The present application relates to a cerium-tin-based composite oxide catalyst for catalyzing purification of a nitrogen oxide, a preparation method and an application thereof. The catalyst has the following chemical composition: a cerium-tin oxide and an M oxide, wherein the M is selected from any one of or a combination of at least two of P, Ti, Zr, V, Mn, Fe, Cu, Al, Si, Ni, Hf, Nb, Ta, Cr, Mo, W, or Re. According to the present application, a cerium-tin-based composite oxide catalyst having the characteristics such as high catalytic activity, high hydrothermal stability, excellent N.sub.2 generation selectivity, a wide operation temperature window, and adaptation to high space velocity reaction conditions is prepared by means of a non-toxic and harmless raw material and a simple method, and the present application is applicable to a device for catalyzing purification of a mobile source nitrogen oxide represented by diesel vehicle exhaust gas and a fixed source nitrogen oxide represented by flue gas from a coal-fired power plant.

Described herein are reusable, mesh-based catalysts with superior mechanical stability and magnetic separability wherein the mesh may be formed in a variety of shapes and can be easily separated from a process stream and in combination with biomass torrefaction, reduces toxic emissions and produce hydrogen gas, which can be burned at the facility to generate heat or electricity.

High surface area, high entropy oxides comprising multiple metal cations in a single-phase fluorite lattice material enables intrinsic catalytic activity without platinum group metals, tunable oxygen storage capacity, and thermal stability. These properties can be obtained through a facile sol-gel synthesis to provide a low-temperature route for production of phase-pure multi-cationic oxides. The resulting materials achieved significantly higher surface area and catalytic performance, taking advantage of all the properties endowed by the various cations in the composition.

Embodiments of catalyst systems and methods of synthesizing catalyst systems are provided. The catalyst system may include a core comprising a zeolite; and a shell comprising a microporous fibrous silica. The shell may be in direct contact with at least a majority of an outer surface of the core. The catalyst system may have a Si/Al molar ratio greater than 5. At least a portion of the shell may have a thickness of from 50 nanometers (nm) to 600 nm.

Disclosed herein is a catalyst composite containing a perovskite-oxide and an oxide support, methods of preparing a catalyst composite containing a perovskite-oxide and an oxide support, and the use thereof for CO.sub.2 conversion by a reverse water gas shift chemical looping (RWGS-CL) process.

The present invention relates to a method for preparing ZSM-5 zeolite. The present invention can provide a method for preparing ZSM-5 zeolite comprising the steps of: preparing a first solution in a solution state by heating a mixture comprising a silica source, an alumina source, a neutralizing agent and a crystalline ZSM-5 nucleus; preparing a reaction mother liquid by mixing a second solution comprising salts into the first solution; and continuously crystallizing by continuously supplying the reaction mother liquid to a hydrothermal synthesis reactor, wherein formula [1] below is satisfied.
0.20≤W.sub.a/W.sub.b≤0.40  Formula [1]

Disclosed herein are methods for the preparation of porous metal oxide materials, including metal oxide xerogels and metal oxide aerogels. Methods for preparing porous metal oxide materials can comprise (i) reacting a metal alkoxide with water in the presence of a catalyst system to form a partially hydrolyzed sol, (ii) contacting the partially hydrolyzed sol with a base catalyst and a non-aqueous solvent to form a precursor gel; and (iii) drying the precursor gel to form the porous metal oxide material. The catalyst system employed in step (i) comprises a combination of a weak acid and a strong acid.

Incorporating a bimetal to a lamellar MFI zeolite structure includes providing a bimetallic-incorporated lamellar zeolite catalyst including a sodium source, aluminum source, silicon source, surfactant, sulfuric acid, deionized water, metal source, and molecular template; dissolving the sodium source in the deionized water creating a basic solution; adding the sulfuric acid, aluminum source, molecular template, and silicon source to the basic solution creating a mixture and adding the metal source to the mixture; dissolving the surfactant in the deionized water creating a surfactant solution; combining the surfactant solution and basic solution; heating the combined surfactant solution and basic solution in a rotating autoclave creating a metal-containing zeolite including the surfactant and molecular template in a structure of the metal-containing zeolite; removing a synthesized zeolite from the autoclave; drying the synthesized zeolite and creating a dry zeolite powder; calcining the dry zeolite powder creating a bimetal-containing lamellar MFI zeolite for chemical activation.

The present disclosure relates to the technical field of catalysts, and specifically to a Zn—Al slurry catalyst, its preparation method and its application in preparing ethanol from syngas. The preparation method provided in the disclosure prepares the Zn—Al slurry catalyst by introducing a zinc component into an aluminum sol, and the preparation method has a simple operation and a lower cost. The Zn—Al slurry catalyst prepared in the disclosure includes the Zn component and the Al component, which may catalyze syngas to generate ethanol under mild conditions. Also, the catalyst has stable properties, is not easy to be deactivated, and reduces the cost of preparing ethanol from syngas. When the Zn—Al slurry catalyst provided in the disclosure is used as the catalyst for preparing ethanol from syngas, the reaction conditions are mild, and the syngas may be catalyzed to generate ethanol under the conditions of 250-340° C. and 3-5 MPa.

Embodiments of catalyst systems and methods of synthesizing catalyst systems are provided. The catalyst system may include a core comprising a zeolite; and a shell comprising a microporous fibrous silica. The shell may be in direct contact with at least a majority of an outer surface of the core. The catalyst system may have a Si/Al molar ratio greater than 5. At least a portion of the shell may have a thickness of from 50 nanometers (nm) to 600 nm.