Disclosed is a high yield, high selectivity and high conversion method to produce Dimethyl Carbonate (DMC) from carbon dioxide (CO.sub.2) and methanol (MeOH) using optimized concentration of ethylene oxide as water scavenger. The method provides an alternative and optimized solution towards the problem of formation of water in DMC synthesis by reporting optimal feed ratio and scavenger to MeOH feed ratio. The disclosure also discloses an optimal pressure condition that could have significant impact on economy of compression of the feed to the DMC reactor.

Disclosed is a high yield, high selectivity and high conversion method to produce Dimethyl Carbonate (DMC) from carbon dioxide (CO.sub.2) and methanol (MeOH) using optimized concentration of ethylene oxide as water scavenger. The method provides an alternative and optimized solution towards the problem of formation of water in DMC synthesis by reporting optimal feed ratio and scavenger to MeOH feed ratio. The disclosure also discloses an optimal pressure condition that could have significant impact on economy of compression of the feed to the DMC reactor.

Disclosed is a high yield, high selectivity and high conversion method to produce Dimethyl Carbonate (DMC) from carbon dioxide (CO.sub.2) and methanol (MeOH) using optimized concentration of ethylene oxide as water scavenger. The method provides an alternative and optimized solution towards the problem of formation of water in DMC synthesis by reporting optimal feed ratio and scavenger to MeOH feed ratio. The disclosure also discloses an optimal pressure condition that could have significant impact on economy of compression of the feed to the DMC reactor.

The present invention discloses a gas-liquid bubbling bed reactor, comprising a liquid distributor, a gas distributor located below the liquid distributor, a catalyst bed layer and a catalyst support plate, and an optional interception screen, wherein the top of the reactor is provided with a gas outlet, the reactor is provided with a feed inlet connected to the liquid distributor, a gas inlet connected to the gas distributor, the bottom is provided with a discharge outlet. The present invention further provides a reaction system, which comprises the gas-liquid bubbling bed reactor as the main reactor and a sub-reactor. Through the system and the process of the present invention, the problems of the low conversion rate, the gas binding of the circulating pump, the unstable operation, the low yield of electronic-grade products, and the like in the carbonate synthesis process are solved purposedly targetedly, and the present invention can be applied to related industrial production.

The present invention discloses a gas-liquid bubbling bed reactor, comprising a liquid distributor, a gas distributor located below the liquid distributor, a catalyst bed layer and a catalyst support plate, and an optional interception screen, wherein the top of the reactor is provided with a gas outlet, the reactor is provided with a feed inlet connected to the liquid distributor, a gas inlet connected to the gas distributor, the bottom is provided with a discharge outlet. The present invention further provides a reaction system, which comprises the gas-liquid bubbling bed reactor as the main reactor and a sub-reactor. Through the system and the process of the present invention, the problems of the low conversion rate, the gas binding of the circulating pump, the unstable operation, the low yield of electronic-grade products, and the like in the carbonate synthesis process are solved purposedly targetedly, and the present invention can be applied to related industrial production.

A method and system for membrane-assisted production of high purity concentrated dimethyl carbonate by the reaction of carbon dioxide and methanol is provided. Carbon dioxide is recovered from flue gas or other dilute streams from industrial processes by a membrane and subsequent conversion takes place to an intermediate methyl carbamate by reacting of carbon dioxide with ammonia and methanol. For high-purity carbon dioxide obtained by one of the carbon capture technologies or by a process (such as, for example, ethanol fermentation process) the membrane reactor is replaced with a catalytic reactor for direct conversion of carbon dioxide to methyl carbamate by reacting with ammonia and methanol. The methyl carbamate is further reacted with methanol for conversion to dimethyl carbonate. An integrated reactive distillation process using side reactors is used for facilitating the catalytic reaction in the subject method for producing high purity dimethyl carbonate.

A method and system for membrane-assisted production of high purity concentrated dimethyl carbonate by the reaction of carbon dioxide and methanol is provided. Carbon dioxide is recovered from flue gas or other dilute streams from industrial processes by a membrane and subsequent conversion takes place to an intermediate methyl carbamate by reacting of carbon dioxide with ammonia and methanol. For high-purity carbon dioxide obtained by one of the carbon capture technologies or by a process (such as, for example, ethanol fermentation process) the membrane reactor is replaced with a catalytic reactor for direct conversion of carbon dioxide to methyl carbamate by reacting with ammonia and methanol. The methyl carbamate is further reacted with methanol for conversion to dimethyl carbonate. An integrated reactive distillation process using side reactors is used for facilitating the catalytic reaction in the subject method for producing high purity dimethyl carbonate.

Realized is a method for restoring the activity of a catalyst for producing a carbonate ester by a simple technique with no use of a complicated step such as calcining or the like to allow the catalyst to be reusable, and a method for producing a carbonate ester at a high yield by use of the catalyst thus regenerated. The above-described problem has been solved by a method for regenerating a catalyst containing CeO.sub.2, the catalyst being usable for a carbonate ester generation reaction of generating a carbonate ester from carbon dioxide and an alcohol, the method comprising (a) a separation step of separating the catalyst as a crude catalyst from a reaction solution of carbon dioxide and the alcohol; and (b) a catalyst processing step of washing the crude catalyst with a washing alcohol to provide a purified catalyst.

Realized is a method for restoring the activity of a catalyst for producing a carbonate ester by a simple technique with no use of a complicated step such as calcining or the like to allow the catalyst to be reusable, and a method for producing a carbonate ester at a high yield by use of the catalyst thus regenerated. The above-described problem has been solved by a method for regenerating a catalyst containing CeO.sub.2, the catalyst being usable for a carbonate ester generation reaction of generating a carbonate ester from carbon dioxide and an alcohol, the method comprising (a) a separation step of separating the catalyst as a crude catalyst from a reaction solution of carbon dioxide and the alcohol; and (b) a catalyst processing step of washing the crude catalyst with a washing alcohol to provide a purified catalyst.

Realized is a method for restoring the activity of a catalyst for producing a carbonate ester by a simple technique with no use of a complicated step such as calcining or the like to allow the catalyst to be reusable, and a method for producing a carbonate ester at a high yield by use of the catalyst thus regenerated. The above-described problem has been solved by a method for regenerating a catalyst containing CeO.sub.2, the catalyst being usable for a carbonate ester generation reaction of generating a carbonate ester from carbon dioxide and an alcohol, the method comprising (a) a separation step of separating the catalyst as a crude catalyst from a reaction solution of carbon dioxide and the alcohol; and (b) a catalyst processing step of washing the crude catalyst with a washing alcohol to provide a purified catalyst.