Abstract: A method of recovering ammonia by the distillation of an aqueous solution containing ammonia, carbon dioxide and hydrogen cyanide. The distillation is conducted using a distillation apparatus having at least its portion which comes into contact with the aqueous solution made of an alloy 1 or alloy 2. The alloy 1 contains 3% by weight or more of molybdenum, 15% by weight or more of nickel and 15% by weight or more of chromium. The alloy 2 contains 1% by weight or more of molybdenum, 9% by weight or less of nickel and 20% by weight or more of chromium. The use of the alloy 1 or alloy 2 prevents the corrosion of the distillation apparatus and enables the stable recovery of ammonia for a long period of time.

Abstract: A method of producing a primary amine by the hydrogenation of a nitrile in the presence of a hydrogenation catalyst. The hydrogenation catalyst contains at least one metal selected from the group consisting of nickel, cobalt and iron. Before use in the hydrogenation of nitrile, the hydrogenation catalyst is pretreated with at least one treating agent selected from the group consisting of hydrocarbons, alcohols, ethers, esters and carbon monoxide at 150 to 500° C.

Abstract: A solid xylylenediamine solidified in a container is extremely excellent in storage stability as compared with a liquid xylylenediamine, and is less degraded by discoloration even when stored in an atmosphere containing oxygen. By charging a liquid xylylenediamine into a container, solidifying the liquid xylylenediamine into a solid xylylenediamine in the container under cooling without delay after the charging, and storing the solid xylylenediamine in the container while maintaining the xylylenediamine in a solid state, the xylylenediamine is stored for a long period of time without causing deterioration of quality such as discoloration.

Abstract: In the process of the present invention, xylylenediamine and/or cyanobenzylamine is produced by a catalytic liquid-phase hydrogenation of a phthalonitrile compound. The liquid-phase hydrogenation is performed by controlling the concentration of a benzamide compound to a specific level or lower. In a preferred embodiment, the concentration of a benzoic acid compound is further controlled to a specific level or lower. By the process, xylylenediamine and/or cyanobenzylamine is produced at high yields and the catalyst life is prolonged.

Abstract: A crude liquid containing 1,3-bis(aminomethyl)cyclohexane and a high-boiling component having a boiling point higher than that of 1,3-bis(aminomethyl)cyclohexane is distilled. By controlling the distillation conditions, the high-boiling component is prevented from entering into a distilled 1,3-bis(aminomethyl)cyclohexane and the content of a low-boiling component in the distilled 1,3-bis(aminomethyl)cyclohexane is minimized.

Abstract: A crude liquid containing 1,3-bis(aminomethyl)cyclohexane and a high-boiling component having a boiling point higher than that of 1,3-bis(aminomethyl)cyclohexane is distilled. By controlling the distillation conditions, the high-boiling component is prevented from entering into a distilled 1,3-bis(aminomethyl)cyclohexane and the content of a low-boiling component in the distilled 1,3-bis(aminomethyl)cyclohexane is minimized.

Abstract: In the process of the present invention for producing a xylylenediamine by a liquid-phase hydrogenation of a dicyanobenzene in the presence of a catalyst, the catalyst having its activity decreased during the course of use in the hydrogenation is reactivated and a pressure drop through a fixed bed catalyst layer is got rid of, thereby regenerating the catalyst for reuse in the subsequent hydrogenation of the dicyanobenzene to produce the xylylenediamine. The catalyst is regenerated by brought into contact with a hydrogen-containing gas under controlled temperature conditions.

Abstract: A solid xylylenediamine solidified in a container is extremely excellent in storage stability as compared with a liquid xylylenediamine, and is less degraded by discoloration even when stored in an atmosphere containing oxygen. By charging a liquid xylylenediamine into a container, solidifying the liquid xylylenediamine into a solid xylylenediamine in the container under cooling without delay after the charging, and storing the solid xylylenediamine in the container while maintaining the xylylenediamine in a solid state, the xylylenediamine is stored for a long period of time without causing deterioration of quality such as discoloration.

Abstract: In the method of the present invention, xylylenediamine is produced by a two-stage hydrogenation of a dicyanobenzene compound. In a first stage (a), the hydrogenation is performed until a conversion of nitrile groups reaches 90 mol % or higher and less than 99.9 mol %. In a second stage (b), the hydrogenation is further continued at temperatures 10° C. or more higher than in the step (a) until the conversion of nitrile groups reaches a level which is higher than that attained in the step (a) and equal to 99.5 mol % or more. In the present invention, a highly pure xylylenediamine containing a minimized amount of cyanobenzylamine is efficiently produced in a simple manner without needing a specific purification, and also without deteriorating the use efficiency of the catalyst while reducing the amount of the dicyanobenzene compound remaining not reacted and the generation of the intermediate cyanobenzylamine.

Abstract: In the method of the present invention, xylylenediamine is produced by a two-stage hydrogenation of a dicyanobenzene compound. In a first stage (a), the hydrogenation is performed until a conversion of nitrile groups reaches 90 mol % or higher and less than 99.9 mol %. In a second stage (b), the hydrogenation is further continued at temperatures 10° C. or more higher than in the step (a) until the conversion of nitrile groups reaches a level which is higher than that attained in the step (a) and equal to 99.5 mol % or more. In the present invention, a highly pure xylylenediamine containing a minimized amount of cyanobenzylamine is efficiently produced in a simple manner without needing a specific purification, and also without deteriorating the use efficiency of the catalyst while reducing the amount of the dicyanobenzene compound remaining not reacted and the generation of the intermediate cyanobenzylamine.

