CN115180970A - Composition for producing fly ash-based porous ceramic, fly ash-based porous ceramic and preparation method and application thereof - Google Patents

Composition for producing fly ash-based porous ceramic, fly ash-based porous ceramic and preparation method and application thereof Download PDF

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CN115180970A
CN115180970A CN202110358796.8A CN202110358796A CN115180970A CN 115180970 A CN115180970 A CN 115180970A CN 202110358796 A CN202110358796 A CN 202110358796A CN 115180970 A CN115180970 A CN 115180970A
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fly ash
metal oxide
porous ceramic
based porous
content
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CN115180970B (en
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马宁
董阳
卓锦德
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China Energy Investment Corp Ltd
National Institute of Clean and Low Carbon Energy
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China Energy Investment Corp Ltd
National Institute of Clean and Low Carbon Energy
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Abstract

The invention relates to the technical field of ceramics, in particular to a composition for producing fly ash-based porous ceramic, fly ash-based porous ceramic and a preparation method and application thereof. When the fly ash and the auxiliary materials (the organic forming agent, the dispersing agent, the IIIA group metal oxide, the alkaline earth metal oxide, the IVB group metal oxide, the IB group metal oxide and the inorganic plasticizer) with specific contents are adopted, the fly ash and the auxiliary materials do not need to be ground, ball-milled and other crushing processes in the process of preparing the fly ash-based porous ceramic, so that the prepared fly ash-based porous ceramic keeps the natural morphology of the fly ash, and the solid particles of the fly ash-based porous ceramic comprise at least 50% of spherical morphology particles, so that the fly ash-based porous ceramic has high porosity, high bending strength and good acid-base corrosion resistance.

Description

Composition for producing fly ash-based porous ceramic, fly ash-based porous ceramic and preparation method and application thereof
Technical Field
The invention relates to the technical field of ceramics, in particular to a composition for producing fly ash porous ceramics, fly ash-based porous ceramics, and a preparation method and application thereof.
Background
The fly ash is industrial waste with abundant reserves, low price and easy obtainment, and the main component is SiO 2 And Al 2 O 3 The content of the two components reaches more than 70 percent, which is similar to the clay component in the raw material of the traditional ceramics. In addition, the fly ash has a large number of micropores and a high specific surface area. The utilization of the industrial waste can not only reduce the environmental pollution, but also develop and produce the ceramics with low cost and high added value.
CN103204673A discloses a fly ash sintered material for water treatment, a fly ash membrane and a filler are inorganic microporous materials formed by sintering fly ash, and the method comprises the following steps: (1) fly ash and the ingredients thereof by weight ratio: 60-70 parts of fly ash, 20-30 parts of clay and 10 parts of carbon particles are mixed and ground to 80-200 meshes, water is added for mixing, wetting and mixing uniformly, aging and molding are carried out, the shape can be made into a tubular shape, a porous shape and a flat shape, the mixture is naturally dried, sintering is carried out, the sintering temperature is controlled to be 1200-1700 ℃, leaves are activated in an activation chamber for 30min and taken out, and the aperture of the leaves is 0.1-90.0 mu m. However, in order to obtain the physical and chemical properties of the inorganic ceramic membrane, clay and carbon powder are additionally added into the ingredients, the fly ash and the ingredients thereof are also required to be ground, the using amount of the fly ash is only 60-70, and the fly ash is not fully utilized.
CN108178658A discloses a method for preparing aluminum titanate mullite composite porous ceramic by using fly ash as a raw material, which comprises the following steps: 1) Mixing a mixture consisting of 44-47 parts of fly ash, 44-46 parts of pseudo-boehmite and 7-12 parts of titanium oxide with deionized water; 2) Drying the mixed slurry obtained in the step 1) to obtain raw material powder; 3) Stirring starch, raw material powder, PVA and deionized water to obtain a uniform suspension, pouring the suspension into a mould, and carrying out curing, demoulding and drying; 4) And (4) sintering the sample dried in the step 3) to obtain the aluminum titanate mullite composite porous ceramic material. However, in order to prepare the stable aluminum titanate mullite composite porous ceramic material, the method needs to limit the fly ash to contain a certain amount of ferric oxide, and the use amount of the fly ash is only 44-47, so that the fly ash is not fully utilized; in addition, the process is complex and is not convenient for industrial production.
CN109126482A discloses a preparation method of a fly ash-alumina double-layer composite microfiltration membrane, which comprises the steps of firstly preparing a high-performance fly ash carrier by adjusting the sintering temperature of the fly ash carrier and the addition amount of organic matters, and providing good mechanical strength for a subsequent ceramic membrane; secondly, preparing stable membrane making liquid from high-purity alumina powder, a dispersing agent and a thickening agent, coating the stable membrane making liquid on a fly ash carrier, and preparing the double-layer fly ash-alumina double-layer composite membrane through a heat treatment process. The method does not relate to how to improve the acid and alkali resistance of the fly ash-alumina double-layer composite microfiltration membrane.
Therefore, in the prior art, the fly ash is used as a raw material to prepare the ceramic membrane, the utilization rate of the fly ash is low, the process is complex, and the prepared fly ash ceramic (membrane) has poor performance, particularly acid and alkali resistance. In addition, in the prior art, alumina is basically used for preparing the medium-pore thin-wall ceramic, the fly ash is difficult to be used for preparing the hollow thin-wall ceramic, the problems of cracking, low porosity, low strength and easy deformation are difficult to solve, and meanwhile, the acid and alkali resistance hardly reaches the use requirement and the standard requirement of honeycomb hollow plate ceramic membrane (T/CCIA 0003-2018).
Disclosure of Invention
The invention aims to solve the problems that in the prior art, porous ceramics prepared by adopting fly ash have poor acid and alkali resistance, low strength, easy cracking of wet blank sintering, low porosity, need to add pore-forming agent to improve the porosity and the like, and provides a composition for producing fly ash-based porous ceramics, a fly ash-based porous ceramic, a preparation method and application thereof. The composition takes the fly ash as a main raw material, and can obviously improve the bending strength, the porosity and the acid and alkali corrosion resistance of the fly ash-based porous ceramic.
In order to achieve the above object, a first aspect of the present invention provides a composition for producing a fly ash-based porous ceramic, the composition comprising: the composite material comprises fly ash, an organic forming agent, a dispersing agent, IIIA group metal oxide, alkaline earth metal oxide, IVB group metal oxide, IB group metal oxide and an inorganic plasticizer;
wherein, based on the total weight of the composition, the content of the fly ash is 72-89.5wt%, the content of the organic forming agent is 4-9wt%, the content of the dispersant is 0.2-1wt%, the content of the IIIA group metal oxide is 3-8wt%, the content of the alkaline earth metal oxide is 0.1-1wt%, the content of the IVB group metal oxide is 0.1-1.5wt%, the content of the IB group metal oxide is 0.1-1.5wt%, and the content of the inorganic plasticizer is 3-6wt%.
