Abstract: The present application addresses the problem of providing a method for efficiently producing a dialkyl carbonate. The problem can be solved by a method for producing a dialkyl carbonate by reacting urea and at least one alkyl carbamate with an aliphatic alcohol in the presence of a catalyst, the method including introducing a gas for expelling ammonia generated by the reaction into a reactor in which the reaction is being conducted and discharging the ammonia generated in the reactor and the introduced gas, the reaction being conducted so that the gas introduction satisfies relationship (1). 52.0<((A+B)×22400+L×M/17.03×22400)/L<91.0??(1) (In formula (1), A, B, L, and M are as defined above.

Abstract: A method for producing an asymmetric chain carbonate by reacting an alcohol with a halocarbonate ester compound in the presence of a basic magnesium salt.

Abstract: A method for producing an asymmetric chain carbonate by reacting an alcohol with a halocarbonate ester compound in the presence of a basic magnesium salt.

Abstract: A method for preparing dialkyl carbonate is provided. The preparation method includes the following steps. An alcohol compound, carbon dioxide and a catalyst are mixed to form a mixing solution. Organic acid is added to the mixing solution to carry out a synthesis reaction of dialkyl carbonate. The alcohol compound includes methanol, ethanol, propanol or butanol. The catalyst includes cerium oxide, zirconium oxide, titanium oxide, lanthanum oxide or a combination thereof. The organic acid includes formic acid, acetic acid, propionic acid, butyric acid, valeric acid or a combination thereof.

Abstract: Provided is a method for regenerating an aromatic amide compound into a corresponding aromatic nitrile compound, the method realizing a dehydration reaction of providing a target compound selectively at a high yield with generation of a by-product being suppressed. Also provided is a method for producing an aromatic nitrile compound that decreases the number of steps of dehydration reaction and significantly improves the reaction speed at a pressure close to normal pressure. Furthermore, the above-described production method is applied to a carbonate ester production method to provide a method for producing carbonate ester efficiently. The above-described objects are achieved by a method for producing an aromatic nitrile compound including a dehydration reaction of dehydrating an aromatic amide compound, in which the dehydration reaction uses diphenylether.

Abstract: The present invention discloses an improved catalyst free process for synthesis of alkyl carbamates in an integrated system comprising a tubular reactor and a striper. The process comprises reacting urea and an alcohol in said tubular reactor under autogeneous pressure; wherein said process provides >90% selectivity towards alkyl carbamate. The mixture of urea and alcohol is N fed to the tubular reactor at a particular feed rate. The tubular reactor is heated externally under autogeneous pressure to carry out a synthesis reaction producing alkyl carbamate and ammonia. The ammonia is removed from the tubular reactor by the striper. The tubular reactor and the stripper are arranged in series to reduce the equilibrium limitations of the reaction and drive the reaction in forward direction.

Abstract: In one embodiment, a formed catalyst can comprise: a Ge-ZSM-5 zeolite; a binder comprising silica with 1 to less than 5 wt % non-silica oxides; less than or equal to 0.1 wt % residual carbon; 0.4 to 1.5 wt % platinum; and 4.0 to 4.8 wt % Cs; wherein the weight percentages are based upon a total weight of the catalyst. In one embodiment, a method of making a formed catalyst can comprise: mixing an uncalcined Ge-ZSM-5 zeolite and a binder to form a mixture; forming the mixture into a formed zeolite; calcining the formed zeolite to result in the formed zeolite having less than or equal to 0.1 wt % of residual carbon; ion-exchanging the formed zeolite with cesium; depositing platinum on the formed zeolite; and heating the formed zeolite to result in a final catalyst; wherein the final catalyst comprises 4.0 to 4.8 wt % cesium and 0.4 to 1.5 wt % platinum.

Abstract: 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.

Abstract: The present invention relates to a continuous process for producing lower dialkyl carbonates as a main product and alkylene glycol as a by-product by transesterification of a cyclic alkylene carbonate (e.g. ethylene or propylene carbonate) with lower alkyl alcohols in the presence of a catalyst and also the necessary purification of the dialkyl carbonate in a subsequent process step. For optimization of the economic efficiency and energy efficiency of the process, additional devices are used for intermediate heating of the internal liquid streams within the apparatus.

