CN110981529A - Porous ceramic membrane material and preparation method and application thereof - Google Patents

Porous ceramic membrane material and preparation method and application thereof Download PDF

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CN110981529A
CN110981529A CN201911350627.9A CN201911350627A CN110981529A CN 110981529 A CN110981529 A CN 110981529A CN 201911350627 A CN201911350627 A CN 201911350627A CN 110981529 A CN110981529 A CN 110981529A
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whisker
sodium alginate
solution
porous ceramic
ceramic membrane
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徐国纲
陈之伟
崔洪芝
郝伟然
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Shandong University of Science and Technology
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Shandong University of Science and Technology
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    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B38/00—Porous mortars, concrete, artificial stone or ceramic ware; Preparation thereof
    • C04B38/0045—Porous mortars, concrete, artificial stone or ceramic ware; Preparation thereof by a process involving the formation of a sol or a gel, e.g. sol-gel or precipitation processes
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D67/00—Processes specially adapted for manufacturing semi-permeable membranes for separation processes or apparatus
    • B01D67/0039—Inorganic membrane manufacture
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D71/00—Semi-permeable membranes for separation processes or apparatus characterised by the material; Manufacturing processes specially adapted therefor
    • B01D71/02—Inorganic material
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00—Treatment of water, waste water, or sewage
    • C02F1/44—Treatment of water, waste water, or sewage by dialysis, osmosis or reverse osmosis
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/01—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics
    • C04B35/10—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics based on aluminium oxide
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/622—Forming processes; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/62218—Forming processes; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products obtaining ceramic films, e.g. by using temporary supports
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/71—Ceramic products containing macroscopic reinforcing agents
    • C04B35/78—Ceramic products containing macroscopic reinforcing agents containing non-metallic materials
    • C04B35/80—Fibres, filaments, whiskers, platelets, or the like
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B38/00—Porous mortars, concrete, artificial stone or ceramic ware; Preparation thereof
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B38/00—Porous mortars, concrete, artificial stone or ceramic ware; Preparation thereof
    • C04B38/0051—Porous mortars, concrete, artificial stone or ceramic ware; Preparation thereof characterised by the pore size, pore shape or kind of porosity
    • C04B38/0054—Porous mortars, concrete, artificial stone or ceramic ware; Preparation thereof characterised by the pore size, pore shape or kind of porosity the pores being microsized or nanosized
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
    • C04B2235/50—Constituents or additives of the starting mixture chosen for their shape or used because of their shape or their physical appearance
    • C04B2235/52—Constituents or additives characterised by their shapes
    • C04B2235/5276—Whiskers, spindles, needles or pins

Abstract

The invention provides a porous ceramic membrane material and a preparation method and application thereof, wherein the method comprises the following steps: under the water bath environment, adding a sodium alginate solution in the process of preparing the raw material powder into ceramic slurry, mixing the sodium alginate solution with an ethylene diamine tetraacetic acid calcium solution and gluconolactone, carrying out directional freezing hole control after in-situ gel solidification, and sintering to obtain the porous ceramic membrane material, wherein the material has a directional stepped hole structure, controllable pore diameter and high porosity. The method solves the problems of low flux, complex process, long production period, uncontrollable aperture, single pore structure, low mechanical strength, uncontrollable shape and thickness and the like of the porous ceramic membrane prepared by the prior art, and compared with other preparation methods of the alumina whisker porous ceramic membrane, the method has the advantages of simple preparation process, high efficiency, low cost, environmental protection and capability of being popularized and applied in a large scale.

Description

Porous ceramic membrane material and preparation method and application thereof
Technical Field
The invention relates to the technical field of porous ceramics and membrane separation, in particular to a porous ceramic membrane material and a preparation method and application thereof.
Background
The information in this background section is only for enhancement of understanding of the general background of the invention and is not necessarily to be construed as an admission or any form of suggestion that this information forms the prior art that is already known to a person of ordinary skill in the art.
The inorganic ceramic membrane has the characteristics of high temperature resistance, good chemical stability (acid and alkali resistance and organic solvent resistance), high mechanical strength, strong antimicrobial capability, narrow pore size distribution range, high separation efficiency and the like, is widely applied to the industries of environmental protection water treatment, chemical engineering and petrochemical industry, food, pharmacy, papermaking, metallurgy and the like, is suitable for the fields of solid-liquid separation, oil-water separation, impurity removal separation, cutting fluid recovery, pure water concentration and the like, and becomes one of competitive hot spots in the modern high and new technology field.
The alumina ceramic has the advantages of chemical erosion resistance, wear resistance, light weight, low expansion coefficient, excellent high temperature stability and the like, so the alumina ceramic has wide application prospect in the fields of membrane material filtration and the like. Different preparation methods directly influence the pore structure and pore size of the membrane. Currently, industrial methods for producing aluminum oxide films mainly include dry press molding, slip casting, tape casting, extrusion molding, sol-gel method, and the like. However, the above preparation methods all have their limitations, for example, the porosity of the sample prepared by the dry pressing method is low; the pore diameter distribution of the microfiltration membrane support prepared by the grouting method is wider, the sizes of products have larger difference, and defects are easy to occur; extrusion molding is suitable for continuous batch production, has high production efficiency and is easy to operate automatically, but the ceramic pug needs to be subjected to vacuum pug refining and aging, particularly for barren raw materials, the process period is long, and the process is relatively complex. Since the ceramic filter membrane material must have a high permeability to satisfy the requirements of smooth fluid passage and reduction of internal and external pressures, the porous alumina ceramic membrane must have a high porosity and requires a directional pore distribution. However, it is difficult to obtain an alumina porous ceramic film having a porosity of more than 80%, a pore diameter of 0.1 to 100 μm, and an oriented pore structure by the above methods. Therefore, how to prepare the high-flux alumina porous ceramic membrane material with high porosity, controllable directional gap and good mechanical property is a problem to be solved urgently. In recent years, a method for freeze-drying gel is provided, the method combines the advantages of the porous structure of the gel and the unique pores formed by sublimating the ice particles growing directionally in the colloid, and the porous alumina ceramic material with high pores and directionally distributed pores can be obtained, so that the method is an ideal process for preparing the porous filter material.
