| 摘要 |
The invention aims at providing a specific process for producing high-purity diphenyl carbonate, which is necessary in producing high-quality and high-performance aromatic polycarbonates, from cyclic carbonates and phenol stably on an industrial scale (e.g., in an amount of one ton or above per hour) over a long period (e.g., for 1000 hours or longer, preferably 3000 hours or longer, still preferably 5000 hours or longer). The aim can be attained by a process for producing high-purity diphenyl carbonate necessary for the production of high-quality and high -performance aromatic polycarbonates from cyclic carbonates and phenol which comprises the step (I) of producing a dialkyl carbonate and a diol by use of a reaction-distillation column having a specific structure, the step (II) of producing diphenyl carbonate by use of two reaction-distillation columns having specific structures, and the step (III) of passing the diphenyl carbonate through a column (A) for separating high-boiling substances and a column (B) for purifying diphenyl carbonate to obtain high-purity diphenyl carbonate. |
