NL2024151B1 - High-temperature resistant silicon-based aerogel powder and preparation method thereof - Google Patents

Abstract

The present invention provides high-temperature resistant silicon-based aerogel powder. The high-temperature resistant silicon-based aerogel powder includes the following substances in parts by mole: 1-2 mole parts of a binary silicon-based oxide, and 1-2 mole parts of water glass. The present invention further provides a preparation method for the high-temperature resistant silicon-based aerogel powder. The high-temperature resistant silicon-based aerogel in the present invention is a general-type material in the high-temperature heat-insulating field, is capable of solving a problem in the high-temperature heat-insulating field that a high-performance nano heat-insulating material is sparse extremely, and can be used for high-temperature industrial equipment of a high-temperature industrial furnace, a smelting furnace, a petrochemical cracking furnace and the like and materials of wood, steel and the like which need high-temperature fire-proof protection. Application scenarios are very extensive, and a potential market value is huge.

Description

High-temperature resistant silicon-based aerogel powder and preparation method thereof Technical Field The present invention relates to the field of aerogel, and in particular to high-temperature resistant silicon-based aerogel powder and a preparation method thereof. Background Aerogel is a dazzling new star in the new material field in recent years. In August 19, 2007, <The Sunday Times> of Britain publishes an article of "Miracle material capable of changing the world - aerogel"; in December, 2014, in future top ten potential new materials issued by a new material online "new material capital and technology summit”, the aerogel is ranked in a third place; and in June, 2014, the America Allied market research company reports that a global aerogel market value is expected to reach 1.9 billion dollars in 2020, and a compound annual growth rate is 36.4%. In April, 2016, "Aerogel Innovation and Application Promotion Center” licensed by the Ministry of Industry and Information Technology of the People's Republic of China is established. Under encouragement and support of government departments, more and more specialists and scholars, professional research institutes, enterprises and investment forces begin to pay attention to and research the aerogel material, so far there are more than ten sized enterprises professionally working on aerogel material production in the market, and four times of national aerogel seminars specially in allusion to the aerogel material have been held, and in various scales and grades of innovation and venture competitions, a figure of the "aerogel" appears frequently. The aerogel is rapidly grown to be a core force for supporting traditional industry transformation and upgrading, and emerging industry rising and growing.

The aerogel may be formed by multiple materials of an inorganic material, an organic material and the like, herein a silicon oxide aerogel technology is most mature, production cost is lowest, and it has been applied in the fields of petrifaction pipe insulation and the like in a mode of a heat-insulating quilt. However, a nano pore canal of the silicon oxide aerogel beings to collapse in more than 800 °C, and a 1 heat-insulating effect is basically lost in an occasion of which a temperature is higher than 1000 °C, so the silicon oxide aerogel may not be used for the high-temperature heat-preserving heat-insulating field. A silicon-based ceramic material has high-temperature resistant performance apparently higher than that of the silicon oxide material, for example, aluminum silicate may be used for a long time in 1200 °C of an environment, and temperature resistance of mullite (aluminosilicate compound) and zirconium silicate may reach 1500 and 1700 °C respectively. However a research report related to the silicon-based high-temperature resistant aerogel material is not seen yet now in the international.

Summary The present invention aims to provide high-temperature resistant silicon-based aerogel powder and a preparation method thereof in allusion to deficiency of an existing technology.

An innovation point of the present invention is that the high-temperature resistant silicon-based aerogel powder in the present invention is a general-type material in the high-temperature heat-insulating field, is capable of solving a problem in the high-temperature heat-insulating field that a high-performance nano heat-insulating material is sparse extremely, and may be used for high-temperature industrial equipment of a high-temperature industrial furnace, a smelting furnace, a petrochemical cracking furnace and the like and materials of wood, steel and the like which need high-temperature fire-proof protection, application scenarios are very extensive, and a potential market value is huge.

Technical scheme: in order to achieve the above purpose of the present invention, the present invention is specifically realized by such a mode: the high-temperature resistant silicon-based aerogel powder includes the following substances in parts by mole: 1-2 mole parts of a binary silicon-based oxide, and 1-2 mole parts of water glass. A traditional silicon oxide material is not well in high-temperature resistant performance, in order to realize a high-temperature resistant aerogel structure in a silicon-based material system, doping modification must be performed on a silicon-based framework, and temperature resistant performance thereof is improved. The present invention adopts a binary silicon-based oxide doping technology to modify a silicon oxide, and high-temperature stability of the silicon-based system is improved, thereby the high-temperature resistant 2 silicon-based aerogel material is obtained.

