Abstract: A method for producing a dialkyl carbonate and a diol, comprising: (a) effecting a transesterification reaction between a cyclic carbonate and an aliphatic monohydric alcohol in the presence of a transesterification catalyst, thereby obtaining a reaction mixture containing a product dialkyl carbonate and a product diol, (b) withdrawing a dialkyl carbonate-containing liquid from the reaction mixture, followed by separation of the dialkyl carbonate from the dialkyl carbonate-containing liquid, and (c) withdrawing a diol-containing liquid from the reaction mixture, followed by separation of the diol from the diol-containing liquid, wherein the cyclic carbonate contains a cyclic ether in an amount of from 0.1 to 3,000 ppm by weight, and the product dialkyl carbonate contains a carbonate ether of not more than 10,000 ppm by weight.

Abstract: The invention provides an apparatus and process for producing a diol by taking a cyclic carbonate and an aliphatic monohydric alcohol as starting materials, continuously feeding the starting materials into column A, carrying out reactive distillation in column A, continuously withdrawing a low boiling point reaction mixture containing a produced dialkyl carbonate and the aliphatic monohydric alcohol from an upper portion of column A, continuously withdrawing a high boiling point reaction mixture containing a produced diol from a lower portion of column A, continuously feeding the high boiling point reaction mixture into distillation column C, distilling off material having a lower boiling point than that of the diol contained in the high boiling point reaction mixture as a column top component and a side cut component so as to obtain a column bottom component, continuously feeding the column bottom component into column C, and obtaining the diol.

Abstract: The invention provides an apparatus and process for producing high-purity diol by taking cyclic carbonate and aliphatic monohydric alcohol as starting materials, continuously feeding the starting materials into column A, carrying out reactive distillation in column A, continuously withdrawing a low boiling point reaction mixture containing a produced dialkyl carbonate and the aliphatic monohydric alcohol from an upper portion of column A, continuously withdrawing a high boiling point reaction mixture containing a produced diol from a lower portion of column A, continuously feeding the high boiling point reaction mixture into distillation column C, distilling off material having a lower boiling point than that of the diol contained in the high boiling point reaction mixture AB as a column top component and/or a side cut component so as to obtain a column bottom component, continuously feeding the column bottom component into distillation column E, and obtaining the diol.

Abstract: A process for industrially producing dialkyl carbonate and a diol continuously through a reactive distillation system is disclosed. The process includes the steps of taking a cyclic carbonate and an aliphatic monohydric alcohol as starting materials, continuously feeding the starting materials into a continuous multi-stage distillation column in which a catalyst is present, carrying out reaction and distillation simultaneously in the column, continuously withdrawing a low boiling point reaction mixture containing the produced dialkyl carbonate from an upper portion of the column in a gaseous form, and continuously withdrawing a high boiling point reaction mixture containing the diol from a lower portion of the column in a liquid form. According to the present invention, there is provided a specific continuous multi-stage distillation column having a specified structure, and a production process using this continuous multi-stage distillation column.

Abstract: It is an object of the present invention to provide a specific apparatus and process for using a single distillation column on a low boiling point reaction mixture containing a large amount of a dialkyl carbonate and an aliphatic monohydric alcohol produced through a reactive distillation process of taking a cyclic carbonate and the aliphatic monohydric alcohol as starting materials, continuously feeding the starting materials into a continuous multi-stage distillation column in which a homogeneous catalyst is present, and carrying out reaction and distillation simultaneously in the column, so as to separate the low boiling point reaction mixture by distillation into a column top component BT having the aliphatic monohydric alcohol as a main component thereof and a column bottom component BB having the dialkyl carbonate as a main component thereof stably for a prolonged period of time industrially.

Abstract: A high-purity diphenyl carbonate, wherein the diphenyl carbonate is unsubstituted or substituted with a lower hydrocarbon, and has a halogen content of not more than 0.1 ppm, a content of an intermediate boiling point material of not more than 100 ppm, and a content of by-products having a higher boiling point than that of said diphenyl carbonate of not more than 100 ppm. A specific industrially useful process for the production of a high-purity diaryl carbonate in which a diaryl carbonate having low contents of intermediate boiling point and high boiling point impurities is produced is disclosed. As a starting material, a reaction mixture containing an alkyl aryl carbonate obtained through a transesterification reaction between a dialkyl carbonate and an aromatic monohydroxy compound is used. The process in which separation by distillation is carried out uses three distillation columns in a specified order.