Abstract: In the process of the present invention for producing a xylylenediamine by a liquid-phase hydrogenation of a dicyanobenzene in the presence of a catalyst, the catalyst having its activity decreased during the course of use in the hydrogenation is reactivated and a pressure drop through a fixed bed catalyst layer is got rid of, thereby regenerating the catalyst for reuse in the subsequent hydrogenation of the dicyanobenzene to produce the xylylenediamine. The catalyst is regenerated by brought into contact with a hydrogen-containing gas under controlled temperature conditions.

Abstract: In the process of the present invention, xylylenediamine and/or cyanobenzylamine is produced by a catalytic liquid-phase hydrogenation of a phthalonitrile compound. The liquid-phase hydrogenation is performed by controlling the concentration of a benzamide compound to a specific level or lower. In a preferred embodiment, the concentration of a benzoic acid compound is further controlled to a specific level or lower. By the process, xylylenediamine and/or cyanobenzylamine is produced at high yields and the catalyst life is prolonged.

Abstract: In a method for producing xylylenediamine by hydrogenating phthalonitrile separated from a gas produced by causing xylene to react with ammonia and oxygen-containing gas in the presence of a catalyst, (1) the gas is brought into contact with an organic solvent to trap phthalonitrile; (2) a liquid in which phthalonitrile is trapped is distilled, to thereby recover phthalonitrile and the organic solvent from the top of the column and separate at the bottom of the column impurities having boiling points higher than that of phthalonitrile; (3) the organic solvent is recovered from the top of the column and liquefied phthalonitrile of high purity is recovered at the bottom of the column; and (4) the phthalonitrile is hydrogenated after mixing with liquid ammonia and at least one solvent selected from aromatic hydrocarbon and saturated hydrocarbon. Thus, high-purity phthalonitrile is produced at high yield industrially efficiently.

Abstract: In a method for separating isophthalonitrile from a gas produced by causing m-xylene to react with ammonia and oxygen-containing gas in the presence of a catalyst, the gas is brought into contact with an organic solvent having a boiling point lower than that of isophthalonitrile; a liquid in which isophthalonitrile is trapped in a trapping step is distilled, to thereby recover isophthalonitrile and the organic solvent from the top of the column and separate at the bottom of the column impurities having boiling points higher than that of isophthalonitrile; and the organic solvent is recovered from the top of the rectification column and liquefied isophthalonitrile of high purity is recovered at the bottom of the column.

Abstract: In a method for producing xylylenediamine by hydrogenating phthalonitrile separated from a gas produced by causing xylene to react with ammonia and oxygen-containing gas in the presence of a catalyst, (1) the gas is brought into contact with an organic solvent to trap phthalonitrile; (2) a liquid in which phthalonitrile is trapped is distilled, to thereby recover phthalonitrile and the organic solvent from the top of the column and separate at the bottom of the column impurities having boiling points higher than that of phthalonitrile; (3) the organic solvent is recovered from the top of the column and liquefied phthalonitrile of high purity is recovered at the bottom of the column; and (4) the phthalonitrile is hydrogenatd after mixing with liquid ammonia and at least one solvent selected from aromatic hydrocarbon and saturated hydrocarbon. Thus, high-purity phthalonitrile is produced at high yield industrially efficiently.

Abstract: A method for producing xylylenediamine by hydrogenating phthalonitrile synthesized through ammoxidation of xylene, wherein phthalonitrile is trapped in an organic solvent (A) by bringing a gas produced through ammoxidation into direct contact with the organic solvent (A), and hydrogenation including adding liquid ammonia to the resultant mixture is carried out without separation of phthalonitrile trapped in the organic solvent (A). Through this method, the phthalonitrile can be readily recovered from the produced gas and at high yield without need for new equipment, and xylylenediamine can be efficiently produced through hydrogenation. Xylylenediamine of high purity can be obtained by subjecting the produced xylylenediamine to extraction by use of an organic solvent (B) and water.

Abstract: A method for producing xylylenediamine by hydrogenating phthalonitrile synthesized through ammoxidation of xylene, wherein phthalonitrile is trapped in an organic solvent (A) by bringing a gas produced through ammoxidation into direct contact with the organic solvent (A), and hydrogenation including adding liquid ammonia to the resultant mixture is carried out without separation of phthalonitrile trapped in the organic solvent (A). Through this method, the phthalonitrile can be readily recovered from the produced gas and at high yield without need for new equipment, and xylylenediamine can be efficiently produced through hydrogenation. Xylylenediamine of high purity can be obtained by subjecting the produced xylylenediamine to extraction by use of an organic solvent (B) and water.

Abstract: In a method for separating isophthalonitrile from a gas produced by causing m-xylene to react with ammonia and oxygen-containing gas in the presence of a catalyst, the gas is brought into contact with an organic solvent having a boiling point lower than that of isophthalonitrile; a liquid in which isophthalonitrile is trapped in a trapping step is distilled, to thereby recover isophthalonitrile and the organic solvent from the top of the column and separate at the bottom of the column impurities having boiling points higher than that of isophthalonitrile; and the organic solvent is recovered from the top of the rectification column and liquefied isophthalonitrile of high purity is recovered at the bottom of the column.