In a second aspect, the present invention provides a method for preparing a fly ash-based porous ceramic, comprising the steps of:
(1) Mixing the composition provided by the first aspect with water, and then molding;
(2) And sintering the formed blank to obtain the fly ash-based porous ceramic.
In a third aspect, the invention provides a fly ash-based porous ceramic prepared by the method provided in the second aspect.
Preferably, the volume weight of the fly ash-based porous ceramic is 1.2-2g/cm 3 The average pore diameter is 0.5-10 μm, the porosity is 40-60%, the bending strength is 30-100MPa, the acid corrosion mass loss rate is less than or equal to 0.3%, the alkali corrosion mass loss rate is less than or equal to 0.5%, the acid corrosion bending strength loss rate is less than or equal to 10%, and the alkali corrosion bending strength loss rate is less than or equal to 10%.
The invention provides the application of the fly ash-based porous ceramic provided by the third aspect in building, sound absorption, water treatment and flue gas filtration.
Through the technical scheme, when the fly ash with specific content and the auxiliary materials (the organic forming agent, the dispersing agent, the IIIA group metal oxide, the alkaline earth metal oxide, the IVB group metal oxide, the IB group metal oxide and the inorganic plasticizer) with specific content are adopted, particularly the fly ash with specific composition content is adopted, and the fly ash and the auxiliary materials are not required to be ground, ball-milled and other crushing processes in the process of preparing the fly ash-based porous ceramic, so that the prepared fly ash-based porous ceramic keeps the natural morphology of the fly ash under the conditions of reducing the process complexity and improving the fly ash utilization rate (no additional pore-forming agent is required to be added), and solid particles of the fly ash-based porous ceramic contain at least 50% of spherical morphology particles, so that the fly ash-based porous ceramic has higher porosity and bending strength and better acid and alkali corrosion resistance.
Additional features and advantages of the invention will be set forth in the detailed description which follows.
Drawings
FIG. 1 is a surface microscopic SEM image of a fly ash-based porous ceramic A1 prepared in example 1.
Detailed Description
The endpoints of the ranges and any values disclosed herein are not limited to the precise range or value, and such ranges or values should be understood to encompass values close to those ranges or values. For numerical ranges, each range between its endpoints and individual point values, and each individual point value can be combined with each other to give one or more new numerical ranges, and such numerical ranges should be construed as specifically disclosed herein.
In the present invention, unless explicitly stated otherwise, "first", "second", and "third" do not denote any order or importance, nor do they limit the respective materials or operations, but rather distinguish the respective materials or operations, for example, "first", "second", and "third" in "first mixing", "second mixing", and "third mixing" are merely for distinguishing to indicate that they are not the same mixing.
The present invention provides in a first aspect a composition for producing a fly ash-based porous ceramic, the composition comprising: the composite material comprises fly ash, an organic forming agent, a dispersing agent, IIIA group metal oxide, alkaline earth metal oxide, IVB group metal oxide, IB group metal oxide and an inorganic plasticizer;
wherein, based on the total weight of the composition, the content of the fly ash is 72-89.5wt%, the content of the organic forming agent is 4-9wt%, the content of the dispersant is 0.2-1wt%, the content of the IIIA group metal oxide is 3-8wt%, the content of the alkaline earth metal oxide is 0.1-1wt%, the content of the IVB group metal oxide is 0.1-1.5wt%, the content of the IB group metal oxide is 0.1-1.5wt%, and the content of the inorganic plasticizer is 3-6wt%.
The inventor of the invention researches and finds that: the main components of the fly ash are silicon oxide and aluminum oxide, so compared with an aluminum oxide ceramic membrane, the acid and alkali resistance and the strength of the fly ash hardly reach the level of aluminum oxide porous ceramic, therefore, the inventor leads the fly ash with specific content and auxiliary materials (organic forming agent, dispersing agent, IIIA group metal oxide, alkaline earth metal oxide, IVB group metal oxide, IB group metal oxide and inorganic plasticizer) with specific content to form an aluminum-rich mullite crystal phase under the sintering condition through the interaction of the fly ash, the IIIA group metal oxide, the alkaline earth metal oxide, IVB group metal oxide, IB group metal oxide and the inorganic plasticizer, thereby obviously increasing the bending strength of the fly ash-based porous ceramic and the bending strength after acid and alkali corrosion resistance, leading the bending strength loss rate of acid corrosion to be less than or equal to 10 percent and the bending strength loss rate of alkali corrosion to be less than or equal to 10 percent.
In the present invention, when, without particular description, in the fly ash-based porous ceramic: and when R = alumina content X100%/(alumina content + silica content) > 0.72, the coal ash-based porous ceramic has an aluminum-rich mullite crystal phase, wherein the alumina content and the silica content are both obtained by EDS (electron-dispersive spectroscopy) energy scattering X-ray spectroscopy.
In the present invention, the content of each component in the composition is the amount of each component charged or used, unless otherwise specified.
According to the invention, preferably, the content of the fly ash is 78-88wt%, the content of the organic forming agent is 3-6wt%, the content of the dispersant is 0.5-1wt%, the content of the IIIA group metal oxide is 3-6wt%, the content of the alkaline earth metal oxide is 0.5-1wt%, the content of the IVB group metal oxide is 0.5-1wt%, the content of the IB group metal oxide is 0.5-1wt%, and the content of the inorganic plasticizer is 4-6wt% based on the total weight of the composition.
According to the invention, the fly ash preferably contains 60 to 90%, preferably 65 to 85%, of spherical-shaped particles and 10 to 40%, preferably 15 to 35%, of non-spherical-shaped particles. The sum of the content of the spherical particles and the content of the non-spherical particles is 100%, and the content of the spherical particles is calculated by number percentage.
In the invention, the spherical particles refer to solid particles with the sphericity of more than 0.7 without special condition; the non-spherical morphology particles refer to solid particles with the sphericity below 0.7.
