A kind of preparation method of metal matrix porous ceramic composite membrane

Abstract

The present invention provides a method for preparing a metal-based porous ceramic composite membrane, comprising the steps of: S1 obtaining a suspension containing ceramic powder; coating the suspension on the inner surface of a porous ceramic tube to form a ceramic inner coating; S2 applying the porous metal The punching tube is wrapped with wire mesh, and the porous ceramic tube is inserted into the punching tube. A connecting piece is arranged at one end of the punching tube. A cavity is formed between the outer wall of the porous ceramic tube, the inner wall of the wire mesh and the connecting piece; S3 is in the cavity. Fill the metal powder and plug it at the other end of the punching tube to form an assembly; S4 sinter the assembly, the ceramic inner coating forms a ceramic film layer, the metal powder forms a metal film layer, and the wire mesh is removed to obtain a metal film. based porous ceramic composite membrane. The metal wire mesh acts as an outer mold. At high temperature, the metal powder and the punching tube diffuse into each other. Both the punching tube and the wire mesh play a role in positioning the metal powder; only the wire mesh is removed, and the composite with the punching tube The film has higher mechanical strength and the film layer is intact.

Description

technical field [0001] The invention belongs to the technical field of powder metallurgy porous material preparation, and in particular relates to a preparation method of a metal-based porous ceramic composite membrane and a metal-based porous ceramic composite membrane. Background technique [0002] Membranes used in membrane separation equipment can be divided into two categories: organic membranes and inorganic membranes according to their materials. Among them, inorganic membranes can be divided into ceramic membranes and metal membranes. [0003] Organic membranes are prone to be corroded by organic solvents during use, are not resistant to strong acid and alkali corrosion, are not resistant to temperature, and have a short life; compared with organic membranes, ceramic membranes, as a commonly used membrane material, have chemical stability. It has the advantages of high mechanical strength, high temperature resistance and high separation efficiency. However, ceramic ...

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Problems solved by technology

However, in this method, if a metal outer mold is used, the metal powder is easily sintered together, and it is difficult to demold; while using a ceramic mold, the powder sintering shrinks during the sintering process, which will generate axial tensile stress, and the metal film layer is easy to Cracking will not only fail to effectively protect the ceramic membrane, but will also generate internal stress, making the ceramic tube more likely to break; even if the above two problems do not occur, the mold will creep under high temperature conditions, which will also cause the mold to break. Cannot be reused, and the production cost remains high

[0006] Patent CN110899703A discloses a method for preparing a metal film with a high porosity. This method will fill in the metal, and after the sintering is completed, use an acid solution to corrode the metal mold to obtain a metal film. Although this method is suitable for the preparation of the metal film, However, in order to improve the strength of the mold, the wall thickness of the metal outer mold is relatively large, and due to the airtightness of its structure, corrosion will start from the outer layer of the outer mold and the inner side of the inner film. To obtain a complete metal film, it is necessary to It is necessary to completely corrode the mold, which will inevitably require a large amount of acid for corrosion

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