Phenol → Diphenyl carbonate

Beteiligte Stoffe

Reaktionsschritte

An apparatus comprising two continuous multi-stage distillation columns as shown in FIG. 3 was employed. Reaction was performed by continuously feeding in a liquid form a mixture of dimethyl carbonate, phenol and Catalyst A to first continuous multi-stage distillation column 1' at a position 1 m below top 17 thereof, which column was comprised of a packed column of 4 m in height and 3 inches in diameter and packed with stainless steel-made Dixon packing (diameter: about 6 mm), from material feeding pipe 2 through conduit 4, preheater 5 and conduit 6, thereby allowing the mixture to flow down the inside of the first continuous multi-stage distillation column. The thermal energy necessary for reaction and distillation was supplied by circulating the column bottom liquid through conduits 8 and 9, reboiler 10 where heating was effected and conduit 11. The gas continuously distilled from column top 17 was led through conduit 12 to condenser 13 where the gas was condensed. A portion of the resultant condensate was recycled to first continuous multi-stage distillation column 1, through conduits 14 and 15 and the rest of the condensate was continuously withdrawn through conduit 16. From the withdrawn condensate, a low boiling point component containing methanol which was a low boiling point reaction product was obtained. A high boiling point component containing the catalyst component and methyl phenyl carbonate was continuously withdrawn from column bottom 18 through conduits 8 and 19.

Herkunft & Nachweise