Preparation method of metal-based porous ceramic composite membrane

Abstract

The invention provides a preparation method of a metal-based porous ceramic composite membrane. The preparation method comprises the following steps: S1, obtaining a suspension containing ceramic powder; coating the suspension liquid on the inner surface of a porous ceramic tube to form a ceramic inner coating; s2, the porous metal punching pipe is wrapped with a metal wire mesh, the porous ceramic pipe is plugged into the punching pipe, a connecting piece is arranged at one end of the punching pipe, and a cavity is formed among the outer wall of the porous ceramic pipe, the inner wall of the wire mesh and the connecting piece; s3, the cavity is filled with metal powder, the other end of the punched pipe is plugged, and an assembly is formed; and S4, sintering the assembly, forming a ceramic film layer by the ceramic inner coating, forming a metal film layer by the metal powder, and removing the metal wire mesh to obtain the metal-based porous ceramic composite film. The metal wire mesh serves as an outer die, metal powder and the punched pipe are mutually diffused at high temperature, and the punched pipe and the wire mesh play a role in positioning the metal powder; only the metal wire mesh is removed, and the composite film with the punching pipe has higher mechanical strength and is complete in film layer.

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] The 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 more likely 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 at present, have chemical stability. Good, high mechanical strength, high temperature resistance, high separation efficiency and other advantages...

AI Technical Summary

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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