CN103936400B - Alumina based porous ceramic thermal insulation material and preparation method - Google Patents
Alumina based porous ceramic thermal insulation material and preparation method Download PDFInfo
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- CN103936400B CN103936400B CN201410103189.7A CN201410103189A CN103936400B CN 103936400 B CN103936400 B CN 103936400B CN 201410103189 A CN201410103189 A CN 201410103189A CN 103936400 B CN103936400 B CN 103936400B
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Abstract
The invention provides an alumina based porous ceramic thermal insulation material and a preparation method. The raw materials comprise alumina hollow balls, high alumina bauxite, aluminum hydroxide, sodium bentonite, magnesium carbonate superfine powder and acid aluminum calcium composite phosphate sol. The forming principle is as follows: the raw materials are prepared into ceramic slurry, then are quickly stirred well, and poured into a steel mould, a chemical reaction of free phosphoric acid in the aluminum calcium composite phosphate sol and the magnesium carbonate superfine powder in the slurry is performed to produce a large number of tiny CO2 bubbles to cause expansion of the slurry and appearance of a porous honeycomb shape; after the honeycomb-shaped pores in the slurry are stable, the mould is put into a heating furnace with the furnace temperature ranged from 500 to 600 DEG C for heating curing and low-temperature sintering of ceramics to prepare the alumina based porous ceramic thermal insulation material. The honeycomb-shaped pores in the alumina based porous ceramic thermal insulation material are in sealing-shaped structures, so that the heat convection of air can be effectively isolated, and the thermal insulation effect is excellent.
Description
Technical field
The invention belongs to lagging material technical field, be specifically related to a kind of alumina oxide matrix porous ceramic thermal insulation material for industrial heating furnace inside holding and preparation method.
Background technology
The initial multiplex light fire brick of industrial heating furnace inside thermal conservation material, porous foam brick, rear development adopts aluminosilicate system ceramic fiber blanket or the fibre products etc. such as pure aluminium silicate, mullite, aluminum oxide.The general use temperature of these fiber-like lagging materials is at 1000 ~ 1300 DEG C.The advantage of fiber heat preservation material is that light weight, thermal conductivity are little, easy construction, and high insulating effect, widely uses in industrial heating furnace field at present.
Manosil AS system ceramic wool insulation material and goods, also exist that raw materials cost is high, complex manufacturing technology and the problem such as energy consumption is large.In addition, aluminosilicate system ceramic fiber internal structure is uneven, in use also there is the problems such as ceramic fiber at high temperature life-time service easy recrystallize efflorescence, fiber cotton-shapedly come off, heat-insulating property reduction, shortening in work-ing life.Manosil AS system ceramic fiber hole is opening shape, and the warm air in hole easily forms thermal convection with cool exterior air, and causing increasing of dispelling the heat, actual energy-saving effect will be given a discount, and energy consumption is still very high.
Summary of the invention
The present invention, in order to overcome the defect existed in prior art, provides a kind of alumina oxide matrix porous ceramic thermal insulation material and the preparation method with good insulation and thermal shock resistance.
A preparation method for alumina oxide matrix porous ceramic thermal insulation material, comprises the following steps:
(1) the aluminium calcium compound phosphoric acid salt sol of 51 ~ 59 weight parts is added stirrer, add the alumina hollow ball of 36 ~ 45 weight parts, the aluminium hydroxide of 8 ~ 12 weight parts, the alumine of 13 ~ 17 weight parts, the sodium bentonite of 10 ~ 17 weight parts again, stir; Add the magnesiumcarbonate of 0.4 ~ 1.3 weight part again, and high-speed stirring 10 ~ 15s, form slurry, slurry is poured in mould, leave standstill and make it to expand;
(2) stop after expansion until slurry, mould is put into the process furnace heating 1 ~ 2h of 500 ~ 600 DEG C, namely slurry curing obtains alumina oxide matrix porous ceramic thermal insulation material.
