To provide a method capable of separating a monofunctional species, bifunctional species, etc. of a fluorinated ether compound having a polyfluoropolyether chain and a predetermined functional group in good yield and with high separation performance.

A separation method for separating a compound represented by the formula (1) and a compound represented by the formula (2) from a mixture containing them by chromatography using a stationary phase and a mobile phase, wherein the mobile phase contains at least one type of specific solvent selected from a hydrofluoroolefin, a hydrochlorofluoroolefin, a chlorofluoroolefin, a cyclic hydrofluoroolefin, a cyclic hydrochlorofluoroolefin, a cyclic chlorofluoroolefin, a cyclic hydrofluorocarbon, a cyclic hydrochlorofluorocarbon, a cyclic chlorofluorocarbon and a perfluoroketone:

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To provide a method capable of separating a monofunctional species, bifunctional species, etc. of a fluorinated ether compound having a polyfluoropolyether chain and a predetermined functional group in good yield and with high separation performance.

A separation method for separating a compound represented by the formula (1) and a compound represented by the formula (2) from a mixture containing them by chromatography using a stationary phase and a mobile phase, wherein the mobile phase contains at least one type of specific solvent selected from a hydrofluoroolefin, a hydrochlorofluoroolefin, a chlorofluoroolefin, a cyclic hydrofluoroolefin, a cyclic hydrochlorofluoroolefin, a cyclic chlorofluoroolefin, a cyclic hydrofluorocarbon, a cyclic hydrochlorofluorocarbon, a cyclic chlorofluorocarbon and a perfluoroketone:

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The invention relates to a process wherein a dialkyl carbonate stream containing an ether alkanol impurity is subjected to extractive distillation using an extraction solvent to obtain a top stream comprising dialkyl carbonate and a bottom stream comprising the extraction solvent and the ether alkanol impurity, wherein the extraction solvent is an organic compound containing one or more hydroxyl groups and one or more ester moieties and/or ether moieties. Further, the invention relates to a process for making a diaryl carbonate, comprising reacting an aryl alcohol with a stream containing a dialkyl carbonate from which stream an ether alkanol impurity has been removed in accordance with the above-described process.

The invention relates to a process wherein a dialkyl carbonate stream containing an ether alkanol impurity is subjected to extractive distillation using an extraction solvent to obtain a top stream comprising dialkyl carbonate and a bottom stream comprising the extraction solvent and the ether alkanol impurity, wherein the extraction solvent is an organic compound containing one or more hydroxyl groups and one or more ester moieties and/or ether moieties. Further, the invention relates to a process for making a diaryl carbonate, comprising reacting an aryl alcohol with a stream containing a dialkyl carbonate from which stream an ether alkanol impurity has been removed in accordance with the above-described process.

The invention relates to a process wherein a dialkyl carbonate stream containing an ether alkanol impurity is subjected to extractive distillation using an extraction solvent to obtain a top stream comprising dialkyl carbonate and a bottom stream comprising the extraction solvent and the ether alkanol impurity, wherein the extraction solvent is an organic compound containing one or more hydroxyl groups and one or more ester moieties and/or ether moieties. Further, the invention relates to a process for making a diaryl carbonate, comprising reacting an aryl alcohol with a stream containing a dialkyl carbonate from which stream an ether alkanol impurity has been removed in accordance with the above-described process.

The present invention relates to a process for preparing an organic carbonate, comprising contacting carbon dioxide with an alcohol in the presence of water and a catalyst in a reaction zone resulting in the production of the organic carbonate, wherein the organic carbonate is continuously removed from the reaction zone.

The present invention relates to a process for preparing an organic carbonate, comprising contacting carbon dioxide with an alcohol in the presence of water and a catalyst in a reaction zone resulting in the production of the organic carbonate, wherein the organic carbonate is continuously removed from the reaction zone.

Disclosed is a distillation apparatus having a various heat exchange methods added to a process of producing dimethyl carbonate using reactive distillation and pressure-swing distillation. According to the disclosure, internal and external heat integration between a high-pressure and a low-pressure distillation column, which constitute pressure-swing distillation columns, is applied to a dimethyl carbonate production process, and a vapor recompression heat pump configured to compress and heat a fluid and transfer the heat to a fluid having a relatively low temperature is applied to achieve additional heat exchange with a reactive distillation column, thereby improving the dimethyl carbonate production process in terms of energy and economic efficiency by reducing energy consumption while reducing investment and operating costs of a reboiler and a condenser, which are required in a conventional process.

Disclosed is a distillation apparatus having a various heat exchange methods added to a process of producing dimethyl carbonate using reactive distillation and pressure-swing distillation. According to the disclosure, internal and external heat integration between a high-pressure and a low-pressure distillation column, which constitute pressure-swing distillation columns, is applied to a dimethyl carbonate production process, and a vapor recompression heat pump configured to compress and heat a fluid and transfer the heat to a fluid having a relatively low temperature is applied to achieve additional heat exchange with a reactive distillation column, thereby improving the dimethyl carbonate production process in terms of energy and economic efficiency by reducing energy consumption while reducing investment and operating costs of a reboiler and a condenser, which are required in a conventional process.

The presently claimed invention relates to a process for purification of aroma compounds by distillation. Specifically, it relates to a process for purification of carbonic esters of formula (I) using a combination of distillative processes.