Certain research work is carried out on the aspect of preparing porous ceramics by using gel freeze drying as a method, more researchers use an acrylamide gel system, such as Chen Yu peak and the like (Ruifeng Chen, Yong Huang, Changan Wang, et al, ceramics with ultra low density fabricated by gelcasting: an unconventional overview. journal of the American Ceramic Society,2007,90: 3424-. The monomer used in the system has strong neurotoxicity, so that the development and the wider application of the monomer are prevented.
Some researchers are dedicated to the research of low-toxicity and even non-toxicity system gel freeze-drying technology, and a natural non-toxic high-molecular sodium alginate system is used for replacing an acrylamide system with strong toxicity. Eljaouhara et al (Eljaouhara AA, Muller R, Kellereier M, et al, New anistropic ceramic membranes from chemical structural structures Langmuir,2006,22(26): 11353-; dittrich et al (Dittich R, Tomantl G, despung F, et. Scaffolds for hard tissue engineering by ionotropic gel ofJournal of the American ceramic society,2007,90(6): 1703) 1708) hydroxyapatite porous ceramics having a tubular structure was also prepared using the same sodium alginate ionic gel; xue et Al (Xue W J, Sun Y, Huang Y, et Al preparation and properties of pore aluminum with high ordered and indirect oriented pores by ASELF-organization process, journal of the American Ceramic Society,2011,94(7):1978-2O3Porous ceramics with 170-200 μm pore size and 70% porosity (>88% open pore). In general, the sodium alginate system gel freeze-drying preparation process has many advantages, such as no toxicity in the production process and high porosity (mostly through holes) of the prepared sample, so that the sodium alginate system gel freeze-drying preparation process has high potential market application value, but the development and application of the sodium alginate system gel freeze-drying preparation process also encounter certain bottlenecks. The inventor finds that firstly, the current production process is complex and time-consuming, the permeation speed of divalent ions in the sample gelling process and the aperture length formed by through holes cannot be accurately controlled, so that the sample flux cannot reach the expected target, only a sample with a film thickness can be obtained, and the preparation of a sample with a thicker size and a complex shape is difficult. Secondly, sodium alginate solutions possess the basic physical properties of high viscosity, whereas in gelling, the viscosity of the solution cannot be too high, i.e. the solids content of the slurry is required to be too high, for better penetration of the ions, thus resulting in poor sample strength. In addition, the sample prepared by the method has a single pore structure, and cannot meet the diversified requirements of the application field. The problems that limit their development and application are urgently needed to be solved.
Disclosure of Invention
In order to solve the technical problems, the invention provides a high-flux porous alumina ceramic membrane with an oriented hierarchical pore structure and a preparation method thereof. Aiming at the existing complex production cycle of the process of preparing the alumina porous ceramic membrane by sodium alginate ionic gel-freeze dryingThe invention adopts in-situ Ca release in ceramic slurry2+The method ensures that the sodium alginate in-situ gel is solidified, the pore structure is regulated and controlled by crystallizing water through directional cold sources with different temperatures, the processes of complex and long-time-consuming ion vertical permeation, ion exchange, solvent exchange and the like of the process are replaced, the sample membrane material simultaneously has the gradient pore structures of the separation layer and the support layer, the pore diameter is controllable, the process is simple, the production period is greatly shortened, a thicker sample with complex appearance can be prepared, the sample flux can reach the expected target, the method is suitable for the field of filtration and separation, and the filtration efficiency is high.
In addition, the invention uses the aluminum oxide whiskers as raw materials, the whiskers are mutually overlapped to form a pore wall, uniform nano pores are distributed on the pore wall, and the membrane flux is further improved and the filtering performance is optimized by combining a gel curing directional pore-forming process. Within a certain temperature range, the viscosity of the sodium alginate solution is reduced along with the increase of the temperature. In the preparation process, the invention provides that the silica sol, the sodium alginate solution and the alumina crystal whisker are mixed in a water bath environment at the temperature of 80-90 ℃, and the silica sol and the sodium alginate solution sequentially wrap the alumina crystal whisker, thereby promoting the dispersion of the crystal whisker and solving the problems of crystal whisker agglomeration and overhigh viscosity of the sodium alginate solution. The prepared ceramic slurry is easy to pour into various moulds, fittings with complex shapes can be prepared, and the formed biscuit has enough strength for processing and cutting due to the sodium alginate polymerized gel. More importantly, in the prior art, porous ceramics with different pore diameters are difficult to obtain through ion permeation exchange gel. In the preparation method, the size of the ice crystal can be easily controlled by utilizing different refrigeration temperatures, the aperture can be controlled, and the preparation method has wide application prospect.
In order to achieve the technical effects, the technical scheme of the invention is as follows:
in a first aspect of the present invention, there is provided a method for preparing a porous ceramic membrane material, the method comprising: under the water bath environment, adding a sodium alginate solution in the process of preparing the raw material powder into ceramic slurry, mixing with an ethylene diamine tetraacetic acid calcium solution and gluconolactone, carrying out directional freezing hole control after in-situ gel solidification, and sintering to obtain the porous ceramic membrane material.
In the method, the calcium ethylene diamine tetraacetate solution is prepared from disodium ethylene diamine tetraacetate and calcium carbonate.
The temperature of the water bath is 80-90 ℃.
In an embodiment of the invention, the in situ gel curing comprises: the gluconolactone provides hydrogen ions, calcium ethylene diamine tetraacetic acid combines the hydrogen ions to release calcium ions, and sodium alginate and the calcium ions are chelated in situ to form a network chain structure.
