A catalyst for synthesizing aromatic hydrocarbons, a preparation method thereof and a method for synthesizing aromatic hydrocarbons by using the catalyst. The catalyst comprises acidic molecular sieve particles and zinc-aluminum composite oxide particles. The catalyst has relatively high selectivity to aromatic hydrocarbons, particularly BTX, stable performance, and a long single-pass life.

A catalyst contains a metal oxide, and a molecular sieve, in a crystal form, having a topological pore structure. The metal oxide is centrally distributed on the surface of the molecular sieve. Grains of the molecular sieve are exposed to at least three families of crystal planes. The family of crystal plane with the largest pore size in topology is occupied by the metal oxide by no more than 30%, preferably no more than 20%, or no more than 10%.

The present disclosure discloses a multistage nanoreactor catalyst and preparation and application thereof, belonging to the technical field of synthesis gas conversion. The catalyst consists of a core of an iron-based Fischer-Tropsch catalyst, a transition layer of a porous oxide or porous carbon material, and a shell layer of a molecular sieve having an aromatization function. The molecular sieve of the shell layer can be further modified by a metal element or a non-metal element, and the outer surface of the molecular sieve is further modified by a silicon-oxygen compound to adjust the acidic site on the outer surface and the aperture of the molecular sieve, thereby inhibiting the formation of heavy aromatic hydrocarbons. According to the disclosure, the shell layer molecular sieve with a transition layer and a shell layer containing or not containing auxiliaries, and with or without surface modification can be prepared by the iron-based Fischer-Tropsch catalyst through multiple steps. The catalyst can be used for direct preparation of aromatic compounds, especially light aromatic compounds, from synthesis gas; the selectivity of light aromatic hydrocarbons in hydrocarbons can be 75% or above, and the content in the liquid phase product is not less than 95%; and the catalyst has good stability and good industrial application prospect.

The present disclosure discloses a multistage nanoreactor catalyst and preparation and application thereof, belonging to the technical field of synthesis gas conversion. The catalyst consists of a core of an iron-based Fischer-Tropsch catalyst, a transition layer of a porous oxide or porous carbon material, and a shell layer of a molecular sieve having an aromatization function. The molecular sieve of the shell layer can be further modified by a metal element or a non-metal element, and the outer surface of the molecular sieve is further modified by a silicon-oxygen compound to adjust the acidic site on the outer surface and the aperture of the molecular sieve, thereby inhibiting the formation of heavy aromatic hydrocarbons. According to the disclosure, the shell layer molecular sieve with a transition layer and a shell layer containing or not containing auxiliaries, and with or without surface modification can be prepared by the iron-based Fischer-Tropsch catalyst through multiple steps. The catalyst can be used for direct preparation of aromatic compounds, especially light aromatic compounds, from synthesis gas; the selectivity of light aromatic hydrocarbons in hydrocarbons can be 75% or above, and the content in the liquid phase product is not less than 95%; and the catalyst has good stability and good industrial application prospect.

Direct conversion of syngas to light olefins is carried out in a fixed bed or a moving bed reactor with a composite catalyst A+B. The active ingredient of catalyst A is active metal oxide; and catalyst B is one or more than one of zeolite of CHA and AEI structures or metal modified CHA and/or AEI zeolite. A spacing between geometric centers of the active metal oxide of the catalyst A and the particle of the catalyst B is 5 m-40 mm. A spacing between axes of the particles is preferably 100 m-5 mm, and more preferably 200 m-4 mm. A weight ratio of the active ingredients in the catalyst A and the catalyst B is within a range of 0.1-20 times, and preferably 0.3-5.

A methanation catalyst for the methanation of carbon monoxide and/or carbon dioxide is disclosed that provides high selectivity and stability, and additionally shows improved activity compared with prior catalysts. The methanation catalyst for the methanation of carbon monoxide and/or carbon dioxide comprises aluminum oxide, a Ni active mass, and Mn, wherein the Ni/Mn molar ratio in the catalyst is 3.0 to 10.0.

A process for direct synthesis of light olefins uses syngas as the feed raw material. This catalytic conversion process is conducted in a fixed bed or a moving bed using a composite catalyst containing components A and B (A+B). The active ingredient of catalyst A is metal oxide; and catalyst B is an oxide supported zeolite. A carrier is one or more of Al.sub.2O.sub.3, SiO.sub.2, TiO.sub.2, ZrO.sub.2, CeO.sub.2, MgO and Ga.sub.2O.sub.3 having hierarchical pores; the zeolite is one or more of CHA and AEI structures. The loading of the zeolite is 4%-45% wt. A weight ratio of the active ingredients in the catalyst A and the catalyst B is within a range of 0.1-20, and preferably 0.3-5. The total selectivity of the light olefins comprising ethylene, propylene and butylene can reach 50-90%, while the selectivity of a methane byproduct is less than 15%.

A process for direct synthesis of light olefins uses syngas as the feed raw material. This catalytic conversion process is conducted in a fixed bed or a moving bed using a composite catalyst containing components A and B (A+B). The active ingredient of catalyst A is metal oxide; and catalyst B is an oxide supported zeolite. A carrier is one or more of Al.sub.2O.sub.3, SiO.sub.2, TiO.sub.2, ZrO.sub.2, CeO.sub.2, MgO and Ga.sub.2O.sub.3 having hierarchical pores; the zeolite is one or more of CHA and AEI structures. The loading of the zeolite is 4%-45% wt. A weight ratio of the active ingredients in the catalyst A and the catalyst B is within a range of 0.1-20, and preferably 0.3-5. The total selectivity of the light olefins comprising ethylene, propylene and butylene can reach 50-90%, while the selectivity of a methane byproduct is less than 15%.

A cobalt carbide-based catalyst for direct production of olefin from synthesis gas, a preparation method therefor and application thereof are disclosed. The method for preparing the catalyst comprises the following steps: 1) mixing a cobalt source with water, or mixing a cobalt source, an electron promoter and water to obtain a first solution; and mixing a precipitant with water to obtain a second solution; 2) adding the first solution and the second solution to water, or water and a structure promoter for precipitation, crystallizing, separating, drying and calcination; and 3) reducing a solid obtained in Step 2) in a reducing atmosphere, and then carbonizing in a carbonizing atmosphere. The prepared catalyst has high activity and high selectivity to olefins for direct production of olefins via syngas conversion.

A cobalt carbide-based catalyst for direct production of olefin from synthesis gas, a preparation method therefor and application thereof are disclosed. The method for preparing the catalyst comprises the following steps: 1) mixing a cobalt source with water, or mixing a cobalt source, an electron promoter and water to obtain a first solution; and mixing a precipitant with water to obtain a second solution; 2) adding the first solution and the second solution to water, or water and a structure promoter for precipitation, crystallizing, separating, drying and calcination; and 3) reducing a solid obtained in Step 2) in a reducing atmosphere, and then carbonizing in a carbonizing atmosphere. The prepared catalyst has high activity and high selectivity to olefins for direct production of olefins via syngas conversion.