Further, the binary silicon-based oxide is aluminum silicate, mullite or zirconium silicate.

Further, tap density of the binary silicon-based oxide is less than 0.2 g/em?, an average pore size is less than 50 nm, and an indoor temperature heat conductivity is less than 0.04 W/m.K.

A preparation method for high-temperature resistant silicon-based aerogel powder, including the following steps: (1) after enabling water glass solution with 20%-30% of mass concentration to be mixed with water in a container according to a volume ratio of 1:1-2, forming mixed solution, after adding a dopant to the mixed solution, uniformly stirring, wherein the dopant is one or more of aluminum, zirconium and titanium metal inorganic salt, and a mass of the dopant is 0.05-0.1 times greater than a mass of the water glass solution, dropwise adding a hydrochloric acid to adjust a pH value of the mixed solution to be 2-4 in 2-4 drops/s of a speed, after adjusting, stirring for 20-30 min to form composite silicon-based sol, and adding absolute ethyl alcohol, wherein a volume ratio of the composite silicon-based sol and the absolute ethyl alcohol is 1:1-5, continuously stirring for 10-20 min, to obtain mixed glue; (2) dropwise adding ammonia water into the mixed glue in 2-4 drops/s of the speed and adjusting a pH value of the mixed glue to be 7-9, standing until the mixed glue is solidified, enabling the container to be heated for 20-50 min in 40-50 °C of a water bath, ageing, enabling the mixed glue in the container to form gel; (3) crushing the aged gel, washing for 1-2 h by using deionized water, suction-filtering, after suction-filtering, enabling a filter residue to be immerged in glycerinum and polyoxyethylene for replacement, wherein a mass ratio of the glycerinum and polyoxyethylene is 30-50:50-70, after stirring and washing for 20-40 min, suction-filtering, drying a filter residue after suction-filtering for 1-2 h in 60-80 °C under an ordinary pressure, to obtain silicon-based aerogel powder; conventional process and practical replacement liquid raw materials are n-hexane and ethanol, on the one hand, it is unsafe and not environmentally friendly, on the other hand, it needs to be replaced by two or three steps which are cumbersome, the workload is heavy, and the amount of sewage is large. (4) sintering the silicon-based aerogel powder for 1-2 h in 1200-2000 °C of a high temperature, to obtain high-temperature resistant silicon-based aerogel powder. 3

The beneficial effect of the present invention is as follows: compared with a traditional technology, the present invention has the following advantages:

1. The high-temperature resistant silicon-based aerogel powder in the present invention is a general-type material in the high-temperature heat-insulating field, is capable of solving a problem in the high-temperature heat-insulating field that a high-performance nano heat-insulating material is sparse extremely, and may be used for high-temperature industrial equipment of a high-temperature industrial furnace, a smelting furnace, a petrochemical cracking furnace and the like and materials of wood, steel and the like which need high-temperature fire-proof protection, application scenarios are very extensive, and a potential market value is huge.

Detailed Description of the Embodiments Embodiment 1: high-temperature resistant silicon-based aerogel powder includes the following substances in parts by mole: 1 mole part of a binary silicon-based oxide, and 2 mole parts of water glass, the binary silicon-based oxide is aluminum silicate, mullite or zirconium silicate, and tap density of the binary silicon-based oxide is less than 0.2 g/cm?, an average pore size is less than 50 nm, and an indoor temperature heat conductivity is less than 0.04 W/m.K.

Embodiment 2: high-temperature resistant silicon-based aerogel powder includes the following substances in parts by mole: 1.5 mole part of a binary silicon-based oxide, and 1 mole part of water glass, the binary silicon-based oxide is aluminum silicate, mullite or zirconium silicate, and tap density of the binary silicon-based oxide is less than 0.2 g/cm®, an average pore size is less than 50 nm, and an indoor temperature heat conductivity is less than 0.04 W/m.K.

Embodiment 3: high-temperature resistant silicon-based aerogel powder includes the following substances in parts by mole: 2 mole parts of a binary silicon-based oxide, and 1.5 mole parts of water glass, the binary silicon-based oxide is aluminum silicate, mullite or zirconium silicate, and tap density of the binary silicon-based oxide is less than 0.2 g/cm?, an average pore size is less than 50 nm, and an indoor temperature heat conductivity is less than 0.04 W/m. K.