In an embodiment of the invention, the directional freeze control orifice comprises: the water is crystallized by regulating the temperature of a cold source, the size of ice crystals is regulated, after the ice crystals are completely grown by freezing, the frozen ice crystals are sublimated and discharged by vacuum freeze drying under a low-pressure vacuum environment, and thus a directional porous structure is formed; the cold source is liquid nitrogen or ultra-low temperature refrigerator and other relatively cold materials or machines.
The raw material powder is a main component required for preparing ceramics, for example, the raw material is alumina whisker when preparing an alumina whisker porous ceramic membrane material. Therefore, it is within the ability of those skilled in the art to select appropriate raw material powder based on the porous ceramic membrane material to be prepared according to the above technical solution of the present invention.
In a second aspect of the invention, the invention provides a method for preparing an alumina whisker porous ceramic membrane material, which comprises the following steps: under the condition of water bath, adding sodium alginate solution into alumina whisker as a raw material, mixing with ethylene diamine tetraacetic acid calcium solution and gluconolactone to form ceramic slurry, solidifying in-situ gel, performing directional freezing and pore control, and sintering to prepare the alumina whisker porous ceramic membrane material.
In an embodiment of the invention, the weight ratio of the calcium ethylenediaminetetraacetate solution, the gluconolactone and the sodium alginate solution is (2-10): 0-3): 10-25, preferably (2-10): 0.2-3): 10-25, and more preferably 6:1: 20.
In an embodiment of the invention, the curing time is 4-24 h.
In an embodiment of the invention, the freezing temperature is-196 ℃ to-20 ℃.
In an embodiment of the invention, the freezing time is between 0.5h and 10 h.
In an embodiment of the invention, the sintering conditions are: the sintering temperature is 1300-1600 ℃, and the heat preservation time is 2-3 hours.
In some embodiments of the invention, the ceramic slurry further comprises magnesium oxide, glycerin, PVA, and silica sol.
In these embodiments, the method of preparing the ceramic slurry includes: uniformly mixing the aluminum oxide whisker, the magnesium oxide, the glycerol, the PVA, the silica sol, the deionized water and the sodium alginate solution, then adding the calcium ethylene diamine tetracetate solution, and adding the gluconolactone during stirring to fully mix the materials to form uniform ceramic slurry.
In the embodiment of the invention, the mass ratio of the alumina whisker, the magnesium oxide, the silica sol, the PVA, the glycerol, the deionized water and the sodium alginate solution is (100-: (1-6): (3-16): (0-71): (3-15): (157-419): (26-211).
In the embodiment of the invention, the mass ratio of the alumina whisker, the magnesium oxide, the silica sol, the PVA, the glycerol, the deionized water and the sodium alginate solution is (100-: (1-6): (3-16): (1-71): (3-15): (157-419): (26-211).
In an embodiment of the invention, the alumina whiskers are γ -Al2O3A whisker.
The invention provides a method for preparing alumina whiskers, which comprises the following steps: dissolving aluminum nitrate in deionized water to obtain an aluminum nitrate solution, adding urea and polyethylene glycol, uniformly mixing, pouring into a reaction kettle for hydrothermal treatment to obtain aluminum ammonium carbonate whiskers, dispersing the aluminum ammonium carbonate whiskers, and sintering to obtain gamma-Al2O3Whisker; the alumina crystal whisker prepared by the method is used as a porous ceramic membrane material prepared by raw materials, and has better membrane flux and filtering performance.
In an embodiment of the present invention, the concentration of the aluminum nitrate solution is 1.07 to 1.5 mol/L.
In an embodiment of the present invention, the mass ratio of polyethylene glycol to aluminum nitrate is (0-1): (1-5), preferably (0.02-1): (1-5), more preferably 1: 1.
In an embodiment of the invention, the urea conditioning solution has a pH of 9 to 10.
In the embodiment of the invention, in the preparation process of the alumina whisker, the hydrothermal temperature is 120-200 ℃, and the hydrothermal time is 12-48 h.
In the embodiment of the invention, the aluminum ammonium carbonate whisker is dispersed in a manner selected from one or more of alcohol washing, ultrasonic stirring and heating stirring; the dispersion method is preferably a dispersion method in which the alcohol is washed, ultrasonically stirred, and then heated and stirred.
In the embodiment of the invention, the ammonium aluminum carbonate whiskers are dispersed for 30-120 min.
In an embodiment of the invention, the sintering yields γ -Al2O3The temperature of the whisker is 600-800 ℃.
In the embodiment of the invention, the sodium alginate solution is deionized water solution of sodium alginate, and the concentration of the deionized water solution is 2-5 mol/L. The invention provides a specific method for preparing sodium alginate, which comprises the following steps: adding sodium alginate powder into deionized water at 80-90 deg.c and stirring for 0.5-2 hr.
In an embodiment of the invention, the calcium ethylene diamine tetraacetate solution is prepared by adding disodium ethylene diamine tetraacetate and calcium carbonate into deionized water and mixing.
In some embodiments of the invention, the mass ratio of the disodium ethylene diamine tetraacetate, the calcium carbonate and the deionized water is (30-50): (1-6): (1-2), preferably 50:4: 1.
In some embodiments of the invention, the invention provides a preparation method of the alumina whisker porous ceramic membrane material, which comprises the following steps:
adding urea into an aluminum nitrate solution to adjust the pH, then adding polyethylene glycol, uniformly mixing, performing hydrothermal reaction in a reaction kettle to obtain ammonium aluminum carbonate whiskers, dispersing the ammonium aluminum carbonate whiskers, and sintering to obtain gamma-Al2O3A whisker.
Under the condition of water bath, gamma-Al is added2O3Adding the crystal whisker, the magnesium oxide, the glycerol, the PVA and the silica sol into deionized water, adding an ethylene diamine tetraacetic acid calcium solution, and adding the glucolactone during stirring to fully mix the materials to form uniform ceramic slurry.
