Patent ID: 7799939

Claim:
In a process for continuous production of a dialkyl carbonate and a diol, by continuously feeding a first starting material containing a cyclic carbonate as a main component thereof and a second starting material containing an aliphatic monohydric alcohol as a main component thereof into a tray column type continuous multi-stage distillation column, bringing the starting materials into contact with a catalyst present in said distillation column so as to bring about reaction in a tray portion and a column bottom portion, continuously withdrawing a low boiling point component containing a produced dialkyl carbonate from an upper portion of said distillation column, and continuously withdrawing a high boiling point component containing a produced diol from a lower portion of said distillation column, wherein the improvement comprises: the following formula (1) being satisfied, 780≦α+1.24×β≦5150 (1), wherein α=θ 1 0.52 ×(T 1 +120) 1.2 , β=θ 2 0.52 ×(T 2 +120) 1.2 , θ 1 (hours) is an average residence time of the reaction liquid in the tray portion of said distillation column in which the catalyst is present; T 1 (° C.) is a temperature at a (n/2) th stage (a ((n+1)/2) th stage in the case that n is odd) from the top of the tray portion in which the catalyst is present wherein n is a total number of stages therein; θ 2 (hours) is an average residence time of the reaction liquid in the column bottom portion of said distillation column; and T 2 (° C.) is a temperature in the column bottom portion.