In the invention, the content parameters of the spherical particles in the fly ash are measured by an electron scanning microscope, and specifically comprise the following steps: selecting 5 SEM pictures (magnification is 1000 times) for each fly ash sample, selecting an area of 300 multiplied by 300 mu m for each picture, and measuring the content of spherical morphology particles with the sphericity of more than 0.7 in the area in each picture, wherein the content is respectively marked as m 1 、m 2 、m 3 、m 4 And m 5 Wherein, the content of the spherical particles refers to the percentage of the number of particles with sphericity of more than 0.7 in the determination area to the total number of particles, and then the content of the spherical particles in the fly ash is = (m) 1 +m 2 +m 3 +m 4 +m 5 )/5. The sphericity is measured by a microscope, and the sphericity = (4 × pi × projection area)/(projection perimeter × projection perimeter).
According to the invention, the fly ash preferably has a particle size of 1 to 100 μm, preferably 10 to 30 μm. Wherein the particle size parameter of the fly ash is measured by a Malvern laser particle size analyzer MS 2000.
In the present invention, the particle size refers to the maximum straight-line distance between any two different points on the particle, without specific description. For example, when the particles are spherical, the particle size refers to their diameter.
In the present invention, the composition does not need to add pore-forming agent, such as common carbon black, starch-based powder, calcium carbonate, polystyrene particles. Preferably, no additional pore-forming agent is included in the composition.
According to a preferred embodiment of the present invention, the composition consists of fly ash, an organic forming agent, a dispersant, a group IIIA metal oxide, an alkaline earth metal oxide, a group IVB metal oxide, a group IB metal oxide and an inorganic plasticizer; wherein, the content of the fly ash is 72-89.5wt%, preferably 78-88wt% based on the total weight of the composition; the content of the organic forming agent is 4-9wt%, preferably 3-6wt%; the content of the dispersant is 0.2-1wt%, preferably 0.5-1wt%; the content of the IIIA group metal oxide is 3-8wt%, preferably 3-6wt%; the content of the alkaline earth metal oxide is 0.1-1wt%, preferably 0.5-1wt%; the content of the group IVB metal oxide is 0.1 to 1.5wt%, preferably 0.5 to 1wt%; the content of the group IB metal oxide is 0.1-1.5wt%, preferably 0.5-1wt%; the content of the inorganic plasticizer is 3 to 6wt%, preferably 4 to 6wt%.
According to the invention, the fly ash preferably contains a component M selected from TiO 2 At least one of CaO and MgO, and the content of the component M is 2-5wt%, preferably 3-4wt%, based on the total weight of the fly ash.
In some embodiments of the invention, the fly ash containing component M may be selected from TiO 2 One, two or three of CaO and MgO, and the content of the component M is 2-5wt%, preferably 3-4wt% based on the total weight of the fly ash。
According to a preferred embodiment of the invention, component M of the fly ash may be selected from TiO 2 At least two of CaO and MgO, which may be TiO 2 And any combination of CaO and MgO, preferably TiO 2 And CaO, and TiO 2 And CaO in a weight ratio of 1: 0.6-2, and further preferably, tiO 2 And CaO in a weight ratio of 1: 1-1.5. In particular, when TiO 2 When the weight ratio of the fly ash-based porous ceramic to CaO is 1: 1.5-1, the porosity, the bending strength and the acid and alkali resistance of the prepared fly ash-based porous ceramic can be further improved.
Specifically, the fly ash can also contain Al 2 O 3 And SiO 2 . Preferably, based on the total weight of the fly ash, al in the fly ash is used as the reference 2 O 3 In an amount of from 35 to 70% by weight, preferably from 40 to 60% by weight; siO 2 2 The content of (B) is 15 to 60wt%, preferably 35 to 50wt%. The inventor of the invention finds that Al is adopted in research 2 O 3 High fly ash content, especially Al 2 O 3 When the content of (b) is in the range of 40 to 60wt%, the porosity, bending strength and acid and alkali resistance of the fly ash-based porous ceramic obtained can be further improved.
In the invention, tiO in the fly ash 2 、CaO、MgO、Al 2 O 3 And SiO 2 The contents of (b) are each measured by an X-ray fluorescence spectroscopic analysis method.
In the present invention, the fly ash contains, in addition to the above-mentioned components, other inevitable impurities such as K 2 O、Na 2 O and P 2 O 5 Etc., which are not discussed herein in greater detail.
In the present invention, the kind and source of the organic molding agent are widely selected, and in the present invention, the organic molding agent is an organic compound having a viscosity in the range of 3000 to 200000mPa · s. Preferably, the organic forming agent is selected from at least one of methylcellulose, carboxymethylcellulose, hydroxypropylmethylcellulose, polyvinyl alcohol and polyanionic cellulose, more preferably methylcellulose and/or carboxymethylcellulose. The viscosity of the methyl cellulose is 5000-150000 mPas, the viscosity of the carboxymethyl cellulose is 5000-150000 mPas, and the polyvinyl alcohol can be polyvinyl alcohol with the trade name of PVA-1799 and/or PVA-1788. In the invention, the performance index of the polyanionic cellulose preferably meets the requirement of GBT 35928-2018 polyanionic cellulose.
In the present invention, the kind of the dispersant may be selected widely as long as the average molecular weight of the dispersant is 2000 to 20000 g/mol. Preferably, the dispersant is selected from at least one of ammonium polyacrylate, sodium polyacrylate, polyacrylic acid, citric acid and sodium citrate, more preferably ammonium polyacrylate and/or sodium polyacrylate. In the present invention, the source of the dispersant is not particularly limited, and the dispersant may be commercially available or may be prepared by a conventional technique.
In some embodiments of the invention, preferably, the group IIIA metal oxide is aluminum oxide; further preferably, the particle size of the alumina is 0.1 to 5 μm, preferably 0.3 to 1 μm.
In some embodiments of the invention, preferably, the group IVB metal oxide is titanium oxide; further preferably, the titanium oxide has a particle size of 0.1 to 10 μm, preferably 0.5 to 4 μm.
In some embodiments of the invention, preferably, the group IB metal oxide is copper oxide; further preferably, the particle size of the copper oxide is 0.1 to 8 μm, preferably 0.5 to 3 μm.
In the invention, the alumina, the titanium oxide and the copper oxide which meet the particle size range can be combined with the fly ash, the alkaline earth metal oxide and the inorganic plasticizer in the formula at a certain sintering temperature to form an aluminum-rich mullite crystal phase, which is different from a mullite crystal phase formed by conventional fly ash ceramics, and the aluminum-rich mullite crystal phase obviously increases the acid-base corrosion resistance and the bending strength of the fly ash-based porous ceramics, and simultaneously ensures the porosity and the porosity performance.
According to the invention, preferably, the alkaline earth metal oxide is selected from magnesium oxide and/or calcium oxide.