In the preparation process of the ceramic slurry, the gamma-Al can be stirred by magnetic force2O3The method comprises the steps of uniformly stirring whiskers, magnesium oxide, glycerol, PVA and silica sol in deionized water, uniformly coating the silica sol on the surfaces of the whiskers, promoting the dispersion of the whiskers, adding a sodium alginate solution according to the proportion requirement, continuously coating the sodium alginate solution on the surfaces of the alumina whiskers, further improving the dispersion of the alumina whiskers, and further improving the uniformity of slurry.
Pouring the ceramic slurry into a mold rapidly, carrying out in-situ gel solidification in a moisture preserving box, wherein, gluconolactone provides hydrogen ions, calcium ethylene diamine tetracetate combines the hydrogen ions to release calcium ions, triggering sodium alginate and the calcium ions to chelate in situ to form a network chain structure, directionally freezing and controlling pores after solidification, comprising utilizing liquid nitrogen as a directional cold source, utilizing different refrigeration temperatures to regulate and control the size of ice crystals, freezing to ensure the complete development of the ice crystals, carrying out vacuum freeze drying, comprising placing a frozen body in a low-pressure environment to sublimate and discharge the frozen ice crystals, obtaining a dry porous ceramic blank body with a directional gradient pore structure along the gradient direction of the freezing temperature, and sintering to obtain the alumina whisker porous ceramic membrane material.
In the embodiment of the invention, the inventor finds that the content of the sodium alginate solution influences the porosity and the pore diameter of the alumina whisker porous ceramic membrane material: within the scope of the invention, for example, the concentration of the sodium alginate solution is 2-5mol/L, and the mass ratio of the alumina whisker, the magnesium oxide, the silica sol, the PVA, the glycerol, the deionized water and the sodium alginate solution is (100-: (1-6): (3-16): (0-71): (3-15): (157-419): (26-211), in the range, the higher the content of the sodium alginate solution is, the higher the porosity is, and the larger the pore diameter is. The solid contents (the mass of the alumina whisker, the mass of the magnesia and the mass of the silica in the silica sol) are different, and the solid contents affect the porosity and the aperture of the alumina whisker porous ceramic membrane material: within the scope of the invention, the higher the mass of the alumina whiskers, the mass of the magnesium oxide and the mass of the silica in the silica sol, i.e. the higher the solid content, the lower the porosity and the smaller the pore size. The refrigeration temperature affects the pore size: within the scope of the invention, the lower the refrigeration temperature, the smaller the pore size. Sintering temperature affects porosity: within the scope of the invention, the higher the sintering temperature, the lower the porosity. The sintering temperature affects the compressive strength of the material: within the scope of the invention, the higher the sintering temperature, the higher the compressive strength.
In a third aspect of the present invention, the present invention provides a porous ceramic membrane material prepared by the method of the first aspect; and the alumina whisker porous ceramic membrane material prepared by the method of the second aspect.
The porous ceramic membrane material or the alumina whisker porous ceramic membrane material simultaneously has a gradient pore structure of a separation layer and a support layer, the pore diameter is controllable, the average pore diameter is 0.78-1 mu m, the filtering precision is higher, the porosity is higher than 80 percent, and the nitrogen flux is as high as 1.52 multiplied by 106L/m2H.bar, and therefore also higher filtration efficiency.
In a fourth aspect of the invention, the invention also provides application of the porous ceramic membrane material or the alumina whisker porous ceramic membrane material in the third aspect in oil-water separation, industrial water treatment, industrial circulating cooling water purification and production water treatment.
Compared with the prior art, the invention has the following beneficial effects:
1. according to the invention, the high-flux alumina whisker porous ceramic membrane is prepared by a gel curing pore-forming process, sodium alginate in-situ gel curing is utilized, the sizes of ice crystals are directionally regulated and controlled by directional refrigeration at different temperatures, and after the ice crystals are sublimated and discharged, the porous alumina ceramic membrane with a directional gradient pore structure (a separation layer and a support layer), controllable pore diameter and high porosity can be obtained in one step.
2. The method adopts in-situ release of Ca2+The method ensures that the sodium alginate is uniformly gelled in situ, the water is vertically frozen and grows in a directional refrigeration mode, the processes of vertical penetration of ions, ion exchange, solvent exchange and the like are replaced, the problems of complex process, long production period, uncontrollable pore diameter, single pore structure and the like are solved, the prepared sample contains a directional gradient pore structure (a separation layer and a support layer), the pore diameter is controllable, the sample flux can reach the expected target, the method is suitable for the field of filtration and separation, and the filtration efficiency is high. .
3. The invention provides a method for preparing a nano-porous membrane by using alumina whiskers as a raw material, mutually overlapping the whiskers on the pore wall to form a uniform nano-porous structure, and combining a gel curing directional pore-forming process, thereby further improving the membrane flux and optimizing the filtration performance.
4. The method introduces a water bath environment of 80-90 ℃, under the condition, the alumina crystal whiskers, the silica sol and the sodium alginate solution are mixed, and the alumina crystal whiskers are uniformly coated by the silica sol and the sodium alginate solution in sequence, so that the dispersion of the crystal whiskers is promoted, and the problems of crystal whisker agglomeration and overhigh viscosity of the sodium alginate solution are solved. The prepared ceramic slurry is easy to pour into various moulds, fittings with complex shapes can be prepared, and the formed biscuit has enough strength for processing and cutting due to the sodium alginate polymerized gel.
5. In the sodium alginate system, the invention utilizes different refrigeration temperatures to control the size of the ice crystals, replaces the ion permeation exchange process, solves the problem of uncontrollable pore diameter and has wide application prospect.
