The present disclosure provides a process for producing dimethyl carbonate with high conversion rate. Alkylene glycol reacts with urea via alcohylysis reaction to produce alkylene carbonate and ammonia. The alkylene carbonate produced reacts with methanol via transesterification reaction to produce dimethyl carbonate. Before the dimethyl carbonate is separated from the mixture, the nitrogen-containing impurities are substantially removed. Unreacted feedstock and catalysts are recycled in the process.

The present disclosure provides a process for producing dimethyl carbonate with high conversion rate. Alkylene glycol reacts with urea via alcohylysis reaction to produce alkylene carbonate and ammonia. The alkylene carbonate produced reacts with methanol via transesterification reaction to produce dimethyl carbonate. Before the dimethyl carbonate is separated from the mixture, the nitrogen-containing impurities are substantially removed. Unreacted feedstock and catalysts are recycled in the process.

A method manufactures diethyl carbonate by reaction distillation where transesterification and distillation are simultaneously performed in a multistage reaction distillation column provided with a catalyst introduction port and a raw material introduction port located below the catalyst introduction port, wherein: (a) the reaction is performed in a countercurrent flow format in which contact is brought about between a transesterification catalyst, dimethyl carbonate, and ethanol; (e) 1 to 250 mmol of catalyst is used per mole of dimethyl carbonate; (f) the ratio of the volume of air in the catalyst introduction port and the raw material introduction port regarding the volume of air in the reaction distillation part is 0.1 to 0.9; (g) the recirculation ratio in the reaction distillation column is 0.5 to 10; and (h) the temperature of the top part of the column and the reaction distillation part is 60 to 100 C.

The present disclosure relates to a recycling method for producing dimethyl carbonate. The process is unique in that it produces a by-product that can be re-used in the process as a raw material for repeating the process. For example, when the process is directed to synthesizing dimethyl carbonate, glycerol is used as a starting material. Glycerol is also a by-product produced during formation of dimethyl carbonate, and therefore it can be re-used as starting material to generate more dimethyl carbonate.

The present disclosure relates to a recycling method for producing dimethyl carbonate. The process is unique in that it produces a by-product that can be re-used in the process as a raw material for repeating the process. For example, when the process is directed to synthesizing dimethyl carbonate, glycerol is used as a starting material. Glycerol is also a by-product produced during formation of dimethyl carbonate, and therefore it can be re-used as starting material to generate more dimethyl carbonate.

The present disclosure relates to a recycling method for producing dimethyl carbonate and dimethyl carbonate derivatives. The process is unique in that it produces a by-product that can be re-used in the process as a raw material for repeating the process. For example, when the process is directed to synthesizing dimethyl carbonate, glycerol is used as a starting material. Glycerol is also a by-product produced during formation of dimethyl carbonate, and therefore it can be re-used as starting material to generate more dimethyl carbonate.

The present disclosure relates to a recycling method for producing dimethyl carbonate and dimethyl carbonate derivatives. The process is unique in that it produces a by-product that can be re-used in the process as a raw material for repeating the process. For example, when the process is directed to synthesizing dimethyl carbonate, glycerol is used as a starting material. Glycerol is also a by-product produced during formation of dimethyl carbonate, and therefore it can be re-used as starting material to generate more dimethyl carbonate.

The present disclosure relates to a recycling method for producing dimethyl carbonate. The process is unique in that it produces a by-product that can be re-used in the process as a raw material for repeating the process. For example, when the process is directed to synthesizing dimethyl carbonate, glycerol is used as a starting material. Glycerol is also a by-product produced during formation of dimethyl carbonate, and therefore it can be re-used as starting material to generate more dimethyl carbonate.

The present disclosure relates to a recycling method for producing dimethyl carbonate. The process is unique in that it produces a by-product that can be re-used in the process as a raw material for repeating the process. For example, when the process is directed to synthesizing dimethyl carbonate, glycerol is used as a starting material. Glycerol is also a by-product produced during formation of dimethyl carbonate, and therefore it can be re-used as starting material to generate more dimethyl carbonate.

The present invention relates to a single-pot method for preparing dialkyl carbonates, the method comprises reaction of alkylene oxide with aliphatic or cyclic aliphatic alcohol, using wood ash catalyst, under CO.sub.2 pressure and heating the reaction mixture thereof to obtain dialkyl carbonates.