In the present invention, the selection range of the kind of the inorganic plasticizer is wide. Preferably, the inorganic plasticizer is selected from at least one of kaolin, bentonite, and clay. In the present invention, the source of the inorganic plasticizer is not particularly limited, and the inorganic plasticizer may be commercially available or may be prepared by a conventional technique.
According to a particularly preferred embodiment of the present invention, a composition for producing a fly ash-based porous ceramic, which consists of fly ash, an organic forming agent, a dispersant, alumina, an alkaline earth metal oxide, titanium oxide, copper oxide and an inorganic plasticizer;
wherein, based on the total weight of the composition, the content of the fly ash is 78-88wt%, the content of the organic forming agent is 3-6wt%, the content of the dispersant is 0.5-1wt%, the content of the aluminum oxide is 3-6wt%, the content of the alkaline earth metal oxide is 0.5-1wt%, the content of the titanium oxide is 0.5-1wt%, the content of the copper oxide is 0.5-1wt%, and the content of the inorganic plasticizer is 4-6wt%;
wherein the fly ash contains a component M, and the component M is selected from TiO 2 At least one of CaO and MgO, and the content of the component M is 3-4wt% based on the total weight of the fly ash.
In a second aspect, the present invention provides a method for preparing a fly ash-based porous ceramic, comprising the steps of:
(1) Mixing the composition provided by the first aspect with water, and then molding;
(2) And sintering the formed blank to obtain the fly ash-based porous ceramic.
In the present invention, the mixing in the step (1) is not particularly limited as long as each component in the composition is uniformly mixed with water. Preferably, the mixing in step (1) comprises:
1) Carrying out first mixing on the fly ash and an organic forming agent to obtain a mixture;
2) Secondly mixing the dispersant, IIIA group metal oxide, alkaline earth metal oxide, IVB group metal oxide, IB group metal oxide and inorganic plasticizer with water to obtain suspension;
3) And thirdly mixing the mixture and the suspension to obtain a mixture.
In the invention, the preferable mixing mode in the step (1) enables the IIIA group metal oxide, the alkaline earth metal oxide, the IVB group metal oxide, the IB group metal oxide and the inorganic plasticizer to be uniformly dispersed around the fly ash particles, and an aluminum-rich mullite crystal phase is formed in the sintering process, thereby ensuring the performance of the fly ash.
In the present invention, the kinds and contents (by weight) of the components in the composition are defined as above, and the description thereof is omitted.
According to the invention, the weight ratio of the fly ash to the water is preferably 1: 0.2-0.6, preferably 1: 0.35-0.55.
According to the present invention, in particular, the method may further include: before the forming, the composition and water are mixed to obtain a mixture, the mixture is subjected to staling and mud refining in sequence, and then the forming is carried out.
In the present invention, the aging refers to a process of placing a mixture obtained by mixing the composition and water in a container for a period of time to disperse the component substances in the mixture more uniformly, and in the present invention, the aging condition is not specifically limited, and the aging condition may include: the temperature is 10-40 ℃, and the time is 24-72h.
In the invention, the condition of the pug refining is not particularly limited, the pug refining can be manual pug refining or mechanical vacuum pug refining, and the pug refining aims to uniformly mix aged materials and ensure that no air exists in the aged materials.
In the present invention, the molding may be a conventional molding method, and may be press molding or extrusion molding.
In the present invention, preferably, the shape of the blank obtained by the molding is tubular or plate-like, and further preferably, the shape of the blank is tubular or plate-like with at least one channel.
According to the invention, preferably, the channel is arranged coaxially with the blank. When the number of channels is more than 2, it is preferable that the different channels are parallel to each other.
In the present invention, it is preferable that the tubular shape has an outer diameter of 5 to 60mm and the number of passages is 1 to 100.
In the present invention, preferably, the width of the plate is 60 to 1000mm, the thickness is 2 to 10mm, the wall thickness is 0.5 to 5mm, and the number of channels is 6 to 200.
In the present invention, the plate-shaped wall thickness means a minimum straight distance of an edge of the plate-shaped passage from an upper surface or a lower surface of the plate-shaped passage, which is a surface parallel to a width direction of the plate-shaped passage.
In the present invention, the shape of the channel of the plate-shaped or tubular blank is not particularly limited, and may be changed according to the specific shape of the die, for example, the cross section of the channel may be circular, triangular, square, etc. According to one embodiment of the invention, the cross-sectional shape of the channel is circular, preferably the diameter of the circle is 0.2-40mm.
The body of the fly ash-based porous ceramic prepared by the composition can have a larger size and is not easy to bend.
According to a preferred embodiment of the invention, the tubular outer diameter is preferably 5-60mm; the plate shape is a hollow porous ceramic filter plate, the width is 60-1000mm, the thickness is 2-10mm, the wall thickness is 0.5-5mm, the number of pore channels is 6-200, the size of the blank body corresponds to the size of an extrusion opening of a used die, and the size of the blank body is changed along with the change of the size of the extrusion opening of the die.
In the invention, the bending degree of the blank is preferably less than or equal to 1mm.
In the present invention, before sintering the green body, the green body may be further dried, preferably, the drying conditions include: the temperature is 80-150 deg.C, preferably 90-120 deg.C, and the time is 1-10 hr, preferably 2-8 hr.
In the present invention, the conditions for the sintering are not particularly limited, and the conditions for the sintering preferably include: the temperature is 1200-1600 ℃, and the preferable temperature is 1400-1550 ℃; the time is 1 to 15 hours, preferably 1 to 5 hours; further preferably, the temperature is raised to 1200-1600 ℃ at the temperature rising speed of 5-15 ℃/min, and then the temperature is preserved for 1-15h. In particular, the composition is used for preparing the fly ash-based porous ceramic, which is beneficial to industrial production operation and obtaining the fly ash-based porous ceramic with high porosity.
In a third aspect, the invention provides a fly ash-based porous ceramic prepared by the method provided in the second aspect.
In the fly ash-based porous ceramic prepared by the method provided by the invention, R = alumina content x 100%/(alumina content + silica content) > 0.72, namely, the fly ash-based porous ceramic provided by the invention has an aluminum-rich mullite crystal phase.
According to the present invention, preferably, the volume weight of the fly ash-based porous ceramic is 1.2 to 2g/cm 3 The average pore diameter is 0.5-10 μm, the porosity is 40-60%, the bending strength is 30-100MPa, the acid corrosion mass loss rate is less than or equal to 0.3%, the alkali corrosion mass loss rate is less than or equal to 0.5%, the acid corrosion bending strength loss rate is less than or equal to 10%, and the alkali corrosion bending strength loss rate is less than or equal to 10%.
