Aerogel-based harmful gas adsorption particles and preparation method thereof

Abstract

The present invention relates to an aerogel-based harmful gas adsorption particle and a preparation method thereof. The present invention compounded, modified and granulated a SiO2 aerogel with a high-porous structure with other functional materials under certain process conditions to obtain new adsorption particles with harmful gas adsorption and degradation functions of different specifications. The present invention prepares a highly porous SiO2 aerogel-based high-efficiency broad-spectrum harmful gas adsorption and degradation material. The product has the advantages of light weight, high adsorption efficiency and strong degradation ability, filling the gap in the industry and expanding the application field of SiO2 aerogel powder. The present invention is simple and flexible to operate, has relatively low requirements on equipment, has strong operability, and is easy to promote and apply in industrialization.

Description

Technical Field

[0001] The invention belongs to the technical field of novel aerogel preparation, and in particular relates to aerogel-based harmful gas adsorption particles and a preparation method thereof. Background Art

[0002] SiO 2 Aerogel has the characteristics of high porosity, large specific surface area, and strong nano-characteristics. The high porosity structure and high specific surface area give it super strong adsorption capacity. It has strong adsorption capacity for harmful gases such as aldehydes and benzene. It is a broad-spectrum multifunctional adsorption material.

[0003] In the past decade, many domestic research institutions and enterprises have been committed to SiO 2 Research and development, production and application of aerogel. After continuous research and development and production practice in recent years, SiO 2 The production and application technology of aerogel powder materials has become increasingly mature and has developed rapidly, and has had a revolutionary impact on related application industries. Many domestic companies are currently developing SiO 2 The technical development and production line construction of aerogel products have set off a wave of enthusiasm in the powder application industry. 2 The production technology of aerogel powder is becoming more and more mature, and its adsorption characteristics are remarkable, but its application in the air purification industry is still in the research and development stage, and there are relatively few mature and large-scale products. For the air purification or flue gas treatment industry, in order to facilitate application and achieve ideal results, powders need to be modified and granulated in many applications. Due to the low density and porous structure of aerogel powder, its characteristics are quite different from traditional powders, and traditional process methods cannot be used for modification and granulation. Therefore, in order to achieve efficient adsorption and degradation of harmful gases, it is necessary to solve the problem of SiO 2 The application of aerogel in the field of gas adsorption needs to be combined with its basic properties to determine the SiO 2 The modification and granulation process of aerogel is used to prepare aerogel-based harmful gas adsorption and degradation materials that can meet industrial applications. Summary of the invention

[0004] The purpose of the present invention is to transform highly porous SiO 2 Aerogel is compounded, modified and granulated with other functional materials to obtain new adsorption particles of different specifications with harmful gas adsorption and degradation functions.

[0005] The present invention is directed to SiO 2 The high porosity of aerogels and the demand for high-efficiency adsorption materials in related industries have led to a high demand for SiO 2Aerogel is compounded with other functional materials, modified and granulated. By blending powder materials with different pore structures and pore size distributions and selecting suitable catalysts, more efficient new adsorption material particles are obtained.

[0006] In order to solve the problems existing in the prior art, the present invention provides an aerogel-based harmful gas adsorption particle and a preparation method thereof, comprising the following components: SiO 2 5-20 parts of aerogel, 30-80 parts of porous silicate, 10-40 parts of binder, 0.5-2 parts of oxidant, and 0.1-0.5 parts of catalyst.

[0007] Preferably, the SiO 2 Aerogel index requirements: specific surface area ≥ 400m 2 / g, pore volume ≥ 0.8cm 3 / g, bulk density ≤0.06g / cm 3 , average pore size 15-40nm.

[0008] In any of the above schemes, it is preferred that the porous silicate is calcium silicate, zinc silicate, or aluminum magnesium silicate, and the index requirements are: specific surface area ≥ 600m 2 / g, pore volume ≥ 0.6cm 3 / g, average pore size 5-10nm, crystal water content 5-15%.

[0009] In any of the above schemes, it is preferred that the catalyst is an inorganic nano-powder material with photocatalytic performance, and the inorganic nano-powder material is any one of nano-carbon nitride and nano-cerium oxide.

[0010] In any of the above schemes, it is preferred that the oxidant is any one of potassium permanganate and sodium hypochlorite.

[0011] In any of the above schemes, it is preferred that the binder is hydrated calcium silicate which is an alkali-activated gelling material.

[0012] A method for preparing aerogel-based harmful gas adsorption particles, the preparation method comprising: first weighing an appropriate amount of SiO 2 Aerogel powder, porous silicate powder and catalyst powder are put into a wet granulator, and then fresh water is added to adjust the moisture content of the mixed powder to 30-50%, and mixed evenly. Then, an oxidant and a binder are added in sequence, and mixed evenly again before being used for product granulation.