Drawings
The accompanying drawings, which are incorporated in and constitute a part of this specification, are included to provide a further understanding of the invention, and are incorporated in and constitute a part of this specification, illustrate exemplary embodiments of the invention and together with the description serve to explain the invention and not to limit the invention. Embodiments of the invention are described in detail below with reference to the attached drawing figures, wherein:
FIG. 1 is an X-ray powder diffraction pattern of the porous ceramic membrane materials synthesized in examples 1-5.
Fig. 2 is a scanning electron micrograph of the alumina whisker porous ceramic membrane material prepared in example 1.
Fig. 2(a) is a scanning electron microscope photograph of the porous ceramic membrane perpendicular to the temperature gradient direction, fig. 2(b) is a scanning electron microscope photograph of the porous ceramic membrane parallel to the temperature gradient direction, and fig. 2(c) is a scanning electron microscope photograph of the porous ceramic membrane of the bottom surface separation layer.
Fig. 3 shows the porosity of porous ceramic membrane materials with different sodium alginate solution contents (i.e. the mass of sodium alginate solution (the mass of alumina whisker + the mass of silica sol + the mass of magnesium oxide + the mass of glycerol + the mass of deionized water + the mass of sodium alginate solution)) in the ceramic slurry.
Fig. 4 shows the pore size distribution and nitrogen flux of the porous ceramic membrane synthesized in example 1.
Detailed Description
The invention will be further illustrated with reference to the following specific examples. It should be understood that these examples are for illustrative purposes only and are not intended to limit the scope of the present invention. The experimental procedures, in which specific conditions are not noted in the following examples, are generally carried out according to conventional conditions or according to conditions recommended by the manufacturers.
Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. The reagents or starting materials used in the present invention can be purchased from conventional sources, and unless otherwise specified, the reagents or starting materials used in the present invention can be used in a conventional manner in the art or in accordance with the product specifications. In addition, any methods and materials similar or equivalent to those described herein can be used in the methods of the present invention. The preferred embodiments and materials described herein are intended to be exemplary only.
As introduced in the background art, in the existing sodium alginate system, gel-cured pore-forming is adopted to prepare the porous ceramic material, the production process of ion vertical penetration, ion exchange, solvent exchange and the like is complex and time-consuming, the penetration speed of divalent ions in the sample gelling process and the pore size formed by through holes cannot be accurately controlled, so that the sample flux cannot reach the expected target, and the thickness and the shape of the sample are not controlled ideally.
In order to solve the technical problems, the application provides a method for preparing a high-flux alumina whisker porous ceramic membrane by gel solidification pore-forming, sodium alginate in-situ gel solidification is utilized, ice crystal sizes are regulated and controlled at different directional refrigeration temperatures, after the ice crystals are sublimated and discharged, a directional gradient pore structure (a separation layer and a support layer), a porous alumina ceramic membrane with controllable pore diameter and high porosity can be further obtained, in addition, the alumina whiskers are used as raw materials, the whiskers are mutually lapped to form a hierarchical pore structure, uniform nanopores are distributed on the pore wall, and the membrane flux is further improved and the filtering performance is optimized by combining a gel solidification directional pore-forming process.
In order to make the technical solutions of the present application more clearly understood by those skilled in the art, the technical solutions of the present application will be described in detail below with reference to specific examples and comparative examples.
Example 1
Adding sodium alginate solution according to the following ratio (the mass of the aluminum oxide whisker, the mass of the silica sol, the mass of the magnesium oxide, the mass of the glycerol and the mass of the deionized water): (the weight ratio of the mass of the sodium alginate solution to the mass of the calcium ethylene diamine tetraacetate to the mass of the gluconolactone) is 5:3
Firstly, weighing the following raw materials by weight: 5.24g of alumina whisker, 12.48g of deionized water, 0.393g of silica sol, 0.1572g of magnesium oxide, 0.6051g of glycerol, 1.79g of PVA, 7.92g of sodium alginate solution, 2.43g of calcium ethylene diamine tetracetate solution and 0.3976g of gluconolactone, wherein gamma-Al is prepared by mixing gamma-Al with water at 90 DEG under the condition of water bath2O3Adding crystal whisker, magnesium oxide, glycerol, PVA and silica sol into deionized water, stirring with ultrasonic and magnetic force for 30min, adding sodium alginate solution, stirring for 30min, adding calcium ethylenediamine tetraacetate solution into the slurry, mixing and stirring for 5min, stirringAdding a certain amount of gluconolactone in the stirring process, rapidly stirring to fully mix the gluconolactone in the ceramic slurry to obtain final ceramic slurry, rapidly pouring the ceramic slurry into a mold, placing the mold into a moisture preservation box with a certain temperature and a certain humidity, solidifying for 10h, freezing for 1h at 70 ℃ below zero by using liquid nitrogen as a directional cold source to ensure that ice crystals are completely developed, placing a frozen body in a vacuum drier to sublimate and discharge the frozen ice crystals to obtain a dry porous ceramic blank body with a directional gradient pore structure along the gradient direction of the freezing temperature, firing the blank body at 1500 ℃, and preserving the temperature for 2h to obtain the high-flux alumina whisker porous ceramic membrane material, wherein the porosity of the material is 86.46%, the pore diameter of the material is distributed between 0.25 and 2.25 mu m, and the average pore diameter of the material is 1 mu m.