The preparation method of described aluminium calcium compound phosphoric acid salt sol, comprise the following steps: the industrial phosphoric acid being 85% by 95 ~ 100 weight part concentration mixes with the water of 25 ~ 30 weight parts, pour in reactor, when being heated to boiling, slowly add the aluminium-hydroxide powder of 36 ~ 40 weight parts, and continue heating and make it to dissolve completely, form transparent acidic sol; Be cooled to room temperature after colloidal sol being continued heating 30 ~ 40min, add the calcium carbonate of 4 ~ 6 weight parts, react with transparent acid colloidal sol and produce to bubble-free, then add water by colloidal sol Auto-regulating System of Density of Heavy Medium to 1.45 ~ 1.5g/cm
3, make aluminium calcium compound phosphoric acid salt sol.
The particle diameter of described alumina hollow ball is 0.2 ~ 1.5mm, Al
2o
3content>=96%, unit weight is 0.3 ~ 0.5g/cm
3.
The fineness of described alumine is 260 ~ 325 orders, Al
2o
3content>=86%.
The fineness of described aluminium-hydroxide powder is 600 ~ 700 orders, Al(OH)
3content>=99%.
Swell value >=the 96mL/3g of described sodium bentonite.
Described magnesiumcarbonate is Magnesium Carbonate Light 41-45, and its fineness is 1000 ~ 1500 orders.
The pH value of described aluminium calcium compound phosphoric acid salt sol is 1.5 ~ 2, and density is 1.45 ~ 1.50g/cm
3.
Described alumina oxide matrix porous ceramic thermal insulation material preparation method obtains a porous ceramic thermal insulation material, and it is characterized in that, starting material comprise the material of following weight part:
Described alumina oxide matrix porous ceramic thermal insulation material, its physical performance index is: ultimate compression strength 1.5 ~ 2.0MPa, and unit weight is 0.3 ~ 0.5g/cm
3, thermal conductivity is 0.1 ~ 0.3W/mK, and refractoriness is 1300 ~ 1400 DEG C.
The Forming Theory of alumina oxide matrix porous ceramic thermal insulation material provided by the invention is: ceramic size is made up of alumina material (alumina hollow ball, bauxitic clay, aluminium hydroxide, sodium bentonite etc.) and acid aluminium calcium compound phosphoric acid salt sol, when adding the magnesiumcarbonate ultrafine powder of trace, and rapid stirring is even, pour in steel die, the free phosphoric acid (H in the acidic aluminum calcium compound phosphoric acid salt sol in slurry
3pO
4) and magnesiumcarbonate (MgCO
3) ultrafine powder generation chemical reaction, generate a large amount of small CO
2bubble, causes slurry to expand.Chemical equation is as follows:
2H
3PO
4+3MgCO
3=Mg
3(PO
4)
2+3CO
2↑+3H
2O
Because slurry viscosity is very large, the small bubbles of formation cannot float effusion slurry, are trapped in slurry, make slurry present porous honeycomb.After slurry internal cellular shape hole is stable, mould is put into the process furnace that furnace temperature is 500 ~ 600 DEG C, carry out being heating and curing and low-temp ceramics sintering.In this temperature range, the aluminium dihydrogen phosphate [Al (H in aluminium calcium compound phosphoric acid salt sol
2pO
4)
3] with slurry in aluminum oxide (Al
2o
3) reaction, generate aluminum oxide (Al
2o
3)-aluminum phosphate (AlPO
4) porous ceramic skeleton and make slurry curing, chemical equation is as follows:
Al
2O
3+Al(H
2PO
4)
3=3AlPO
4+3H
2O
Because the cellular porosity in alumina oxide matrix porous ceramic thermal insulation material is closed structure, effectively completely cut off the thermal convection of air, made it have fabulous heat insulation effect.Alumina oxide matrix porous ceramic thermal insulation material prepared by the present invention, for the industrial heating furnace of temperature below 1300 DEG C, is the desirable lightening fire resistant lagging material of alternative widely used manosil AS system ceramic fiber and goods.