Abstract: This invention relates to a supported quaternary phosphonium catalyst, preparation thereof and use thereof in producing dialkyl carbonates. The supported quaternary phosphonium catalyst of this invention has the following average molecular structure (I), and is characterized by a relatively high and stable catalyst activity. wherein, each of X, L, n, R1, R2, R3 and is the same as that in the specification.

Abstract: An asymmetric chain carbonate can be produced in a single-step reaction comprising a step of reacting methyl nitrite, carbon monoxide, and 0.05-1.5 moles of an aliphatic alcohol having 2-6 carbon atoms or an alicyclic alcohol having 5-6 carbon atoms per one mole of methyl nitrile in a gaseous phase in the presence of a solid catalyst comprising a platinum group metal or a compound thereof placed on a support.

Abstract: Disclosed is a method for preparing, by transcarbonation, a compound of formula (I), including reacting a polyol of formula (II) with an alkyl carbonate or an alkylene carbonate in the presence of a catalytic system consisting of a catalytic entity selected from among the rare earth oxides or the mixtures thereof, and optionally an inert substrate.

Abstract: An eco-friendly process for making dimethyl carbonate comprising contacting methanol with carbon dioxide in the presence of a solid, calcined catalyst derived from zirconium phosphonate catalyst having molecular formula: Zr(X)2-nYn.mH2O where X refers to phosphonate, Y refers to HPO42? or HPO32?, n varies from 0.2 to 1.8 and m varies from 0 to 5, is disclosed.

Abstract: The present disclosure is directed to, in part, an aliphatic polycarbonate polymerization reaction initiated by combining an epoxide with carbon dioxide in the presence of a catalytic transition metal-ligand complex to form a reaction mixture, and further quenching that polymerization reaction by contacting the reaction mixture with an acid containing a non-nucleophilic anion produces a crude polymer solution with improved stability and processability.

Abstract: A process for producing a high-purity dimethyl carbonate, which includes: (I) cooling a commercial grade dimethyl carbonate containing 1 ppm or more of chlorine to a temperature from +6° C. to ?5° C. at a rate from 0.5-2° C./hour, to obtain a first solid dimethyl carbonate; (II) heating the first solid dimethyl carbonate to a temperature from ?5° C. to +6° C. at a rate of 1-5° C./hour, to obtain a mixture comprising a second solid dimethyl carbonate and a predetermined amount of a first liquid dimethyl carbonate; (III) separating the first liquid dimethyl carbonate from the mixture, to obtain the second solid dimethyl carbonate; (IV) heating the second solid dimethyl carbonate to a temperature from 20° C. to 40° C., to obtain a second liquid dimethyl carbonate, wherein the second liquid dimethyl carbonate has a purity degree higher than 99.99% and a chlorine content lower than or equal to 1 ppm.

Abstract: The invention relates to a process for the preparation of an alkanediol and a dialkyl carbonate comprising: reacting an alkylene carbonate and an alkanol in the presence of a transesterification catalyst to obtain a reaction mixture comprising dialkyl carbonate, unconverted alkanol, alkanediol, unconverted alkylene carbonate and an alkoxy alkanol impurity; and subjecting the reaction mixture to distillation in a series of steps.

Abstract: Process for the production of a chemical compound from a carbon dioxide starting material, comprising the steps of a) providing a feed stream consisting mainly of carbon dioxide; b) electrolysing in an electrolysis stage the carbon dioxide in the feed stream to a first gas stream containing carbon monoxide and a second gas stream containing oxygen, wherein the molar ratio between carbon monoxide and oxygen is about 1:0.5 in an electrolysis stage; c) adjusting the composition of the first gas stream or the second gas stream or both gas streams to include carbon dioxide, either by operating at less than full conversion of CO2 or by sweeping one or both gas streams with a gas containing CO2 or by at some stage between the electrolysis cell and the oxidative carbonylation reactor diluting one or both gas streams with a gas containing CO2; all while maintaining an overall molar ratio of carbon monoxide to oxygen of about 1:0.

Abstract: The present invention relates to novel compounds and their use as fragrance materials.

Abstract: The invention provides a method for producing organic carbonates via the reaction of alcohols and carbon monoxide with oxygen adsorbed on a metallic gold or gold alloy catalyst.

Abstract: The present disclosure provides novel glucagon-like peptide-1 (GLP-1) receptor modulators such as compounds of Formula (I) or (II), and pharmaceutically acceptable salts thereof. The present disclosure also provides pharmaceutical compositions, kits, and uses that involve the GLP-1 receptor modulators for regulating blood glucose levels and/or treating diabetes via, e.g., modulating the endogenous signaling pathways mediated by the GLP-1 receptor.