Example 2
Adding sodium alginate solution according to the following ratio (the mass of the aluminum oxide whisker, the mass of the silica sol, the mass of the magnesium oxide, the mass of the glycerol and the mass of the deionized water): (the weight ratio of the mass of the sodium alginate solution to the mass of the calcium ethylene diamine tetraacetate to the mass of the gluconolactone) is 5:1
Firstly, weighing the following raw materials by weight: 5.24g of alumina whisker, 12.48g of deionized water, 0.393g of silica sol, 0.1572g of magnesium oxide, 0.4513g of glycerol, 1.79g of PVA1, 2.64g of sodium alginate solution, 0.81148g of calcium ethylene diamine tetracetate solution and 0.1325g of gluconolactone, wherein gamma-Al is prepared by mixing gamma-Al with water at 90 DEG C2O3Adding crystal whiskers, magnesium oxide, glycerol, PVA and silica sol into deionized water, stirring for 30min by ultrasonic and magnetic force, adding a sodium alginate solution, continuously stirring for 30min, adding an ethylene diamine tetraacetic acid calcium solution into the slurry, mixing and stirring for 5min, adding a certain amount of gluconolactone during stirring, quickly stirring to fully mix the gluconolactone in the ceramic slurry to obtain final ceramic slurry, quickly pouring the ceramic slurry into a mold, placing the mold into a moisture-preserving box with a certain temperature and humidity of 25 ℃, solidifying for 10h, using liquid nitrogen as a directional cold source, freezing for 1h at-70 ℃ to ensure complete development of ice crystals, placing a frozen body into a vacuum drier to sublimate and discharge the frozen ice crystals to obtain the dried porous ceramic with the directional gradient pore structure along the gradient direction of the freezing temperatureAnd firing the blank at 1500 ℃, and after the heat preservation time is 2 hours, obtaining the high-flux alumina whisker porous ceramic membrane material, wherein the porosity of the material is 78.27%, the pore size distribution is 0.13-1.8 μm, and the average pore size is 0.8 μm.
Example 3
Adding deionized water according to the mass of the aluminum oxide whisker: the materials are mixed according to the weight ratio of (the mass of the aluminum oxide crystal whisker and the mass of the deionized water) 2:5
Firstly, weighing the following raw materials by weight: 5.24g of alumina whisker, 7.86g of deionized water, 0.393g of silica sol, 0.1572g of magnesium oxide, 0.6051g of glycerol, 1.79g of PVA1, 7.92g of sodium alginate solution, 2.43g of calcium ethylene diamine tetraacetate solution and 0.3976g of gluconolactone, and carrying out water bath on gamma-Al at 90 DEG C2O3Adding crystal whiskers, magnesium oxide, glycerol, PVA and silica sol into deionized water, stirring for 30min by ultrasonic and magnetic force, adding a sodium alginate solution, continuously stirring for 30min, adding an ethylene diamine tetraacetic acid calcium solution into the slurry, mixing and stirring for 5min, adding a certain amount of gluconolactone during stirring, quickly stirring to fully mix the gluconolactone in the ceramic slurry to obtain final ceramic slurry, quickly pouring the ceramic slurry into a mold, placing the mold into a moisture-preserving box with a certain humidity and a temperature of 25 ℃, solidifying for 10h, using liquid nitrogen as a directional cold source, freezing for 1h at 70 ℃ to ensure complete development of ice crystals, placing a frozen body into a vacuum drier to sublimate the frozen ice crystals, obtaining a dried porous ceramic blank body with a directional gradient pore structure along the gradient direction of the freezing temperature, firing the blank body at the temperature of 1500 ℃, preserving the temperature for 2h to obtain a high-flux alumina crystal whisker porous ceramic membrane material, the porosity of the material is 82.57%, the pore size distribution is between 0.16 and 1.88 μm, and the average pore size is 0.87 μm.
Example 4
Adding sodium alginate solution according to the following ratio (the mass of the aluminum oxide whisker, the mass of the silica sol, the mass of the magnesium oxide, the mass of the glycerol and the mass of the deionized water): (the mass of the sodium alginate solution, the mass of the calcium ethylene diamine tetraacetate and the mass of the gluconolactone) is mixed according to the weight ratio of 5:3, and the refrigeration temperature is-90 ℃.
Firstly, weighing the following raw materials by weight: 5.24g of alumina whisker, 12.48g of deionized water, 0.393g of silica sol, 0.1572g of magnesium oxide, 0.6051g of glycerol, 1.79g of PVA1, 7.92g of sodium alginate solution, 2.43g of calcium ethylene diamine tetraacetate solution and 0.3976g of gluconolactone, and reacting the gamma-Al with water at 90 DEG C2O3Adding crystal whiskers, magnesium oxide, glycerol, PVA and silica sol into deionized water, stirring for 30min by ultrasonic and magnetic force, adding a sodium alginate solution, continuously stirring for 30min, adding an ethylene diamine tetraacetic acid calcium solution into the slurry, mixing and stirring for 5min, adding a certain amount of gluconolactone during stirring, quickly stirring to fully mix the gluconolactone in the ceramic slurry to obtain final ceramic slurry, quickly pouring the ceramic slurry into a mold, placing the mold into a moisture-preserving box with a certain humidity and a temperature of 25 ℃, solidifying for 10h, using liquid nitrogen as a directional cold source, freezing for 1h at 90 ℃ to ensure complete development of ice crystals, placing a frozen body into a vacuum drier to sublimate the frozen ice crystals, obtaining a dried porous ceramic blank body with a directional gradient pore structure along the gradient direction of the freezing temperature, firing the blank body at the temperature of 1500 ℃, preserving the temperature for 2h to obtain a high-flux alumina crystal whisker porous ceramic membrane material, the porosity of the material is 86.37%, the pore diameter is reduced compared with the material of the embodiment 1, the pore diameter distribution is between 0.13 and 1.76 mu m, and the average pore diameter is 0.78 mu m.