Alumina oxide matrix porous ceramic thermal insulation material provided by the invention has the following advantages compared with traditional lagging material:
(1) preparation technology of the present invention is simple, and ceramic sintering temperature is low, and energy consumption is little, and production cost is low, and obtained lagging material voidage is high, and micropore is evenly distributed, and thermal conductivity is little, intensity is high, not efflorescence in life-time service, does not ftracture, long service life.
(2) the present invention prepare alumina oxide matrix porous ceramic thermal insulation material hole enormous amount, be evenly distributed, and each hole is closed, and thermal conductivity is little, intensity is high, has good insulation and thermal shock resistance.
Embodiment
Below in conjunction with specific embodiment, technical scheme of the present invention is further illustrated.
Embodiment 1
(1) industrial phosphoric acid being 85% by 95 weight part concentration mixes with the water of 25 weight parts, pours in reactor, when being heated to boiling, slowly adds the aluminium-hydroxide powder of 36 weight parts, and continues heating and make it to dissolve completely, forms transparent acid colloidal sol; Again by cool to room temperature after transparent acid colloidal sol continuation heating 30min, add the calcium carbonate of 4 weight parts, react with transparent acid colloidal sol, release CO
2bubble, till bubble-free produces, then adds appropriate water by colloidal sol Auto-regulating System of Density of Heavy Medium to 1.45g/cm
3, make acid aluminium calcium compound phosphoric acid salt sol.
(2) pour the aluminium calcium compound phosphoric acid salt sol of 51 weight parts into stirrer, then add alumina hollow ball, the aluminium hydroxide of 8 weight parts, the high-aluminium vanadine of 13 weight parts, the sodium bentonite of 10 weight parts of 36 weight parts, stir; Add the magnesiumcarbonate of 0.4 weight part again, and high-speed stirring 10s, form slurry, slurry is poured in steel die.At this moment the acidic aluminum calcium compound phosphoric acid salt sol generation chemical reaction in magnesiumcarbonate and slurry, produces a large amount of CO in the slurry
2small bubbles, make slurry expand, and form cellular structures;
Etc. (3) after slurry expands and stops, metal die being put into furnace temperature is that the process furnace of 500 DEG C sinters 1h, aluminum oxide in aluminium calcium compound phosphoric acid salt sol in slurry and aluminium hydroxide, high-aluminium vanadine, hollow alumina, sodium bentonite is reacted, generate alumina-aluminum phosphate porous ceramic skeleton, make slurry curing and make alumina oxide matrix porous ceramic thermal insulation material.
Embodiment 2
(1) industrial phosphoric acid being 85% by 98 weight part concentration mixes with the water of 27 weight parts, pours in reactor, when being heated to boiling, slowly adds the aluminium-hydroxide powder of 38 weight parts, and continues heating and make it to dissolve completely, forms transparent acid colloidal sol; Again by cool to room temperature after transparent acid colloidal sol continuation heating 35min, add the calcium carbonate of 5 weight parts, react with transparent acid colloidal sol, release CO
2bubble, till bubble-free produces, then adds appropriate water by colloidal sol Auto-regulating System of Density of Heavy Medium to 1.47g/cm
3, make acid aluminium calcium compound phosphoric acid salt sol.
(2) pour the aluminium calcium compound phosphoric acid salt sol of 59 weight parts into stirrer, then add alumina hollow ball, the aluminium hydroxide of 10 weight parts, the high-aluminium vanadine of 15 weight parts, the sodium bentonite of 14 weight parts of 40 weight parts, stir; Add the magnesiumcarbonate of 0.8 weight part again, and high-speed stirring 12s, form slurry, slurry is poured in steel die.At this moment the acidic aluminum calcium compound phosphoric acid salt sol generation chemical reaction in magnesiumcarbonate and slurry, produces a large amount of CO in the slurry
2small bubbles, make slurry expand, and form cellular structures;
Etc. (3) after slurry expands and stops, metal die being put into furnace temperature is that the process furnace of 550 DEG C sinters 1.5h, aluminum oxide in aluminium calcium compound phosphoric acid salt sol in slurry and aluminium hydroxide, high-aluminium vanadine, hollow alumina, sodium bentonite is reacted, generate alumina-aluminum phosphate porous ceramic skeleton, make slurry curing and make alumina oxide matrix porous ceramic thermal insulation material.