Abstract: Fluoroalkyl alkyl carbonates which are suitable as additives or solvents in lithium ion batteries are prepared from fluoroalkyl fluoroformiates and an aldehyde, preferably formaldehyde and acetaldehyde. 1,1?-difluoromethyl carbonate and 1,1?-di-fluorodiethylcarbonate are the preferred compounds prepared by the process of the present invention.

Abstract: Dialkyl carbonate and diol products are prepared in an integrated process performed by reacting an alkylene oxide with carbon dioxide in the presence of a non-halide-containing homogeneous carbonation catalyst in a first reaction zone to form a crude cyclic carbonate product. The crude cyclic carbonate product is introduced along with an aliphatic monohydric alcohol to a second reaction zone containing a transesterification catalyst. The transesterification catalyst is comprised of a strongly basic Type I ion exchange resin in gel having a particular form. The cyclic carbonate product and monohydric alcohol are reacted to form the dialkyl carbonate and diol products. In another aspect, dialkyl carbonate and diol products are prepared in an integrated process wherein a halide-containing homogeneous carbonation catalyst is used to form a crude cyclic carbonate product that is then used in a transesterification reaction.

Abstract: The invention provides a method for producing organic carbonates via the reaction of alcohols and carbon monoxide with oxygen adsorbed on a metallic gold or gold alloy catalyst.

Abstract: The present disclosure is a system and method for producing a first product from a first region of an electrochemical cell having a cathode and a second product from a second region of the electrochemical cell having an anode. The method may include a step of contacting the first region with a catholyte including carbon dioxide and contacting the second region with an anolyte including a recycled reactant. The method may further include applying an electrical potential between the anode and the cathode sufficient to produce carbon monoxide recoverable from the first region and a halogen recoverable from the second region.

Abstract: The disclosure provides a method for alcoholysis of a polycarbonate-containing composition comprising a polycarbonate and a component comprising a phosphorus-containing flame retardant, an acrylonitrile-butadiene-styrene, or a combination of the phosphorus-containing flame retardant and acrylonitrile-butadiene-styrene. The method comprises contacting the composition with a solvent that forms a solution or a filterable suspension of the component but not the polycarbonate; separating the solution or the filterable suspension from the polycarbonate; and heating the polycarbonate in the presence of an alcohol and a catalyst at a temperature from 70° C. to 200° C., and a pressure from 5 mbar to 40 bar for a time sufficient to depolymerize the polycarbonate and produce a dihydroxy aromatic compound and a dialkyl carbonate.

Abstract: A method of forming a cyclic carbonate product is carried out by reacting an alkylene oxide, such as ethylene oxide, with carbon dioxide in the presence of a metal organic framework (MOF) catalyst with less than 0.5 mol % of any potassium or quaternary ammonium salts present based on moles of alkylene oxide feed in a reaction zone under reaction conditions to form a cyclic carbonate product. The cyclic carbonate product may be optionally fed as a crude carbonate product that does not undergo any purification or separation, other than the optional removal of any portion of unreacted alkylene oxide, carbon dioxide, and light hydrocarbon gases, to a second reaction zone containing a transesterification catalyst along with an aliphatic monohydric alcohol. The cyclic carbonate product and monohydric alcohol are allowed to react under reaction conditions to form the dialkyl carbonate and diol products.

Abstract: The present invention provides a method for preparing dialkyl carbonate from urea or alkyl carbamate and alkyl alcohol using an ionic liquid comprising a cation, which produces a hydrogen ion, and a hydrophobic anion containing fluorine with high temperature stability in the presence of catalyst containing a metal oxide or hydrotalcite. Since the present invention can prepare dialkyl carbonate at a pressure lower than those of existing methods, it does not require an expensive pressure control device and peripheral devices for maintaining high pressure including the installation cost. It is also the method for preparing a dialkyl carbonate with high yield, thus improving economical efficiency. Moreover, the method of the present invention hardly produces any waste during the process and is thus an eco-friendly method.