Abstract: An aromatic polycarbonate that is obtained by transesterification between a high-purity diphenyl carbonate and an aromatic dihydroxy compound. A specific industrially useful process for the production of a high-purity diaryl carbonate in which a diaryl carbonate having low contents of intermediate boiling point and high boiling point impurities is produced is disclosed. As a starting material, a reaction mixture containing an alkyl aryl carbonate obtained through a transesterification reaction between a dialkyl carbonate and an aromatic monohydroxy compound is used. The process in which separation by distillation is carried out uses three distillation columns in a specified order. Moreover, it is particularly preferable if a reactive distillation column and the three distillation columns, each of which has a specified structure, and the three distillation columns are each operated under specified distillation conditions.

Abstract: A process for producing an aromatic carbonate, which comprises the steps of: (I) transesterifying a starting material selected from the group consisting of a dialkyl carbonate, an alkyl aryl carbonate and a mixture thereof with a reactant selected from the group consisting of an aromatic monohydroxy compound, an alkyl aryl carbonate and a mixture thereof, in the presence of a catalyst, to thereby obtain a high boiling point reaction mixture comprising an aromatic carbonate (a) and an aromatic carbonate ether (b), while withdrawing a low boiling point reaction mixture containing a low boiling point by-product; and (II) separating the aromatic carbonate ether (b) from the high boiling point reaction mixture to thereby obtain a high purity aromatic carbonate.

Abstract: It is an object of the present invention to provide a specific industrial separation process that enables an alcohol to be separated out efficiently and stably for a prolonged period of time from a large amount of a low boiling point reaction mixture containing a by-produced alcohol when mass-producing aromatic carbonates on an industrial scale by subjecting a dialkyl carbonate and an aromatic monohydroxy compound to transesterification reaction in a reactive distillation column in which a catalyst is present. Although there have been various proposals regarding processes for the production of aromatic carbonates by means of a reactive distillation method, these have all been on a small scale and short operating time laboratory level, and there have been no disclosures whatsoever on a specific process or apparatus enabling mass production on an industrial scale to be carried out stably for a prolonged period of time.

Abstract: According to the present invention, there are provided a high boiling point material separating column A and a diphenyl carbonate purifying column B each comprising a continuous multi-stage distillation column having specified structures, and there is provided a specific process that enables a high-purity diphenyl carbonate which is important as a raw material of a high-quality and high-performance polycarbonate to be produced stably for a prolonged period of time on an industrial scale of not less than 1 ton/hr from a reaction mixture containing the diphenyl carbonate using an apparatus in which these two continuous multi-stage distillation columns are connected together.

Abstract: It is an object of the present invention to provide, for a case of producing a dialkyl carbonate and a diol from a cyclic carbonate and an aliphatic monohydric alcohol, a process that simultaneously satisfies the cyclic carbonate conversion being high, the selectivities for the dialkyl carbonate and diol to be produced being high, and a high-purity diol having a high UV transmittance and a low aldehyde content being obtained without carrying out complicated treatment such as feeding water into a diol distillation purification step.

Abstract: A method for producing a dialkyl carbonate and a diol, comprising: (a) effecting a transesterification reaction between a cyclic carbonate and an aliphatic monohydric alcohol in the presence of a transesterification catalyst, thereby obtaining a reaction mixture containing a product dialkyl carbonate and a product diol, (b) withdrawing a dialkyl carbonate-containing liquid from the reaction mixture, followed by separation of the dialkyl carbonate from the dialkyl carbonate-containing liquid, and (c) withdrawing a diol-containing liquid from the reaction mixture, followed by separation of the diol from the diol-containing liquid, wherein the cyclic carbonate contains a cyclic ether in an amount of from 0.1 to 3,000 ppm by weight, and the product dialkyl carbonate contains a carbonate ether of not more than 10,000 ppm by weight.

Abstract: A method for producing a dialkyl carbonate and a diol, comprising: (a) effecting a transesterification reaction between a cyclic carbonate and an aliphatic monohydric alcohol in the presence of a transesterification catalyst, thereby obtaining a reaction mixture containing a product dialkyl carbonate and a product diol, (b) withdrawing a dialkyl carbonate-containing liquid from the reaction mixture, followed by separation of the dialkyl carbonate from the dialkyl carbonate-containing liquid, and (c) withdrawing a diol-containing liquid from the reaction mixture, followed by separation of the diol from the diol-containing liquid, wherein the cyclic carbonate contains a cyclic ether in an amount of from 0.1 to 3,000 ppm by weight, and the product dialkyl carbonate contains a carbonate ether of not more than 10,000 ppm by weight.