Embodiment 3
(1) industrial phosphoric acid being 85% by 100 weight part concentration mixes with the water of 30 weight parts, pours in reactor, when being heated to boiling, slowly adds the aluminium-hydroxide powder of 40 weight parts, and continues heating and make it to dissolve completely, forms transparent acid colloidal sol; Again by cool to room temperature after transparent acid colloidal sol continuation heating 40min, add the calcium carbonate of 6 weight parts, react with transparent acid colloidal sol, release CO
2bubble, till bubble-free produces, then adds appropriate water by colloidal sol Auto-regulating System of Density of Heavy Medium to 1.5g/cm
3, make aluminium calcium compound phosphoric acid salt sol.
(2) pour the aluminium calcium compound phosphoric acid salt sol of 55 weight parts into stirrer, then add alumina hollow ball, the aluminium hydroxide of 12 weight parts, the high-aluminium vanadine of 17 weight parts, the sodium bentonite of 17 weight parts of 45 weight parts, stir; Add the magnesiumcarbonate of 1.3 weight parts again, and high-speed stirring 15s, form slurry, slurry is poured in steel die.At this moment the acidic aluminum calcium compound phosphoric acid salt sol generation chemical reaction in magnesiumcarbonate and slurry, produces a large amount of CO in the slurry
2small bubbles, make slurry expand, and form cellular structures;
Etc. (3) after slurry expands and stops, metal die being put into furnace temperature is that the process furnace of 600 DEG C sinters 2.0h, aluminum oxide in aluminium calcium compound phosphoric acid salt sol in slurry and aluminium hydroxide, high-aluminium vanadine, hollow alumina, sodium bentonite is reacted, generate alumina-aluminum phosphate porous ceramic skeleton, make slurry curing and make alumina oxide matrix porous ceramic thermal insulation material.
Above-described embodiment; further detailed description has been carried out to object of the present invention, technical scheme and beneficial effect; be understood that; the foregoing is only specific examples of the present invention; be not limited to the present invention; within the spirit and principles in the present invention all, any amendment made, equivalent replacement, improvement etc., all should be included within protection scope of the present invention.
Claims (8)
1. a preparation method for alumina oxide matrix porous ceramic thermal insulation material, is characterized in that, comprise the following steps:
(1) the aluminium calcium compound phosphoric acid salt sol of 51 ~ 59 weight parts is added stirrer, add the alumina hollow ball of 36 ~ 45 weight parts, the aluminium hydroxide of 8 ~ 12 weight parts, the alumine of 13 ~ 17 weight parts, the sodium bentonite of 10 ~ 17 weight parts again, stir; Add the magnesiumcarbonate of 0.4 ~ 1.3 weight part again, and high-speed stirring 10 ~ 15s, form slurry, slurry is poured in mould, leave standstill and make it to expand;
(2) stop after expansion until slurry, mould is put into the process furnace heating 1 ~ 2h of 500 ~ 600 DEG C, namely slurry curing obtains alumina oxide matrix porous ceramic thermal insulation material;
The preparation method of described aluminium calcium compound phosphoric acid salt sol, comprise the following steps: the industrial phosphoric acid being 85% by 95 ~ 100 weight part concentration mixes with the water of 25 ~ 30 weight parts, pour in reactor, when being heated to boiling, slowly add the aluminium-hydroxide powder of 36 ~ 40 weight parts, and continue heating and make it to dissolve completely, form transparent acidic sol; Be cooled to room temperature after colloidal sol being continued heating 30 ~ 40min, add the calcium carbonate of 4 ~ 6 weight parts, react with transparent acid colloidal sol and produce to bubble-free, then add water by colloidal sol Auto-regulating System of Density of Heavy Medium to 1.45 ~ 1.5g/cm
3, make aluminium calcium compound phosphoric acid salt sol.