Abstract: Embodiments of the present invention relate to carbon dioxide sequestration systems and methods. In an embodiment, the invention includes a method of sequestering carbon dioxide. The method can include mixing carbon dioxide with an alcohol to form a reaction mixture and contacting the reaction mixture with a metal oxide catalyst under reaction conditions sufficient to produce a carbonate as a reaction product. In an embodiment, the invention includes a carbon dioxide sequestration system. The system can include a carbon dioxide supply source, an alcohol supply source, and a reaction vessel. A metal oxide catalyst can be disposed within the reaction vessel. The system can be configured to mix carbon dioxide from the carbon dioxide supply source with an alcohol from the alcohol supply source to form a reaction mixture and contact the reaction mixture with the metal oxide catalyst. Other embodiments are also described herein.

Abstract: Disclosed is a method for preparing a dialkyl carbonate, in which a dialkyl carbonate such as dimethyl carbonate is economically prepared in an environmentally-friendly manner at a higher yield while reducing generation of a by-product. The method for preparing the dialkyl carbonate includes reacting urea, an alkyl carbamate having 1 to 3 carbon atoms, or a mixture thereof with a monovalent alcohol having 1 to 3 carbon atoms in the presence of a room temperature ionic liquid and a catalyst including a salt of a transition metal or a rare earth metal.

Abstract: A cooling sensation agent composition with a prolonged cool sensation effect is provided comprising at least one compound selected from the group consisting of aceia or ketal derivatives of 3-(1-menthoxy)propan-1,2-diol represented by Formula (1), single or mixed carbonic esters ol one or two kinds ol alcohols represented by Formula (2), and carboxylic esters represented by Formula (4). A sensory stimulation agoni composition, a flavor or fragrance composition, a beverage or food product, a perfume or cosmetic product, a toiletry product, a daily utensil product or grocery, a fiber, a fiber product, a cloth or a medicine comprising the cooling sensation agent composition; a production method thereof; a cooling processing method of a fiber, fiber product or a cloth, comprising compounding the cooling sensation agent; and new compounds are also provided.

Abstract: The present invention provides a method for preparing dialkyl carbonate from urea or alkyl carbamate and alkyl alcohol using an ionic liquid comprising a cation, which produces a hydrogen ion, and a hydrophobic anion containing fluorine with high temperature stability in the presence of catalyst containing a metal oxide or hydrotalcite. Since the present invention can prepare dialkyl carbonate at a pressure lower than those of existing methods, it does not require an expensive pressure control device and peripheral devices for maintaining high pressure including the installation cost. It is also the method for preparing a dialkyl carbonate with high yield, thus improving economical efficiency. Moreover, the method of the present invention hardly produces any waste during the process and is thus an eco-friendly method.

Abstract: The invention relates to a process for the preparation of an alkanediol and a dialkyl carbonate comprising: reacting an alkylene carbonate and an alkanol in the presence of a transesterification catalyst to obtain a reaction mixture comprising dialkyl carbonate, unconverted alkanol, alkanediol and unconverted alkylene carbonate; and then subjecting the mixture to separation in three distillation columns.

Abstract: This invention relates to a supported quaternary phosphonium catalyst, preparation thereof and use thereof in producing dialkyl carbonates. The supported quaternary phosphonium catalyst of this invention has the following average molecular structure (I), and is characterized by a relatively high and stable catalyst activity. wherein, each of X, L, n, R1, R2, R3 and is the same as that in the specification.

Abstract: A method for producing acetic anhydride that includes operating a high shear device at a shear rate of greater than about 20,000 s?1, wherein the high shear device is configured with a rotor and a stator; forming in the high shear device an emulsion having a liquid catalyst dispersed in an acetic acid solution; introducing the emulsion into a reactor at conditions suitable for the production of ketene; and reacting at least some ketene with acetic acid to produce acetic anhydride.

Abstract: A method of preparing aromatic carbonate from dialkyl carbonate includes reacting an aromatic hydroxyl compound and dialkyl carbonate in the presence of at least one type of samarium-containing catalyst represented by Formula 1, Formula 2, or a combination thereof: SmX3??[Formula 1] wherein each X is the same or different and is independently C1 to C10 alkoxy, C1 to C10 alkyl phenoxy or phenoxy, and wherein R1 and R2 are the same or different and are independently hydrogen or C1 to C6 alkyl.

Abstract: The present invention provides a reactor system comprising: —one or more purification zones comprising an absorbent which comprises silver, an alkali or alkaline earth metal, and a support material having a surface area of more than 20 m2/g, and —a reaction zone comprising a catalyst, which reaction zone is positioned downstream from the one or more purification zones; an absorbent; a process for reacting a feed comprising one or more feed components; and a process for preparing a 1,2-diol, a 1,2-diol ether, a 1,2-carbonate, or an alkanolamine.