According to a preferred embodiment of the present invention, the fly ash-based porous ceramic has a volume weight of 1.5 to 1.7g/cm 3 The average pore diameter is 0.6-2.5 μm, the porosity is 45-55%, the bending strength is 35-60MPa, the acid corrosion mass loss rate is less than or equal to 0.2%, the alkali corrosion mass loss rate is less than or equal to 0.3%, the acid corrosion bending strength loss rate is less than or equal to 8%, and the alkali corrosion bending strength loss rate is less than or equal to 9%.
In the invention, the volume weight parameter and the porosity parameter of the fly ash-based porous ceramic are respectively measured by GB/T1966-1996 test method for volume weight and apparent porosity of the porous ceramic; the average pore diameter parameter of the fly ash-based porous ceramic is measured by a bubble point and average flow method of GB/T32361-2015 separation membrane pore diameter test method; the flexural strength parameter of the fly ash-based porous ceramic is measured by a HYT 064-2002 tubular ceramic microporous filter membrane test method.
In the invention, acid corrosion quality loss rate is used for expressing acid resistance, and alkali corrosion quality loss rate is used for expressing alkali resistance, wherein the acid resistance and the alkali resistance are measured by GB/T1970-1996 porous ceramic acid and alkali corrosion resistance performance test method.
In the invention, preferably, the solid particles in the solid particles of the fly ash-based porous ceramic contain at least 50% of spherical particles, and in the invention, the fly ash-based porous ceramic retains the natural morphology of fly ash, which is beneficial to further improving the porosity of the fly ash-based porous ceramic.
In the invention, the content parameters of the spherical particles of the fly ash-based porous ceramic are measured by an electron scanning microscope, and specifically comprise the following steps: selecting 5 SEM pictures (magnification is 1000 times) for each fly ash-based porous ceramic sample, selecting an area of 300 multiplied by 300 mu m for each picture, and measuring the content of spherical particles with sphericity of more than 0.7 in the area in each picture, wherein the content is respectively marked as m 1 、m 2 、m 3 、m 4 And m 5 Wherein, the content of the spherical particles refers to the percentage of the number of particles with the sphericity of more than 0.7 in the determination area to the total number of the particles, and then the content of the fly ash-based porous ceramic spherical particles is = (m) 1 +m 2 +m 3 +m 4 +m 5 )/5. The sphericity is measured by a microscope, and the sphericity = (4 × pi × projection area)/(projection perimeter × projection perimeter).
The invention provides the application of the fly ash-based porous ceramic provided by the third aspect in building, sound absorption, water treatment and flue gas filtration.
The present invention will be described in detail below by way of examples.
The particle size parameters of the fly ash, the alumina, the titanium oxide and the copper oxide are all determined by a Malvern laser particle size analyzer MS 2000;
the content parameters of the spherical particles in the fly ash are measured by an electron scanning microscope, and specifically comprise the following steps: selecting 5 SEM pictures (magnification is 1000 times) for each fly ash sample, selecting 300 × 300 μm area for each picture, and measuring each pictureThe content of spherical morphology particles with sphericity greater than 0.7 in the region of the tablet is respectively recorded as m 1 、m 2 、m 3 、m 4 And m 5 Wherein, the content of the spherical particles refers to the percentage of the number of particles with sphericity of more than 0.7 in the determination area to the total number of particles, and then the content of the spherical particles in the fly ash is = (m) 1 +m 2 +m 3 +m 4 +m 5 )/5. Wherein the sphericity is measured by a microscope, and the sphericity = (4 × pi × projection area)/(projection perimeter × projection perimeter);
the volume weight parameter and the porosity parameter of the fly ash-based porous ceramic are respectively measured by GB/T1966-1996 porous ceramic volume weight and apparent porosity test method;
the average pore diameter parameter of the fly ash-based porous ceramic is measured by a bubble point and average flow method of GB/T32361-2015 separation membrane pore diameter test method;
the bending strength parameter of the fly ash-based porous ceramic is measured by a HYT 064-2002 tubular ceramic microporous filter membrane test method;
the acid and alkali resistance of the fly ash-based porous ceramic is measured by GB/T1970-1996 test method for acid and alkali corrosion resistance of porous ceramic;
the content parameter of the coal ash-based porous ceramic spherical morphology particles is measured by an electron scanning microscope, and specifically comprises the following steps: selecting 5 SEM pictures (magnification is 1000 times) for each fly ash-based porous ceramic sample, selecting an area of 300 multiplied by 300 mu m for each picture, and measuring the content of spherical particles with sphericity of more than 0.7 in the area in each picture, wherein the content is respectively marked as m 1 、m 2 、m 3 、m 4 And m 5 Wherein, the content of the spherical particles refers to the percentage of the number of particles with the sphericity degree of more than 0.7 in the measurement area to the total number of the particles, and then the content of the fly ash-based porous ceramic spherical particles = (m is the number of the particles with the spherical morphology and the particle size of the fly ash-based porous ceramic particles in the measurement area is the percentage of the total number of the particles in the measurement area to the total number of the particles in the measurement area, and the content of the fly ash-based porous ceramic particles in the measurement area is the same as the content of the particles with the spherical morphology and the particle size of the fly ash-based porous ceramic particles in the measurement area 1 +m 2 +m 3 +m 4 +m 5 )/5. The sphericity is measured by a microscope, and the sphericity = (4 × pi × projection area)/(projection perimeter × projection perimeter).
The amounts of the compositions used to produce the fly ash-based porous ceramics in examples 1-12 and comparative examples 1-2 are listed in table 1;
the components of the fly ash in the examples are all listed in table 2;
the physical property parameters of the fly ash-based porous ceramics obtained in examples 1 to 12 and comparative examples 1 to 2 are shown in Table 3.