2. the preparation method of alumina oxide matrix porous ceramic thermal insulation material according to claim 1, is characterized in that, the particle diameter of described alumina hollow ball is 0.2 ~ 1.5mm, Al
2o
3content>=96%, unit weight is 0.3 ~ 0.5g/cm
3.
3. the preparation method of alumina oxide matrix porous ceramic thermal insulation material according to claim 1, is characterized in that, the fineness of described alumine is 260 ~ 325 orders, Al
2o
3content>=86%.
4. the preparation method of alumina oxide matrix porous ceramic thermal insulation material according to claim 1, is characterized in that, the fineness of described aluminium-hydroxide powder is 600 ~ 700 orders, Al (OH)
3content>=99%.
5. the preparation method of alumina oxide matrix porous ceramic thermal insulation material according to claim 1, is characterized in that, the swell value >=96mL/3g of described sodium bentonite.
6. the preparation method of alumina oxide matrix porous ceramic thermal insulation material according to claim 1, is characterized in that, described magnesiumcarbonate is Magnesium Carbonate Light 41-45, and its fineness is 1000 ~ 1500 orders.
7. the preparation method of alumina oxide matrix porous ceramic thermal insulation material according to claim 1, is characterized in that, the pH value of described aluminium calcium compound phosphoric acid salt sol is 1.5 ~ 2, and density is 1.45 ~ 1.50g/cm
3.
8. preparation method according to claim 1 obtains an alumina oxide matrix porous ceramic thermal insulation material, it is characterized in that, starting material comprise the material of following weight part:
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| CN104446635B (en) * | 2014-11-10 | 2016-05-18 | 西北工业大学 | A kind of preparation method of obturator-type Woelm Alumina thermal insulation ceramics |
| CN105110771A (en) * | 2015-07-24 | 2015-12-02 | 合肥凯士新材料贸易有限公司 | Flake alumina porous ceramic used for high-power LED lamp chip heat dissipation, and preparation method thereof |
| CN108383551A (en) * | 2018-04-17 | 2018-08-10 | 山东理工大学 | A kind of preparation method of alumina-aluminum phosphate layered insulation ceramics |
| CN109020478A (en) * | 2018-08-06 | 2018-12-18 | 杭州景杰陶瓷科技有限公司 | A kind of preparation method of lightweight Over-summer cultivation carcass and its injecting paste material and the injecting paste material |
| CN108947568B (en) * | 2018-08-16 | 2021-03-23 | 中钢集团洛阳耐火材料研究院有限公司 | Method for preparing alumina hollow ball brick by using pore-forming agent |
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| CN101343174A (en) * | 2008-08-20 | 2009-01-14 | 哈尔滨工业大学 | Aluminum oxide/alumina titanate ceramica composite material and preparation thereof |
| CN101386546A (en) * | 2008-10-14 | 2009-03-18 | 华南理工大学 | Self-reacting alumina-base composite ceramic mold core for fine casting and preparation method thereof |
| CN102887698A (en) * | 2011-07-22 | 2013-01-23 | 清华大学 | Indium oxide based ceramic composite thermoelectric material and preparation method thereof |
| CN103224387A (en) * | 2013-05-02 | 2013-07-31 | 湖南泰鑫瓷业有限公司 | AL2O3-Fe base ceramic composite material and production method thereof |
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| JPH0797269A (en) * | 1993-09-27 | 1995-04-11 | Mitsubishi Materials Corp | Production of low-temperature sintering ceramic |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101343174A (en) * | 2008-08-20 | 2009-01-14 | 哈尔滨工业大学 | Aluminum oxide/alumina titanate ceramica composite material and preparation thereof |
| CN101386546A (en) * | 2008-10-14 | 2009-03-18 | 华南理工大学 | Self-reacting alumina-base composite ceramic mold core for fine casting and preparation method thereof |
| CN102887698A (en) * | 2011-07-22 | 2013-01-23 | 清华大学 | Indium oxide based ceramic composite thermoelectric material and preparation method thereof |
| CN103224387A (en) * | 2013-05-02 | 2013-07-31 | 湖南泰鑫瓷业有限公司 | AL2O3-Fe base ceramic composite material and production method thereof |
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