Abstract: Provided is a method for manufacturing a catalyst with which it is possible to obtain a supported metal ammonia synthesis catalyst, in which there are restrictions in terms of producing method and producing facility, and particularly large restrictions for industrial-scale producing, in a more simple manner and so that the obtained catalyst has a high activity. This method for manufacturing an ammonia synthesis catalyst includes: a first step for preparing 12CaO·7Al2O3 having a specific surface area of 5 m2/g or above; a second step for supporting a ruthenium compound on the 12CaO·7Al2O3; and a third step for performing a reduction process on the 12CaO·7Al2O3 supporting the ruthenium compound, obtained in the second step. This invention is characterized in that the reduction process is performed until the average particle diameter of the ruthenium after the reduction process has increased by at least 15% in relation to the average particle diameter of the ruthenium before the reduction process.

Abstract: A molded sintered body containing a mayenite type compound, an inorganic binder sintered material, and a transition metal, wherein a content of the inorganic binder sintered material is 3 to 30 parts by mass with respect to 100 parts by mass of the molded sintered body, and the molded sintered body has at least one pore peak in each of a pore diameter range of 2.5 to 20 nm and a pore diameter range of 20 to 350 nm. A method for producing the molded sintered body, including mixing a precursor of a mayenite type compound and a raw material of an inorganic binder sintered material to prepare a mixture; molding the mixture to prepare a molded body of the mixture; firing the molded body to prepare a fired product; and supporting a transition metal on the fired product to produce a molded sintered body.

Abstract: Provided is a method for manufacturing a catalyst with which it is possible to obtain a supported metal ammonia synthesis catalyst, in which there are restrictions in terms of producing method and producing facility, and particularly large restrictions for industrial-scale producing, in a more simple manner and so that the obtained catalyst has a high activity. This method for manufacturing an ammonia synthesis catalyst includes: a first step for preparing 12CaO.7Al2O3 having a specific surface area of 5 m2/g or above; a second step for supporting a ruthenium compound on the 12CaO.7Al2O3; and a third step for performing a reduction process on the 12CaO.7Al2O3 supporting the ruthenium compound, obtained in the second step. This invention is characterized in that the reduction process is performed until the average particle diameter of the ruthenium after the reduction process has increased by at least 15% in relation to the average particle diameter of the ruthenium before the reduction process.

Abstract: The ammonia synthesis system of the present invention includes an ammonia synthesis reaction unit (10) that synthesizes ammonia from nitrogen and hydrogen; an ammonia cooler (20) that cools an ammonia-containing gas discharged from the ammonia synthesis reaction unit (10); a gas-liquid separator (30) that separates ammonia liquefied by the ammonia cooler (20) from a circulated gas; and an ammonia synthesizing gas supplying unit (40) that supplies nitrogen gas and hydrogen gas, the circulated gas being supplied to the ammonia synthesis reaction unit, the circulated gas supplied to the ammonia synthesis unit having an ammonia gas concentration of 3% by volume or more. The method for producing ammonia of the present invention includes reacting nitrogen and hydrogen using a circulated gas having an ammonia gas concentration of 3% by volume or more and using an ammonia synthesis catalyst under a condition of a reaction pressure of 10 MPa or less to produce ammonia.

Abstract: Provided is a method for manufacturing a catalyst with which it is possible to obtain a supported metal ammonia synthesis catalyst, in which there are restrictions in terms of producing method and producing facility, and particularly large restrictions for industrial-scale producing, in a more simple manner and so that the obtained catalyst has a high activity. This method for manufacturing an ammonia synthesis catalyst includes: a first step for preparing 12CaO.7Al2O3 having a specific surface area of 5 m2/g or above; a second step for supporting a ruthenium compound on the 12CaO.7Al2O3; and a third step for performing a reduction process on the 12CaO.7Al2O3 supporting the ruthenium compound, obtained in the second step. This invention is characterized in that the reduction process is performed until the average particle diameter of the ruthenium after the reduction process has increased by at least 15% in relation to the average particle diameter of the ruthenium before the reduction process.

Abstract: Provided is a method for manufacturing a catalyst with which it is possible to obtain a supported metal ammonia synthesis catalyst, in which there are restrictions in terms of producing method and producing facility, and particularly large restrictions for industrial-scale producing, in a more simple manner and so that the obtained catalyst has a high activity. This method for manufacturing an ammonia synthesis catalyst includes: a first step for preparing 12CaO.7Al2O3 having a specific surface area of 5 m2/g or above; a second step for supporting a ruthenium compound on the 12CaO.7Al2O3; and a third step for performing a reduction process on the 12CaO.7Al2O3 supporting the ruthenium compound, obtained in the second step. This invention is characterized in that the reduction process is performed until the average particle diameter of the ruthenium after the reduction process has increased by at least 15% in relation to the average particle diameter of the ruthenium before the reduction process.