Example 1
(1) Firstly mixing fly ash P1 (with the granularity of 10 mu m) and an organic forming agent to obtain a mixture; secondly mixing a dispersant, alumina (with the particle size of 0.3 mu m), alkaline earth metal oxide, titanium oxide (with the particle size of 1 mu m), copper oxide (with the particle size of 1 mu m) and an inorganic plasticizer with water to obtain a suspension; thirdly mixing the mixture and the suspension to obtain a mixture;
wherein the weight ratio of the fly ash P1 to the water is 1: 0.4, the content of spherical particles in the fly ash P1 is 70 percent, the organic forming agent is methylcellulose, the dispersing agent is ammonium polyacrylate (with the average molecular weight of 6000 g/mol), the alkaline earth metal oxide is magnesium oxide, and the inorganic plasticizer is kaolin;
(2) Ageing the mixture obtained in the step (1) at 25 ℃ for 36 hours, mechanically vacuum-pugging to obtain a wet blank section, putting the wet blank section into an extruder, and performing extrusion molding to obtain a hollow plate-shaped blank body a-1, wherein the width of the blank body is 110mm, the thickness of the blank body is 4mm, the wall thickness of the blank body is 1mm, and the number of pore passages is 35;
wherein, the bending degree of the blank body a-1 is measured to be 0mm;
(3) Drying the green body obtained in the step (2) at 100 ℃ for 4h, then heating to 1500 ℃ at the heating rate of 5 ℃/min, and preserving heat for 10h to obtain the fly ash-based porous ceramic A1;
the surface microscopic SEM image of the fly ash-based porous ceramic A1 is shown in fig. 1, and it can be seen from fig. 1 that the fly ash-based porous ceramic A1 has spherical morphology particles.
Example 2
(1) Firstly mixing fly ash P2 (the granularity is 20 mu m) with an organic forming agent to obtain a mixture; secondly mixing a dispersant, alumina (with the granularity of 1 mu m), alkaline earth metal oxide, titanium oxide (with the granularity of 4 mu m), copper oxide (with the granularity of 3 mu m), an inorganic plasticizer and water to obtain a suspension; thirdly mixing the mixture and the suspension to obtain a mixture;
wherein the weight ratio of the fly ash P2 to the water is 1: 0.45, the content of spherical particles in the fly ash P2 is 90 percent, the organic forming agent is carboxymethyl cellulose, the dispersing agent is polyacrylic acid (the average molecular weight is 10000 g/mol), the alkaline earth metal oxide is calcium oxide, and the inorganic plasticizer is bentonite;
(2) Ageing the mixture obtained in the step (1) at 25 ℃ for 36 hours, mechanically vacuum-pugging to obtain a wet blank section, putting the wet blank section into an extruder, and performing extrusion molding to obtain a plate-shaped blank body a-2;
wherein, the bending degree of the blank body a-2 is measured to be 0.1mm;
(3) Drying the green body obtained in the step (2) at 110 ℃ for 6h, then heating to 1550 ℃ at the heating rate of 5 ℃/min, and preserving heat for 3h to obtain the fly ash-based porous ceramic A2;
wherein, the surface microscopic SEM image of the fly ash-based porous ceramic A2 is similar to that of the fly ash-based porous ceramic A1, and the fly ash-based porous ceramic A has spherical particles.
Example 3
(1) Firstly mixing fly ash P3 (the granularity is 15 mu m) with an organic forming agent to obtain a mixture; secondly mixing a dispersant, alumina (with the particle size of 0.8 mu m), alkaline earth metal oxide, titanium oxide (with the particle size of 2 mu m), copper oxide (with the particle size of 2 mu m) and an inorganic plasticizer with water to obtain a suspension; thirdly mixing the mixture and the suspension to obtain a mixture;
wherein the weight ratio of the fly ash P3 to the water is 1: 0.5, the content of spherical particles in the fly ash P3 is 80 percent, the organic forming agent is hydroxypropyl methyl cellulose, the dispersing agent is citric acid, the alkaline earth metal oxide is calcium oxide, and the inorganic plasticizer is clay;
(2) Ageing the mixture obtained in the step (1) at 25 ℃ for 36 hours, mechanically vacuum-pugging to obtain a wet blank section, then putting the wet blank section into an extruder, and performing extrusion molding to obtain a plate-shaped blank body a-3;
wherein the bending degree of the blank body a-3 is measured to be 0.2mm;
(3) Drying the green body obtained in the step (2) at 120 ℃ for 5h, then heating to 1250 ℃ at the heating rate of 5 ℃/min, and preserving heat for 10h to obtain the fly ash-based porous ceramic A3;
wherein, the surface microscopic SEM image of the fly ash-based porous ceramic A3 is similar to that of the fly ash-based porous ceramic A1, and the fly ash-based porous ceramic A has spherical particles.
Example 4
According to the method of example 1, except that the amounts of the respective components were appropriately adjusted, the amounts of the respective components in the composition were as shown in Table 1, and the other steps were the same, the plate-like green body a-4 and the fly ash-based porous ceramic A4 were obtained.
Wherein, the bending degree of the tubular blank is measured to be 0.5mm;
the surface microscopic SEM image of the fly ash-based porous ceramic A4 was similar to that of fig. 1, with spherical morphology particles.
Example 5
The procedure of example 1 was followed, except that the amounts of the respective components were appropriately adjusted, the amounts of the respective components in the composition were as shown in Table 1, and the remaining steps were the same, to obtain a plate-like green body a-5 and a fly ash-based porous ceramic A5.
Wherein, the bending degree of the plate-shaped blank body a-5 is measured to be 0.5mm;
the surface microscopic SEM image of the fly ash-based porous ceramic A5 was similar to that of fig. 1, with spherical morphology particles.
Example 6
The procedure of example 1 was followed, except that the amounts of the respective components were appropriately adjusted, the amounts of the respective components in the composition were as shown in Table 1, and the remaining steps were the same, to obtain a plate-like green body a-6 and a fly ash-based porous ceramic A6.
Wherein, the bending degree of the plate-shaped blank body a-6 is measured to be 0mm;
the surface microscopic SEM image of the fly ash-based porous ceramic A6 was similar to fig. 1, with spherical morphology particles.
Example 7
The procedure of example 1 was followed, except that the amounts of the respective components were appropriately adjusted, the amounts of the respective components in the composition were as shown in Table 1, and the remaining steps were the same, to obtain plate-like green bodies a-7 and a fly ash-based porous ceramic A7.
Wherein the bending degree of the plate-shaped blank body a-7 is measured to be 0mm;
the surface microscopic SEM image of the fly ash-based porous ceramic A7 was similar to that of fig. 1, with spherical morphology particles.
Example 8
According to the method of example 1, except that fly ash P1 was replaced with fly ash P4, the specific components are shown in table 2, and the other steps were the same, a slab-like body a-8 and a fly ash-based porous ceramic A8 were obtained.
Wherein, the bending degree of the plate-shaped blank is measured to be 0mm;
the surface microscopic SEM image of the fly ash-based porous ceramic A8 was similar to that of fig. 1, with spherical morphology particles.
Example 9
According to the method of example 1, except that fly ash P1 is replaced by fly ash P5, the specific components are shown in Table 2, and the fly ash does not contain TiO 2 And the rest steps are the same, and the plate-shaped blank body a-9 and the fly ash-based porous ceramic A9 are obtained.
