compound zro 2 ‑al 2 o 3 Preparation method of ceramic microfiltration membrane

Abstract

The invention discloses a preparation method of a composite ZrO2-Al2O3 ceramic micro-filtration membrane. The method comprises the following steps: (1) burdening zirconia powder and alumina powder, and carrying out ball-milling; (2) adding an additive lanthanum nitrate, and carrying out ball-milling; and (3) forming a film from the milled slurry, drying and sintering. The powder components of the composite membrane layer prepared by the preparation method gradually change; the pore size distribution of the membrane layer is relatively narrow; the thickness of the membrane layer is moderate, so that the micro-filtration membrane has relatively high permeation flux and separation coefficient; the particle size collocation of the powder of a transition membrane layer is reasonable; the surface roughness of the membrane layer is improved; relatively large membrane layer pollution is not easily caused in the actual separation process; zirconia with good chemical stability is utilized in the membrane layer; and the acid and alkali resistance of the membrane layer is improved. The price of the zirconia is higher than that of aluminum oxide, but the amount in preparation of the membrane layer is relatively small; meanwhile, the service life of an inorganic membrane can be prolonged; and the composite ZrO2-Al2O3 ceramic micro-filtration membrane is better than a simple aluminum oxide ceramic membrane or zirconia ceramic membrane in the market at present in performance.

Description

technical field [0001] The present invention relates to composite ZrO 2 -Al 2 o 3 The invention discloses a method for preparing a ceramic microfiltration membrane, belonging to the field of ceramic membrane preparation. Background technique [0002] With the increase of human awareness of environmental protection and the improvement of existing membrane technology, the advantages of membrane separation, such as high separation efficiency and no secondary pollution, have been appreciated by more and more manufacturers, especially the chemical stability of inorganic membranes. Good performance, high mechanical strength, and long service life; the system is easy to operate, stable in operation, and low in maintenance costs; integrated equipment can be used for biochemical treatment, and the whole process can be automatically controlled. Compared with the characteristics of organic membranes, it is widely used by many manufacturers. Applied in caustic environment, such as hi...

AI Technical Summary

Problems solved by technology

No matter which method is used, if the sintered strength is good and the cost is relatively low, Al 2 o 3 As a support, there will be ZrO 2 film and Al 2 o 3 Due to the difference in material properties between supports (ZrO 2 The coefficient of thermal expansion is 10.8×10 -6 , Al 2 o 3 The coefficient of thermal expansion is 8.8×10 -6 ) caused by heat treatment performance mismatch

The stress accumulated by the mismatch of heat treatment performance will directly lead to defects such as microcracks in the film layer during drying and sintering, which will seriously affect the ZrO 2 Performance of Microfiltration Membranes