Abstract: It is an object of the present invention to provide a specific process that enables dialkyl carbonates and diols to be produced on an industrial scale of not less than 2 ton/hr and not less than 1.3 ton/hr respectively with high selectivity and high productivity stably for a prolonged period of time through a reactive distillation system of taking cyclic carbonates and aliphatic monohydric alcohols as starting materials, continuously feeding the starting materials into a continuous multi-stage distillation column in which a catalyst is present, and carrying out reaction and distillation simultaneously in the column. Although there have been many proposals regarding processes for the production of the dialkyl carbonates and the diols through a reactive distillation method, these have all been on a small scale and short operating time laboratory level, and there have been no disclosures whatsoever on a specific process or apparatus enabling mass production on an industrial scale.

Abstract: A specific industrially useful process for the production of a high-purity diaryl carbonate in which a diaryl carbonate having low contents of intermediate boiling point and high boiling point impurities is produced is disclosed. As a starting material, a reaction mixture containing an alkyl aryl carbonate obtained through a transesterification reaction between a dialkyl carbonate and an aromatic monohydroxy compound is used. The process in which separation by distillation is carried out uses three distillation columns in a specified order. Moreover, it is particularly preferable if a reactive distillation column and the three distillation columns, each of which has a specified structure, and the three distillation columns are each operated under specified distillation conditions.

Abstract: An aromatic polycarbonate that is obtained by transesterification between a high-purity diphenyl carbonate and an aromatic dihydroxy compound. A specific industrially useful process for the production of a high-purity diaryl carbonate in which a diaryl carbonate having low contents of intermediate boiling point and high boiling point impurities is produced is disclosed. As a starting material, a reaction mixture containing an alkyl aryl carbonate obtained through a transesterification reaction between a dialkyl carbonate and an aromatic monohydroxy compound is used. The process in which separation by distillation is carried out uses three distillation columns in a specified order. Moreover, it is particularly preferable if a reactive distillation column and the three distillation columns, each of which has a specified structure, and the three distillation columns are each operated under specified distillation conditions.

Abstract: It is an object of the present invention to provide a specific apparatus and process for industrially producing a high-purity diol by taking a cyclic carbonate and an aliphatic monohydric alcohol as starting materials. Moreover, it is an object to thus provide a specific industrial apparatus and industrial production process that are inexpensive and, for example, enable the high-purity diol to be produced in an amount of not less than 1 ton/hr, preferably not less than 2 tons/hr, more preferably not less than 3 tons/hr, stably for a prolonged period of time (e.g. not less than 1000 hours, preferably not less than 3000 hours, more preferably not less than 5000 hours).

Abstract: It is an object of the present invention to provide a solution by providing a specific process that enables a dialkyl carbonate and a diol to be produced on an industrial scale of not less than 2 ton/hr and not less than 1.3 ton/hr respectively with high selectivity and high productivity stably for a prolonged period of time through a reactive distillation system of taking a cyclic carbonate and an aliphatic monohydric alcohol as starting materials, continuously feeding the starting materials into a continuous multi-stage distillation column in which a catalyst is present, and carrying out reaction and distillation simultaneously in the column. Although there have been many proposals regarding processes for the production of the dialkyl carbonate and the diol through a reactive distillation method, these have all been on a small scale and short operating time laboratory level, and there have been no disclosures whatsoever on a specific process or apparatus enabling mass production on an industrial scale.

Abstract: It is an object of the present invention to provide a specific process that enables a dialkyl carbonate and a diol to be produced on an industrial scale of not less than 2 ton/hr and not less than 1.3 ton/hr respectively with high selectivity and high productivity stably for a prolonged period of time through a reactive distillation system of taking a cyclic carbonate and an aliphatic monohydric alcohol as starting materials, continuously feeding the starting materials into a continuous multi-stage distillation column in which a catalyst is present, and carrying out reaction and distillation simultaneously in the column. Although there have been many proposals regarding processes for the production of the dialkyl carbonate and the diol through the reactive distillation method, these have all been on a small scale and short operating time laboratory level, and there have been no disclosures whatsoever on a specific process or apparatus enabling mass production on an industrial scale.

Abstract: It is an object of the present invention to provide a specific process that enables a high-quality high-performance aromatic polycarbonate having excellent mechanical properties and no discoloration to be produced industrially in a large amount (e.g. not less than 1 ton/hr) stably for a prolonged period of time (e.g. not less than 1000 hours, preferably not less than 3000 hours, more preferably not less than 5000 hours) from a dialkyl carbonate and an aromatic dihydroxy compound.