Wherein the bending degree of the plate-shaped blank body a-9 is measured to be 0mm;
the surface microscopic SEM image of the fly ash-based porous ceramic A9 was similar to that of fig. 1, with spherical morphology particles.
Example 10
The procedure of example 1 was followed, except that the particle size of fly ash was changed to 45 μm, and the remaining steps were the same, to obtain a plate-like body a-10 and a fly ash-based porous ceramic a10.
Wherein the bending degree of the plate-shaped blank body a-10 is measured to be 0mm;
the surface microscopic SEM image of the fly ash-based porous ceramic a10 was similar to fig. 1, with spherical morphology particles.
Example 11
The procedure of example 1 was followed, except that the particle size of alumina was changed to 5 μm, and the remaining steps were the same, to obtain a plate-like body a-11 and a fly ash-based porous ceramic A11.
Wherein, the bending degree of the plate-shaped blank body a-11 is measured to be 0mm;
the surface microscopic SEM image of the fly ash-based porous ceramic a11 was similar to that of fig. 1, with spherical morphology particles.
Example 12
According to the method of the embodiment 1, except that the fly ash P1, the organic forming agent, the dispersing agent, the alumina, the alkaline earth metal oxide, the titanium oxide, the copper oxide, the inorganic plasticizer and the water are directly mixed to obtain a mixture, and the rest steps are the same to obtain the plate-shaped green body a-12 and the fly ash-based porous ceramic A12.
Wherein, the bending degree of the plate-shaped blank body a-12 is measured to be 0mm;
the surface microscopic SEM image of the fly ash-based porous ceramic a12 was similar to that of fig. 1, with spherical morphology particles.
Comparative example 1
Following the procedure of example 1, except that the amounts of the respective components in the composition were varied as shown in Table 1, the remaining steps were the same, to obtain a plate-like green body D-1 and a fly ash-based porous ceramic D1.
The bending of the plate-like blank d-1 was measured to be 0mm.
Comparative example 2
According to the method of example 1, except that, in the step (1), the fly ash P1 is ground to make the particle size of the fly ash P1 to be 10 μm, and a pore-forming agent (starch) is added, the amounts of the components in the composition are shown in table 1, and the rest steps are the same, a plate-shaped green body D-2 and a fly ash-based porous ceramic D2 are obtained.
The bending of the plate-like blank d-2 was measured to be 0mm.
TABLE 1
Figure BDA0003003723140000191
Figure BDA0003003723140000201
TABLE 1
Figure BDA0003003723140000202
TABLE 2
Figure BDA0003003723140000203
TABLE 3
Coal ash based porous ceramic A1 A2 A3 A4 A5 A6 A7
Volume weight, g/cm 3 1.7 1.6 1.6 2 1.7 1.7 1.7
Average pore diameter, μm 0.7 2.5 1.2 0.5 0.7 0.7 0.7
Porosity% 45 52 48 40 45 45 45
Flexural strength, MPa 60 35 43 30 30 32 31
Acid corrosion mass loss rate% 0.2 0.1 0.1 0.2 0.2 0.2 0.2
Alkali corrosion mass loss rate% 0.3 0.2 0.2 0.3 0.3 0.3 0.3
The rate of loss of bending strength by acid etching% 4.8 5.8 5.3 9.5 9.5 9.5 9.5
Corrosion bending strength loss rate% 4.6 7.2 5.8 9.5 9.5 9.5 9.5
Spherical morphology particle content (%) 66 61 62 58 57 56 55
TABLE 3
Coal ash based porous ceramic A8 A9 A10 A11 A12 D1 D2
Volume weight, g/cm 3 2 2 1.9 1.9 2 2.7 2.9
Average pore diameter, μm 0.5 0.5 4.8 0.8 4 5 0.3
Porosity% 40 40 41 42 40 28 26
Flexural strength, MPa 35 30 31 30 33 21 16
Acid corrosion mass loss rate% 0.3 0.3 0.3 0.3 0.3 1 1.5
Alkali corrosion mass loss rate% 0.3 0.5 0.5 0.5 0.3 1.5 5
The rate of loss of bending strength by acid etching% 9.5 9.5 9.5 10 9.5 15.6 21
Corrosion bending strength loss rate% 9.5 10 9.5 10 9.5 24.2 28
Spherical morphology particle content (%) 53 51 54 52 58 48 42
As can be seen from the results in tables 1 to 3, the fly ash-based porous ceramic prepared by using the composition for producing a fly ash-based porous ceramic according to the present invention has high porosity, bending strength and acid and alkali resistance (acid corrosion mass loss rate and alkali corrosion mass loss rate are small, acid corrosion bending strength loss rate and alkali corrosion bending strength loss rate are small), and particularly, in the solid particles of the fly ash-based porous ceramic, the solid particles contain at least 50% of spherical-shaped particles, and the fly ash-based porous ceramic obtained according to the present invention retains the natural morphology of fly ash, which is helpful for further improving the porosity, bending strength and acid and alkali resistance of the fly ash-based porous ceramic.
The preferred embodiments of the present invention have been described above in detail, but the present invention is not limited thereto. Within the scope of the technical idea of the invention, many simple modifications can be made to the technical solution of the invention, including combinations of various technical features in any other suitable way, and these simple modifications and combinations should also be regarded as the disclosure of the invention, and all fall within the scope of the invention.

Claims (10)

1. A composition for producing a fly ash-based porous ceramic, the composition comprising: the composite material comprises fly ash, an organic forming agent, a dispersing agent, IIIA group metal oxide, alkaline earth metal oxide, IVB group metal oxide, IB group metal oxide and an inorganic plasticizer;
wherein, based on the total weight of the composition, the content of the fly ash is 72-89.5wt%, the content of the organic forming agent is 4-9wt%, the content of the dispersant is 0.2-1wt%, the content of the IIIA group metal oxide is 3-8wt%, the content of the alkaline earth metal oxide is 0.1-1wt%, the content of the IVB group metal oxide is 0.1-1.5wt%, the content of the IB group metal oxide is 0.1-1.5wt%, and the content of the inorganic plasticizer is 3-6wt%.
2. The composition as claimed in claim 1, wherein the fly ash is contained in an amount of 78-88wt%, the organic forming agent is contained in an amount of 3-6wt%, the dispersant is contained in an amount of 0.5-1wt%, the group IIIA metal oxide is contained in an amount of 3-6wt%, the alkaline earth metal oxide is contained in an amount of 0.5-1wt%, the group IVB metal oxide is contained in an amount of 0.5-1wt%, the group IB metal oxide is contained in an amount of 0.5-1wt%, and the inorganic plasticizer is contained in an amount of 4-6wt%, based on the total weight of the composition.