Abstract: The present invention provides a salt represented by the formula (I): wherein Q1 and Q2 independently each represent a fluorine atom or a C1-C6 perfluoroalkyl group, L1 represents a C1-C17 divalent saturated hydrocarbon group in which one or more —CH2— can be replaced by —O— or —CO—, L2 represents a single bond or a C1-C6 alkanediyl group in which one or more —CH2— can be replaced by —O— or —CO—, Y represents a C3-C18 alicyclic hydrocarbon group which can have one or more substituents, and one or more —CH2— in the alicyclic hydrocarbon group can be replaced by —O—, —CO— or —SO2—, and Z+ represents an organic counter ion.

Abstract: Dialkyl carbonate and diol products are prepared in an integrated process performed by reacting an alkylene oxide with carbon dioxide in the presence of a non-halide-containing homogeneous carbonation catalyst in a first reaction zone to form a crude cyclic carbonate product. The crude cyclic carbonate product is introduced along with an aliphatic monohydric alcohol to a second reaction zone containing a transesterification catalyst. The transesterification catalyst is comprised of a strongly basic Type I ion exchange resin in gel having a particular form. The cyclic carbonate product and monohydric alcohol are reacted to form the dialkyl carbonate and diol products. In another aspect, dialkyl carbonate and diol products are prepared in an integrated process wherein a halide-containing homogeneous carbonation catalyst is used to form a crude cyclic carbonate product that is then used in a transesterification reaction.

Abstract: The present invention relates to a continuous process for preparing lower dialkyl carbonates as main product and alkylene glycol as by-product by transesterification of a cyclic alkylene carbonate (e.g. ethylene carbonate or propylene carbonate) with lower alkyl alcohols in the presence of a catalyst and also the required purification of the dialkyl carbonate in a subsequent process step. To optimize the economics and energy efficiency of the process, additional devices are used for intermediate heating of the liquid streams in the apparatus.

Abstract: Dialkyl carbonate and diol products are prepared in an integrated process performed by reacting an alkylene oxide with carbon dioxide in the presence of a non-halide-containing homogeneous carbonation catalyst in a first reaction zone to form a crude cyclic carbonate product. The crude cyclic carbonate product is introduced along with an aliphatic monohydric alcohol to a second reaction zone containing a transesterification catalyst. The transesterification catalyst is comprised of a strongly basic Type I ion exchange resin in gel having a particular form. The cyclic carbonate product and monohydric alcohol are reacted to form the dialkyl carbonate and diol products. In another aspect, dialkyl carbonate and diol products are prepared in an integrated process wherein a halide-containing homogeneous carbonation catalyst is used to form a crude cyclic carbonate product that is then used in a transesterification reaction.

Abstract: A method of forming a cyclic carbonate product is carried out by reacting an alkylene oxide, such as ethylene oxide, with carbon dioxide in the presence of a metal organic framework (MOF) catalyst with less than 0.5 mol % of any potassium or quaternary ammonium salts present based on moles of alkylene oxide feed in a reaction zone under reaction conditions to form a cyclic carbonate product. The cyclic carbonate product may be optionally fed as a crude carbonate product that does not undergo any purification or separation, other than the optional removal of any portion of unreacted alkylene oxide, carbon dioxide, and light hydrocarbon gases, to a second reaction zone containing a transesterification catalyst along with an aliphatic monohydric alcohol. The cyclic carbonate product and monohydric alcohol are allowed to react under reaction conditions to form the dialkyl carbonate and diol products.

Abstract: A method of producing a carbonate product including mixing a DMC and methanol mixture with an alcohol, reacting the DMC with the alcohol to form carbonate product, and removing a substantial portion of unreacted DMC and methanol. In one embodiment, the method may be repeated to reach a desired alcohol conversion by adding more DMC and methanol mixture.

Abstract: The invention relates to a process for obtaining a dialkyl carbonate and an alkylene glycol from a stream comprising dialkyl carbonate, alkylene carbonate, alkylene glycol and alcohol, comprising the following steps: (a) distillatively removing a stream (5) comprising dialkyl carbonate and alkylene glycol as a heteroazeotrope from the stream comprising dialkyl carbonate, alkylene carbonate, alkylene glycol and alcohol in a first distillation stage (1), (b) separating the stream (5) comprising dialkyl carbonate and alkylene glycol as a heteroazeotrope into a first crude product stream (27) comprising essentially di-alkyl carbonate and a second crude product stream (29) comprising essentially alkylene glycol in an apparatus for phase separation (25).