Embodiment 4: a preparation method for high-temperature resistant silicon-based aerogel powder, including the following steps: (1) after enabling water glass solution with 20% of mass concentration to be 4 mixed with water in a container according to a volume ratio of 1:1, forming mixed solution, after adding a dopant to the mixed solution, uniformly stirring, herein the dopant is aluminum metal inorganic salt, and a mass of the dopant is 0.05 times greater than a mass of the water glass solution, dropwise adding a hydrochloric acid to adjust a pH value of the mixed solution to be 2 in 2-4 drops/s of a speed, after adjusting, stirring for 20 min to form composite silicon-based sol, and adding absolute ethyl alcohol, wherein a volume ratio of the composite silicon-based sol and the absolute ethyl alcohol is 1:1, continuously stirring for 10 min, to obtain mixed glue; (2) dropwise adding ammonia water into the mixed glue in 2-4 drops/s of the speed and adjusting a pH value of the mixed glue to be 7, standing until the mixed glue is solidified, enabling the container to be heated for 20 min in 40 °C of a water bath, ageing, enabling the mixed glue in the container to form gel; (3) crushing the aged gel, washing for 1 h by using deionized water, suction-filtering, after suction-filtering, enabling a filter residue to be immerged in glycerinum and polyoxyethylene for replacement, herein a mass ratio of the glycerinum and polyoxyethylene is 30:50, after stirring and washing for 20 min, suction-filtering, drying a filter residue after suction-filtering for 1 h in 60 °C under an ordinary pressure, to obtain silicon-based aerogel powder; and (4) sintering the silicon-based aerogel powder for 1 h in 1200 °C of a high temperature, to obtain high-temperature resistant silicon-based aerogel powder.

Embodiment 5: a preparation method for high-temperature resistant silicon-based aerogel powder, including the following steps: (1) after enabling water glass solution with 25% of mass concentration to be mixed with water in a container according to a volume ratio of 1:1.5, forming mixed solution, after adding a dopant to the mixed solution, uniformly stirring, herein the dopant is zirconium metal inorganic salt, and a mass of the dopant is 0.08 times greater than a mass of the water glass solution, dropwise adding a hydrochloric acid to adjust a pH value of the mixed solution to be 3 in 2-4 drops/s of a speed, after adjusting, stirring for 25 min to form composite silicon-based sol, and adding absolute ethyl alcohol, wherein a volume ratio of the composite silicon-based sol and the absolute ethyl alcohol is 1:3, continuously stirring for 15 min, to obtain mixed glue; (2) dropwise adding ammonia water into the mixed glue in 2-4 drops/s of the speed and adjusting a pH value of the mixed glue to be 8, standing until the mixed glue is solidified, enabling the container to be heated for 35 min in 45 C of a water 5 bath, ageing, enabling the mixed glue in the container to form gel; (3) crushing the aged gel, washing for 1.5 h by using deionized water, suction-filtering, after suction-filtering, enabling a filter residue to be immerged in glycerinum and polyoxyethylene for replacement, herein a mass ratio of the glycerinum and polyoxyethylene is 40:60, after stirring and washing for 30 min, suction-filtering, drying a filter residue after suction-filtering for 1.5 h in 70 °C under an ordinary pressure, to obtain silicon-based aerogel powder; and (4) sintering the silicon-based aerogel powder for 1.5 h in 1500 °C of a high temperature, to obtain high-temperature resistant silicon-based aerogel powder.

Embodiment 6: a preparation method for high-temperature resistant silicon-based aerogel powder, including the following steps: (1) after enabling water glass solution with 30% of mass concentration to be mixed with water in a container according to a volume ratio of 1:2, forming mixed solution, after adding a dopant to the mixed solution, uniformly stirring, herein the dopant is titanium metal inorganic salt, and a mass of the dopant is 0.1 times greater than a mass of the water glass solution, dropwise adding a hydrochloric acid to adjust a pH value of the mixed solution to be 4 in 2-4 drops/s of a speed, after adjusting, stirring for 30 min to form composite silicon-based sol, and adding absolute ethyl alcohol, wherein a volume ratio of the composite silicon-based sol and the absolute ethyl alcohol is 1:5, continuously stirring for 20 min, to obtain mixed glue; (2) dropwise adding ammonia water into the mixed glue in 2-4 drops/s of the speed and adjusting a pH value of the mixed glue to be 9, standing until the mixed glue is solidified, enabling the container to be heated for O min in O °C of a water bath, ageing, enabling the mixed glue in the container to form gel; (3) crushing the aged gel, washing for 2 h by using deionized water, suction-filtering, after suction-filtering, enabling a filter residue to be immerged in glycerinum and polyoxyethylene for replacement, herein a mass ratio of the glycerinum and polyoxyethylene is 50:70, after stirring and washing for 40 min, suction-filtering, drying a filter residue after suction-filtering for 2 h in 80 °C under an ordinary pressure, to obtain silicon-based aerogel powder; and (4) sintering the silicon-based aerogel powder for 2 h in 2000 °C of a high temperature, to obtain high-temperature resistant silicon-based aerogel powder.