Example 5
Adding sodium alginate solution according to the following ratio (the mass of the aluminum oxide whisker, the mass of the silica sol, the mass of the magnesium oxide, the mass of the glycerol and the mass of the deionized water): (the mass of the sodium alginate solution, the mass of the calcium ethylene diamine tetraacetate and the mass of the gluconolactone) is mixed according to the weight ratio of 5:3, and the sample is sintered at the temperature of 1550 DEG C
Firstly, weighing the following raw materials by weight: 5.24g of alumina whisker, 12.48g of deionized water, 0.393g of silica sol, 0.1572g of magnesium oxide, 0.6051g of glycerol, 1.79g of PVA1, 7.92g of sodium alginate solution, 2.43g of calcium ethylene diamine tetraacetate solution and 0.3976g of gluconolactone, and reacting the gamma-Al with water at 90 DEG C2O3Whisker, magnesium oxide, glycerin, PVA and silica solAdding glue into deionized water, stirring for 30min by ultrasonic and magnetic force, adding sodium alginate solution, stirring for 30min, adding calcium ethylenediamine tetraacetate solution into the slurry, mixing and stirring for 5min, adding a certain amount of gluconolactone during stirring, stirring rapidly to mix thoroughly in the ceramic slurry to obtain final ceramic slurry, pouring the ceramic slurry into a mold rapidly, placing into a moisture-preserving box with a certain humidity and a certain temperature of 25 ℃, solidifying for 10h, using liquid nitrogen as a directional cold source, freezing for 1h at-70 ℃ to ensure complete development of ice crystals, placing the frozen body in a vacuum drier to discharge and sublimate the frozen ice crystals to obtain a dry porous ceramic blank body with a directional gradient pore structure along the gradient direction of freezing temperature, firing the blank body at 1550 ℃ for 2h to obtain a high-flux alumina whisker porous ceramic membrane material, the porosity of the material is 82.65%, the pore size distribution is between 0.22 and 1.76 mu m, and the average pore size is 0.83 mu m.
From the X-ray powder diffraction analysis of FIG. 1, the main crystal phases of the material are alumina and magnesium aluminate spinel (MgAl)2O4) As can be seen from fig. 2, in the alumina whisker porous ceramic membrane material, the sample has a relatively uniform directional gradient pore structure (a separation layer and a support layer), and whiskers on the pore wall are mutually overlapped to form a porous nanostructure, the pore diameter is about 20 μm, so that the prepared porous ceramic membrane has relatively high flux. As can be seen from FIG. 3, the alumina whisker porous ceramic membrane has higher porosity, and the porosity is increased along with the increase of the content of the sodium alginate solution. As can be seen from fig. 4, the pore size distribution is relatively uniform, and the nitrogen flux is relatively high, so that the filtration precision and the filtration efficiency are relatively high.
To summarize: example 1 and example 2 compare, the content of the sodium alginate solution is different, and the influence of the sodium alginate solution on the porosity and the pore diameter is as follows: in the content range of the invention, the higher the content of the sodium alginate solution is, the higher the porosity is, and the larger the pore diameter is; comparison of example 1 and example 3, the solids content (mass of alumina whiskers + mass of magnesia + silica in silica sol) is different, the effect of the solids content on the porosity and pore size is: in the range of solid content of the invention, the higher the solid content is, the lower the porosity is, and the smaller the pore diameter is; comparison of example 1 and example 4, the refrigeration temperatures were different and the effect of the refrigeration temperatures on the pores was: the lower the refrigeration temperature is, the smaller the pore diameter is; in comparison between example 1 and example 5, the firing temperature was different, and the effect of the firing temperature on the porosity was: the higher the firing temperature, the lower the porosity; the influence of the firing temperature on the compressive strength is as follows: the higher the firing temperature, the higher the compressive strength.
Although the present invention has been described in detail with reference to the foregoing embodiments, it will be apparent to those skilled in the art that changes may be made in the embodiments and/or equivalents thereof without departing from the spirit and scope of the invention. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims (10)

1. A method for preparing a porous ceramic membrane material, which comprises the following steps: under the water bath environment, adding a sodium alginate solution in the process of preparing the raw material powder into ceramic slurry, mixing with an ethylene diamine tetraacetic acid calcium solution and gluconolactone, carrying out directional freezing hole control after in-situ gel solidification, and sintering to obtain the porous ceramic membrane material.
2. The method of claim 1, wherein the calcium ethylenediaminetetraacetate solution is prepared from disodium ethylenediaminetetraacetate and calcium carbonate;
preferably, the water bath temperature is 80-90 ℃;
preferably, the in situ gel curing comprises: the gluconolactone provides hydrogen ions, calcium ethylene diamine tetraacetic acid combines the hydrogen ions to release calcium ions, and sodium alginate and the calcium ions are chelated in situ to form a network chain structure.
Preferably, the directional freeze control orifice comprises: the water is crystallized by regulating the temperature of the directional cold source, the size of the ice crystal is regulated, after the ice crystal is completely grown by freezing, the frozen ice crystal is sublimated and discharged by vacuum freeze drying under the low-pressure vacuum environment, and thus, a directional porous structure is formed.
3. The preparation method according to claim 1 or 2, characterized in that under the water bath condition, the alumina whisker is used as a raw material, a sodium alginate solution is added, and is mixed with an ethylene diamine tetraacetic acid calcium solution and gluconolactone to form ceramic slurry, directional freezing and pore control are carried out after in-situ gel solidification, and the alumina whisker porous ceramic membrane material is prepared by sintering.
4. The preparation method according to claim 3, wherein the weight ratio of the calcium ethylenediaminetetraacetate solution to the gluconolactone to the sodium alginate solution is (2-10): 0-3): 10-25, preferably (2-10): 0.2-3): 10-25, more preferably 6:1: 20;
preferably, the curing time is 4-24 h;
preferably, the freezing temperature is-196 ℃ to-20 ℃;
preferably, the freezing time is 0.5h-10 h;
preferably, the sintering conditions are: the sintering temperature is 1300-1600 ℃, and the heat preservation time is 2-3 hours.