3. The composition according to claim 1 or 2, wherein the fly ash has a content of spherical-shaped particles of 60-90%, preferably 65-85%, and a content of non-spherical-shaped particles of 10-40%, preferably 15-35%;
preferably, the fly ash has a particle size of 1-100 μm, preferably 10-30 μm.
4. A composition as claimed in any one of claims 1 to 3, wherein the fly ash contains a component M selected from TiO 2 At least one of CaO and MgO, and the content of the component M is 2-5wt%, preferably 3-4wt% based on the total weight of the fly ash;
preferably, the component M is selected from TiO 2 At least two of CaO and MgO, preferably TiO 2 And CaO, and TiO 2 The weight ratio of CaO and CaO is 1: 0.6-2, preferably 1: 1-1.5;
preferably, the fly ash also contains Al 2 O 3 And SiO 2 (ii) a Taking the total weight of the fly ash as a reference, al in the fly ash 2 O 3 In an amount of from 35 to 70wt%, preferably from 40 to 60wt%; siO 2 2 The content of (B) is 15 to 60wt%, preferably 35 to 50wt%.
5. The composition according to any one of claims 1 to 4, wherein the organic forming agent is selected from at least one of methylcellulose, carboxymethylcellulose, hydroxypropylmethylcellulose, polyvinyl alcohol and polyanionic cellulose;
preferably, the dispersant is selected from at least one of ammonium polyacrylate, sodium polyacrylate, polyacrylic acid, citric acid and sodium citrate;
preferably, the group IIIA metal oxide is alumina;
preferably, the particle size of the alumina is 0.1 to 5 μm, preferably 0.3 to 1 μm;
preferably, the group IVB metal oxide is titanium oxide;
preferably, the titanium oxide has a particle size of 0.1 to 10 μm, preferably 0.5 to 4 μm;
preferably, the group IB metal oxide is copper oxide;
preferably, the particle size of the copper oxide is 0.1-8 μm, preferably 0.5-3 μm;
preferably, the alkaline earth metal oxide is selected from magnesium oxide and/or calcium oxide;
preferably, the inorganic plasticizer is selected from at least one of kaolin, bentonite, and clay.
6. A method for preparing a fly ash-based porous ceramic, characterized by comprising the steps of:
(1) Mixing the composition of any one of claims 1-5 with water and then shaping;
(2) And sintering the formed blank to obtain the fly ash-based porous ceramic.
7. The method of claim 6, wherein the mixing in step (1) comprises:
1) Carrying out first mixing on the fly ash and an organic forming agent to obtain a mixture;
2) Secondly mixing the dispersant, IIIA group metal oxide, alkaline earth metal oxide, IVB group metal oxide, IB group metal oxide and inorganic plasticizer with water to obtain suspension;
3) Thirdly mixing the mixture and the suspension to obtain a mixture;
preferably, the weight ratio of the fly ash to the water is 1: 0.2-0.6, preferably 1: 0.35-0.55.
8. A method according to claim 6 or 7, wherein the body has a bow of less than or equal to 1mm;
preferably, the sintering conditions include: the temperature is 1200-1600 ℃, and the preferable temperature is 1400-1550 ℃; the time is 1-15h, preferably 1-5h.
9. A fly ash-based porous ceramic produced by the method of any one of claims 6-8;
preferably, the volume weight of the fly ash-based porous ceramic is 1.2-2g/cm 3 The average pore diameter is 0.5-10 μm, the porosity is 40-60%, the bending strength is 30-100MPa, the acid corrosion mass loss rate is less than or equal to 0.3%, the alkali corrosion mass loss rate is less than or equal to 0.5%, the acid corrosion bending strength loss rate is less than or equal to 10%, and the alkali corrosion bending strength loss rate is less than or equal to 10%;
preferably, the volume weight of the fly ash-based porous ceramic is 1.5-1.7g/cm 3 The average pore diameter is 0.6-2.5 μm, the porosity is 45-55%, the bending strength is 35-60MPa, the acid corrosion mass loss rate is less than or equal to 0.2%, the alkali corrosion mass loss rate is less than or equal to 0.3%, the acid corrosion bending strength loss rate is less than or equal to 8%, and the alkali corrosion bending strength loss rate is less than or equal to 9%;
preferably, the solid particles of the fly ash-based porous ceramic contain at least 50% of spherical morphology particles.
10. Use of the fly ash-based porous ceramic of claim 9 in construction, sound absorption, water treatment and flue gas filtration.
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CN101643359A (en) * 2009-08-04 2010-02-10 陕西科技大学 Method for preparing porzite powder by fly ash
CN102241500A (en) * 2010-05-16 2011-11-16 由伟 Artificial jade based on fly ash and manufacturing method thereof
CN105084867A (en) * 2015-08-05 2015-11-25 澧县新鹏陶瓷有限公司 Antibiosis ceramic product with coal ash as main raw material and preparing method of antibiosis ceramic product
CN106747319A (en) * 2017-01-22 2017-05-31 北方民族大学 Standby porous ceramics of a kind of utilization magnesium slag, coal ash for manufacturing and preparation method thereof
WO2018134334A1 (en) * 2017-01-20 2018-07-26 Consorzio Interuniversitario Nazionale Per La Scienza E Tecnologia Dei Materiali Process for obtaining a porous material from powder materials, a porous material and use thereof for the capture of atmospheric particulate matter and organic contaminants

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101643359A (en) * 2009-08-04 2010-02-10 陕西科技大学 Method for preparing porzite powder by fly ash
CN102241500A (en) * 2010-05-16 2011-11-16 由伟 Artificial jade based on fly ash and manufacturing method thereof
CN105084867A (en) * 2015-08-05 2015-11-25 澧县新鹏陶瓷有限公司 Antibiosis ceramic product with coal ash as main raw material and preparing method of antibiosis ceramic product
WO2018134334A1 (en) * 2017-01-20 2018-07-26 Consorzio Interuniversitario Nazionale Per La Scienza E Tecnologia Dei Materiali Process for obtaining a porous material from powder materials, a porous material and use thereof for the capture of atmospheric particulate matter and organic contaminants
CN106747319A (en) * 2017-01-22 2017-05-31 北方民族大学 Standby porous ceramics of a kind of utilization magnesium slag, coal ash for manufacturing and preparation method thereof

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