Embodiment 7: a preparation method for high-temperature resistant silicon-based aerogel powder, including the following steps: 6

(1) after enabling water glass solution with 30% of mass concentration to be mixed with water in a container according to a volume ratio of 1:2, forming mixed solution, after adding a dopant to the mixed solution, uniformly stirring, herein the dopant is a mixture of two or three of aluminum, zirconium and titanium metal inorganic salt, and a mass of the dopant is 0.1 times greater than a mass of the water glass solution, dropwise adding a hydrochloric acid to adjust a pH value of the mixed solution to be 4 in 2-4 drops/s of a speed, after adjusting, stirring for 30 min to form composite silicon-based sol, and adding absolute ethyl alcohol, wherein a volume ratio of the composite silicon-based sol and the absolute ethyl alcohol is 1:5, continuously stirring for 20 min, to obtain mixed glue; (2) dropwise adding ammonia water into the mixed glue in 2-4 drops/s of the speed and adjusting a pH value of the mixed glue to be 9, standing until the mixed glue is solidified, enabling the container to be heated for 0 min in O °C of a water bath, ageing, enabling the mixed glue in the container to form gel; (3) crushing the aged gel, washing for 2 h by using deionized water, suction-filtering, after suction-filtering, enabling a filter residue to be immerged in glycerinum and polyoxyethylene for replacement, herein a mass ratio of the glycerinum and polyoxyethylene is 30:70, after stirring and washing for 40 min, suction-filtering, drying a filter residue after suction-filtering for 2 h in 80 °C under an ordinary pressure, to obtain silicon-based aerogel powder; and (4) sintering the silicon-based aerogel powder for 2 h in 2000 °C of a high temperature, to obtain high-temperature resistant silicon-based aerogel powder.

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Claims (4)

Conclusions A silicon-based heat-resistant airgel powder, wherein the silicon-based heat-resistant airgel powder comprises the following in parts per mole: 1 - 2 molar parts of a binary silicon-based oxide, and 1 - 2 molar parts of water glass. The silicon-based heat-resistant airgel powder of claim 1, wherein the binary silicon-based oxide is aluminum silicate, mullite or zirconium silicate. The silicon-based heat-resistant airgel powder of claim 1, wherein the bulk density of the silicon-based oxide aluminum silicate binary is less than 0.2 g/cm? , an average pore size is less than 50 nm, and an inner temperature heat conductivity is less than 0.04 W/m.K. 4. Preparation method for silicon-based heat-resistant airgel powder, comprising the following steps: (a) after allowing a water glass solution of 20% - 30% mass concentration to be mixed with water in a vessel at a volume ratio of 1:1-2, forming of a mixing solution, after adding a dopant to the mixing solution, stirring evenly, wherein the dopant is one or more metallic inorganic salts of aluminum, zirconium and titanium, and a mass of the dopant is 0.05 - 0.1 times greater then a mass of the water glass solution, dropwise addition of a hydrochloric acid to adjust the pH of the mixing solution to 2 - 4 at a rate of 2 - 4 drops/s, after adjustment, stir for 20 - 30 min to prepare a composite silicon-based sol, and addition of absolute ethyl alcohol, wherein a volume ratio of the composite silicon-based sol and of the absolute ethyl alcohol is 1 : 1-5, undefined stirring intermittently for 10 - 20 minutes to obtain a mixed adhesive; (b) dropwise addition of ammonia water to the mixed adhesive at a rate of 2 - 4 drops/s and adjusting the pH of the mixed adhesive to 7 - 9, allow to rest until the mixed adhesive has set, allow the vessel to warm up 8 in a water bath at 40-50°C for 20-50 min, age, allow the mixed glue to gel in the vessel; (c) grinding the aged gel, washing for 1 - 2 h with deionized water, suction filtration, after suction filtration, immersing a filter residue in glycinerinum and polyoxyethylene, giving a mass ratio of the glycerinum and the polyoxyethylene 30 - 50 : 50 - 70 is, after stirring and washing for 20-40 min, suction filtration, drying a filter residue after suction filtration for 1-2 hours at 60-80°C under an ordinary pressure, to obtain a silicon-based airgel powder; and (d) sintering the silicon-based airgel powder for 1-2 hours at a high temperature of 1200-2000°C to obtain a heat-resistant silicon-based airgel powder. 9