METHOD FOR PRODUCING POWDER OF CONDUCTING CONNECTION OF MAYENITE TYPE Russian patent published in 2018 - IPC C01F7/16 C01F11/02 B01J23/58 B01J32/00 C01C1/04 B01J37/02 

FIELD: chemistry.

SUBSTANCE: first a powder of the precursor of the mayenite-type compound is formed by the hydrothermal treating with a powder mixture of the raw materials of the mayenite-type compound and water. A powder of the mayenite-type compound is then formed by heating and dehydrating the precursor powder. A powder of the activated mayenite-type compound is produced by heating the dehydrated powder in an inert gas atmosphere or in a vacuum in the range of 400°C to 1000°C for at least three hours. The electrons are injected by mixing the powder of the activated mayenite-type compound with a reducing agent - Ca or CaH₂ and heating the resulting mixture from 400°C to 1100°C. The obtained powder of the conductive mayenite-type compound, which is 12CaO⋅7Al₂O₃, has a concentration of the conduction electrons of at least 10¹⁵ cm^-3 and a specific surface of at least 5 m²g^-1. After these heating steps, rapid thermal annealing can be repeated by increasing the temperature at a rate of 30 to 60°C min^-1 and its maintenance at heating in a range of temperatures from 900°C to 1100°C. The metal catalyst containing medium in the form of the resulting conductive mayenite-type compounds and the applied catalyst based on transition metal, is used in the method of ammonia synthesis by the reaction of gaseous nitrogen (N₂) and hydrogen (H₂) thereon.

EFFECT: invention allows to produce a mayenite-type compound having simultaneously a large specific surface area and a high conductivity.

9 cl, 2 tbl, 13 ex