Preparation method of high-penetration-flux externally-pressed ceramic membrane, and products prepared from high-penetration-flux externally-pressed ceramic membrane

Abstract

The invention discloses a preparation method of a high-penetration-flux externally-pressed ceramic membrane. The preparation method comprises following steps: small particle size powder is prepared into separation membrane ceramic slices; externally pressed membrane pasting is adopted so coat the external surface of a macroporous support body with the separation membrane ceramic slices so as to obtain a separation membrane layer-support body double structure. The invention also discloses products prepared using the preparation method of the high-penetration-flux externally-pressed ceramic membrane. Film pasting external pressing is adopted, a small aperture separation membrane layer is prepared on the macroporous support body directly, so that ceramic membrane penetration flux is increasedeffectively; the separation membrane layer thickness is uniform, and no defect is detected, so that the membrane separation performance is excellent; and in addition, preferable combination with themacroporous support body is realized, so that a membrane layer shedding problem is solved.

Description

technical field [0001] The invention relates to the technical field of membrane separation, in particular to a method for preparing a ceramic separation membrane and a product thereof. Background technique [0002] The ceramic membrane is made of Al 2 o 3 , ZrO 2 、TiO 2 , SiO 2 , SiC and other raw materials are made by a series of special processes and have a porous structure. It is a multi-layer asymmetric structure and consists of two or more layers of membrane layers, generally including a support body, a transition layer and a separation membrane layer. . The support body usually needs to use powder with larger particle size to obtain larger pore size, so that it has good permeability and high mechanical strength. The separation membrane layer plays the role of sieving and separation. Usually, smaller powder is used to reduce the pore size of the membrane and improve the sieving effect. At present, the preparation of ceramic membranes mainly adopts the impregnatio...

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Problems solved by technology

In this way, different powder particle sizes and calcination temperatures make the process complex, long production cycle, and high energy consumption; moreover, the separation membrane layer will be affected by the defects of the support layer and cause membrane layer defects; at the same time, the existence of the transition layer also Increase the permeation resistance of the ceramic membrane, reduce the permeation flux, and affect the separation efficiency of the ceramic membrane

[0003] In order to improve the permeation flux of the ceramic separation membrane, the existing technology also adopts the method of reducing the transition layer. For example, the support body and the separation membrane layer are made of powder raw materials with the same particle size through low-temperature sintering, but this correspondingly brings There is a problem that the pore size of the separation membrane layer becomes larger, thereby reducing the permeation selectivity of the membrane

Alternatively, use an organic solution to treat the surface of the support with a larger pore size, and use a film-forming liquid with a smaller sol particle size to coat the film, and quickly gel to form a film, but this method adds a large amount of organic matter, and these organic matter in In the process of calcination and removal, a large number of voids will be generated, which will affect the bonding strength between the separation membrane layer and the support, and thus bring about the defect of easy release of the membrane

[0004] In addition, the prior art has also researched and developed techniques such as spraying method, screen printing method, and casting method to prepare film layers, but these methods have higher requirements on the flatness of the support body, and are only suitable for surfaces with larger planes. Flat ceramic membrane

At the same time, regardless of the dipping method or the spraying method, it is easy to cause the problem of uneven particle accumulation due to insufficient dispersion of ceramic powder particles, which leads to the defect of large pores in the film layer.

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