Abstract: Disclosed is a ruthenium-based catalyst for ammonia synthesis, preparation method and use thereof. The ruthenium-based catalyst comprises Ru—Ba-A core-shell structure which comprises a ruthenium nanoparticle as a core covered with a first shell and a second shell sequentially, wherein the first shell consists of a barium nanoparticle, and the second shell consists of a metal oxide. The Ru—Ba-A core-shell structure can effectively preventing agglomerations of ruthenium nanoparticles during the use of the catalyst and avoiding direct contact between the ruthenium nanoparticles and the metal oxides. In addition, barium nanoparticles have a promoting effect as an electronic promoter, which can effectively improve the stability and catalytic activity of ruthenium-based catalyst for ammonia synthesis, especially in the system for synthesizing ammonia from a coal gas.

Abstract: An ammonia decomposition apparatus comprises a casing, a heating zone, a heat exchange zone, a reaction section and a heat exchange coil. The heat exchange coil is spirally wound on an outer wall of the reaction section to efficiently heat ammonia gas. The reaction section has a first reaction zone and a second reaction zone communicated successively, the ammonia gas decomposed into a nitrogen-hydrogen mixture after entering the first reaction zone, with the second reaction zone decomposing for the second time the residual ammonia gas in the nitrogen-hydrogen mixture produced in the first reaction zone, so that the ammonia gas is decomposed more thoroughly. The conversion rate of ammonia gas can reach 99.9% or more, and the residual amount of ammonia gas in the nitrogen-hydrogen mixture can be less than 1000 ppm.

Abstract: Disclosed is a ruthenium-based catalyst for ammonia synthesis, preparation method and use thereof. The ruthenium-based catalyst comprises Ru—Ba-A core-shell structure which comprises a ruthenium nanoparticle as a core covered with a first shell and a second shell sequentially, wherein the first shell consists of a barium nanoparticle, and the second shell consists of a metal oxide. The Ru—Ba-A core-shell structure can effectively preventing agglomerations of ruthenium nanoparticles during the use of the catalyst and avoiding direct contact between the ruthenium nanoparticles and the metal oxides. In addition, barium nanoparticles have a promoting effect as an electronic promoter, which can effectively improve the stability and catalytic activity of ruthenium-based catalyst for ammonia synthesis, especially in the system for synthesizing ammonia from a coal gas.

Abstract: An ammonia decomposition apparatus comprises a casing, a heating zone, a heat exchange zone, a reaction section and a heat exchange coil. The heat exchange coil is spirally wound on an outer wall of the reaction section to efficiently heat ammonia gas. The reaction section has a first reaction zone and a second reaction zone communicated successively, the ammonia gas decomposed into a nitrogen-hydrogen mixture after entering the first reaction zone, with the second reaction zone decomposing for the second time the residual ammonia gas in the nitrogen-hydrogen mixture produced in the first reaction zone, so that the ammonia gas is decomposed more thoroughly. The conversion rate of ammonia gas can reach 99.9% or more, and the residual amount of ammonia gas in the nitrogen-hydrogen mixture can be less than 1000 ppm.