5. The method according to claim 3, wherein the ceramic slurry further contains magnesium oxide, glycerin, PVA, and silica sol;
preferably, the preparation method of the ceramic slurry comprises the following steps: uniformly mixing aluminum oxide whiskers, magnesium oxide, glycerol, PVA, silica sol, deionized water and a sodium alginate solution, then adding an ethylene diamine tetraacetic acid calcium solution, and adding glucolactone in the stirring process to fully mix the materials to form uniform ceramic slurry;
preferably, the mass ratio of the alumina whisker, the magnesium oxide, the silica sol, the PVA, the glycerol, the deionized water and the sodium alginate solution is (100- & lt 120- & gt): (1-6): (3-16): (0-71): (3-15): (157-419): (26-211);
preferably, the mass ratio of the alumina whisker, the magnesium oxide, the silica sol, the PVA, the glycerol, the deionized water and the sodium alginate solution is (100- & lt 120- & gt): (1-6): (3-16): (1-71): (3-15): (157-419): (26-211).
6. The method according to claim 3, wherein the alumina whiskers are γ -Al2O3Whisker;
preferably, the preparation of the alumina whisker comprises: dissolving aluminum nitrate in deionized water to obtain an aluminum nitrate solution, adding urea and polyethylene glycol, uniformly mixing, pouring into a reaction kettle for hydrothermal treatment to obtain aluminum ammonium carbonate whiskers, dispersing the aluminum ammonium carbonate whiskers, and sintering to obtain gamma-Al2O3Whisker;
preferably, during the preparation process of the aluminum oxide whisker, the concentration of the aluminum nitrate solution is 1.07-1.5 mol/L;
preferably, in the preparation process of the aluminum oxide whisker, the mass ratio of polyethylene glycol to aluminum nitrate is (0-1): (1-5); preferably (0.02-1): (1-5), more preferably 1: 1;
preferably, during the preparation process of the alumina whisker, the pH value of the urea adjusting solution is 9-10;
preferably, in the preparation process of the alumina whisker, the hydrothermal temperature is 120-200 ℃, and the hydrothermal time is 12-48 h;
preferably, the aluminum carbonate ammonia crystal whisker is dispersed in a manner selected from one or more of alcohol washing, ultrasonic stirring and heating stirring during the preparation process of the aluminum oxide crystal whisker; preferably, alcohol washing, ultrasonic stirring and heating stirring are carried out;
preferably, during the preparation process of the aluminum oxide whisker, the aluminum ammonium carbonate whisker is dispersed for 30-120 min;
preferably, the sintering temperature in the preparation process of the alumina whisker is 600-800 ℃.
7. The preparation method of claim 3, wherein the sodium alginate solution is deionized water solution of sodium alginate, and the concentration of the deionized water solution is 2-5 mol/L;
preferably, the preparation method of the sodium alginate solution comprises the following steps: adding sodium alginate powder into deionized water at 80-90 ℃, and stirring for 0.5-2 hours;
preferably, the calcium ethylene diamine tetraacetate solution is prepared by adding disodium ethylene diamine tetraacetate and calcium carbonate into deionized water for mixing;
preferably, the mass ratio of the disodium ethylene diamine tetraacetate, the calcium carbonate and the deionized water is (30-50): (1-6): (1-2); preferably 50:4: 1.
8. The preparation method according to claim 3, wherein the preparation method of the alumina whisker porous ceramic membrane material comprises the following steps:
adding urea into an aluminum nitrate solution to adjust the pH, then adding polyethylene glycol, uniformly mixing, performing hydrothermal reaction in a reaction kettle to obtain ammonium aluminum carbonate whiskers, dispersing the ammonium aluminum carbonate whiskers, and sintering to obtain gamma-Al2O3Whisker;
under the condition of water bath, gamma-Al is added2O3Adding the crystal whisker, magnesium oxide, glycerol, PVA and silica sol into deionized water, adding a calcium ethylene diamine tetraacetic acid solution, and adding glucolactone in the stirring process to fully mix the materials to form uniform ceramic slurry;
pouring the ceramic slurry into a mold rapidly, carrying out in-situ gel solidification in a moisture preserving box, wherein, gluconolactone provides hydrogen ions, calcium ethylene diamine tetracetate combines the hydrogen ions to release calcium ions, triggering sodium alginate and the calcium ions to chelate in situ to form a network chain structure, directionally freezing and controlling pores after solidification, comprising utilizing liquid nitrogen as a directional cold source, utilizing different refrigeration temperatures to regulate and control the size of ice crystals, freezing to ensure the complete development of the ice crystals, carrying out vacuum freeze drying, comprising placing a frozen body in a low-pressure environment to sublimate and discharge the frozen ice crystals, obtaining a dry porous ceramic blank body with a directional gradient pore structure along the gradient direction of the freezing temperature, and sintering to obtain the alumina whisker porous ceramic membrane material.
9. A porous ceramic membrane material prepared by the preparation method of any one of claims 1 to 8; preferably, the porous ceramic membrane material is an alumina whisker porous ceramic membrane material;
preferably, the pore size distribution of the alumina whisker porous ceramic membrane material is 0.13-2.25 μm, the average pore size is 0.78-1 μm, the porosity is higher than 80%, and the nitrogen flux is not less than 1.52 x 106L/m2·h·bar。
10. The porous ceramic membrane material of claim 9, for use in oil-water separation, industrial water treatment, industrial circulating cooling water purification, and process water treatment.
CN201911350627.9A 2019-12-24 2019-12-24 Porous ceramic membrane material and preparation method and application thereof Withdrawn CN110981529A (en)

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112408763A (en) * 2020-11-23 2021-02-26 徐州创合新材料科技有限公司 Toughened glass heat-insulating coating and preparation method thereof
CN114350162A (en) * 2021-12-23 2022-04-15 之江实验室 Gradient pore structure silk fibroin film and preparation method thereof

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112408763A (en) * 2020-11-23 2021-02-26 徐州创合新材料科技有限公司 Toughened glass heat-insulating coating and preparation method thereof
CN112408763B (en) * 2020-11-23 2021-11-05 徐州创合新材料科技有限公司 Toughened glass heat-insulating coating and preparation method thereof
CN114350162A (en) * 2021-12-23 2022-04-15 之江实验室 Gradient pore structure silk fibroin film and preparation method thereof

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