Preparation method for molecular sieve coating material on porous silicon carbide ceramic surface

The invention relates to a preparation technique for a molecular sieve coating material, in particular to a preparation method for a molecular sieve coating material on a porous silicon carbide ceramic surface. Porous silicon carbide ceramic is used as a carrier, solid raw materials such as silicon blocks, quartz, silicon-aluminum composite oxide sintered powder with adjustable silicon-aluminum atomic ratio and the like are used as a silicon source or a silicon-aluminum source, and the raw materials are synthesized through in-situ hydrothermal reaction. The porous silicon carbide ceramic surface is provided with microporous structures. The use of the solid silicon source or silicon-aluminum source can enable the release speed of the silicon source or silicon-aluminum source for the growth of crystal nucleus to be controllable. Thereby, the prepared molecular sieve coating is evenly loaded on the surface of the silicon carbide ceramic carrier, the silicon-to-aluminum ratio can be accurately controlled, and the composite material formed by the molecular sieve and the porous silicon carbide ceramic has unique microporous/macroporous structures; and the chemical bonding between the molecular sieve and the porous silicon carbide ceramic is realized and the interfacial bonding strength is high. The invention has the advantages that the technology of the method is simple, the operation is convenient, the complex equipment is not required, the preparation cost is low and the method is more suitable for industrialized mass production.