multistage distilling tower. The higher b.p. liquid product withdrawn from the bottom of the towern is aryl carbonate or its mixture. The lower b.p. by-product is removed from the upper tower. Aryl carbonate is used as raw material for the preparation of polycarbonate or isocyanates. The process has advantages of enhanded product yield, higher selection, high production speed and no need of toxic phosgene.