Abstract: The present invention relates to a catalyst for the synthesis of organic carbonates, the preparation of the catalyst and the application of this catalyst in the synthesis of organic carbonates from reacting urea and hydroxyl group containing compounds. The catalyst provided in this invention is a calcinate of hydrous salt containing rare earth element at a moderate calcining temperature.

Abstract: Processes for the alcoholysis, inclusive of transesterification and/or disproportionation, of reactants are disclosed. The alcoholysis process may include feeding reactants and a trace amount of soluble organometallic compound to a reactor comprising a solid alcoholysis catalyst, wherein the soluble organometallic compound and the solid alcoholysis catalyst each independently comprise a Group II to Group VI element, which may be the same element in various embodiments. As an example, diphenyl carbonate may be continuously produced by performing transesterification over a solid catalyst followed by disproportionation, where a trace amount of soluble organometallic compound is fed to the transesterification reactor.

Abstract: The invention relates to a process for the preparation of an alkanediol and a dialkyl carbonate comprising: (a) reacting an alkylene carbonate and an alkanol in the presence of a transesterification catalyst to obtain a reaction mixture comprising dialkyl carbonate, unconverted alkanol, alkanediol, unconverted alkylene carbonate and an alkoxy alkanol impurity; (b) subjecting the reaction mixture to distillation in a first distillation column to obtain a top stream comprising dialkyl carbonate, alkanol and alkoxy alkanol impurity and a bottom stream comprising alkanediol and alkylene carbonate; (c) subjecting the bottom stream from the first distillation column to distillation in a second distillation column to obtain a top stream comprising alkanediol and a bottom stream comprising alkylene carbonate; (d) subjecting the lop stream from the first distillation column to distillation in a third distillation column in the presence of a catalyst to effect reaction of the alkoxy alkanol impurity with the dialkyl ca

Abstract: The present invention relates to a continuous process for preparing lower dialkyl carbonates as main product and alkylene glycol as by-product by catalyzed transesterification of a cyclic alkylene carbonate (e.g. ethylene carbonate or propylene carbonate) with lower alcohols, where the reaction of the alkylene carbonate is carried out with an alcohol containing dialkyl carbonate in countercurrent, characterized in that introduction of a stream containing at least 99.5% by weight of alcohol takes place below the point of introduction for the alcohol containing dialkyl carbonate in a particular spacing ratio between the abovementioned points of introduction.

Abstract: The invention relates to a process for preparing polyether carbonate polyols by addition of alkylene oxides and carbon dioxide onto H-functional starter substances using DMC catalysts, wherein one or more starter substances are initially placed in the reactor and one or more starter substances are metered continuously into the reactor during the reaction.

Abstract: A polycarbonate diol which is useful as a raw material compound for producing a polycarbonate-based polyurethane having a sufficient mechanical strength and excellent in a balance of physical properties such as oil resistance, hydrolysis resistance, and weather resistance and which is amorphous. The polycarbonate diol includes repeating units of the below-shown formula (A) and the below-shown formula (B), wherein both terminal groups are hydroxyl groups, the ratio of the below-shown formula (A) to the below-shown formula (B) is 99:1 to 1:99 by mol, and number-average molecular weight is 300 to 10,000.

Abstract: A process for producing a high-purity dimethyl carbonate, which includes: (I) cooling a commercial grade dimethyl carbonate containing 1 ppm or more of chlorine to a temperature from +6° C. to ?5° C. at a rate from 0.5-2° C./hour, to obtain a first solid dimethyl carbonate; (II) heating the first solid dimethyl carbonate to a temperature from ?5° C. to +6° C. at a rate of 1-5° C./hour, to obtain a mixture comprising a second solid dimethyl carbonate and a predetermined amount of a first liquid dimethyl carbonate; (III) separating the first liquid dimethyl carbonate from the mixture, to obtain the second solid dimethyl carbonate; (IV) heating the second solid dimethyl carbonate to a temperature from 20° C. to 40° C., to obtain a second liquid dimethyl carbonate, wherein the second liquid dimethyl carbonate has a purity degree higher than 99.99% and a chlorine content lower than or equal to 1 ppm.