[0013] Preferably, in a wet granulator, SiO 2Fresh water is added to the mixed powder of aerogel, porous silicate and catalyst, and the moisture content of the powder is adjusted to 30-50% (mass ratio). The materials are fully mixed in a mixer, and after mixing evenly, an oxidant (solid sodium hypochlorite powder or potassium permanganate solution with a mass concentration of 3-12%) and a binder hydrated calcium silicate are added in sequence, wherein the amount of the catalyst is 0.1-0.5% (to absolute dry SiO 2 aerogel and porous silicate powder), the amount of oxidant is 0.5-2% (for absolute dry SiO 2 aerogel and porous silicate powder), the amount of binder is 10-40% (for absolute dry SiO 2 aerogel and porous silicate powder).

[0014] The mixed materials are granulated by extrusion granulation equipment, and the extrusion granulation pressure is 1.0-1.5MPa. It includes: adding the prepared materials to the granulator, adjusting the extrusion granulation pressure according to the material properties and the requirements for the particle strength, and adjusting the particle size according to the application requirements. The prepared coarse particles are passed through an 80-mesh vibrating screen to remove the fine particles and dust, and obtain qualified new gas adsorption particles.

[0015] In order to achieve better technical effects and reduce drying costs, the sieved adsorption material particles in the present invention are dried by microwaves to remove moisture therein.

[0016] The present invention prepares a highly porous SiO 2 Aerogel-based high-efficiency broad-spectrum harmful gas adsorption and degradation materials, the product has the advantages of light weight, high adsorption efficiency, and strong degradation ability, filling the gap in the industry and expanding the SiO 2 The invention has the advantages of simple and flexible operation, relatively low equipment requirements, strong operability, and easy industrialization, promotion and application. DETAILED DESCRIPTION

[0017] In order to further understand the content of the present invention, the present invention will be described in detail below in conjunction with specific embodiments.

[0018] Example 1

[0019] The high-porous structure SiO 2 Aerogel index requirements: specific surface area 480m 2 / g, pore volume 0.88cm 3 / g, bulk density 0.051g / cm 3 , average pore diameter 23.9nm.

[0020] The porous silicate index requirements are: specific surface area 620m 2 / g, pore volume 0.65cm 3 / g, average pore size 5.9nm, crystal water content 11.3%. The preparation process of adsorption particles is as follows:

[0021] (1) Weigh SiO 2 5 kg of aerogel powder, 65 kg of porous silicate powder and 0.3 kg of catalyst nano-cerium oxide are added to the mixer, 40 kg of water is added, the mixer feed port is sealed, and the mixer is turned on;

[0022] (2) After the materials are evenly mixed, add 10 kg of potassium permanganate solution with a mass concentration of 8% and restart the mixer;

[0023] (3) After sufficient mixing, add 25 kg of hydrated calcium silicate as a binder to the material, turn on the mixer, and mix evenly;

[0024] (4) The mixed material is granulated on an extrusion granulator at a granulation pressure of 1.2 MPa;

[0025] (5) The prepared coarse particles are passed through an 80-mesh vibrating sieve to remove fine particles and dust;

[0026] (6) The screened particles are placed in an oven or microwave dryer for drying.

[0027] The aerogel-based adsorption particles prepared by this method are loose and porous, have a smooth surface, uniform particles, and good strength. The adsorption test results of the product are shown in Table 1.

[0028] Table 1 Adsorption test results

[0029]

[0030]

[0031] Example 2

[0032] The high-porous structure SiO 2 Aerogel index requirements: specific surface area 480m 2 / g, pore volume 0.88cm 3 / g, bulk density 0.051g / cm 3 , average pore diameter 23.9nm.

[0033] The porous silicate index requirements are: specific surface area 620m 2 / g, pore volume 0.65cm 3 / g, average pore size 5.9nm, crystal water content 11.3%. The preparation process of adsorption particles is as follows:

[0034] (1) Weigh SiO2 8 kg of aerogel powder, 62 kg of porous silicate powder and 0.3 kg of catalyst nano-cerium oxide were added to the mixer, 55 kg of water was added, the mixer feed port was sealed, and the mixer was turned on;

[0035] (2) After the materials are evenly mixed, add 10 kg of potassium permanganate solution with a mass concentration of 8% and restart the mixer;

[0036] (3) After sufficient mixing, add 25 kg of hydrated calcium silicate as a binder to the material, turn on the mixer, and mix evenly;

[0037] (4) The mixed material is granulated on an extrusion granulator at a granulation pressure of 1.2 MPa;

[0038] (5) The prepared coarse particles are passed through an 80-mesh vibrating sieve to remove fine particles and dust;

[0039] (6) The screened particles are placed in an oven or microwave dryer for drying.

[0040] The aerogel-based adsorption particles prepared by this method are loose and porous, have a smooth surface, uniform particles, and good strength. The adsorption test results of the product are shown in Table 2.

[0041] Table 2 Adsorption test results

[0042] Gas Type formaldehyde Toluene Xylene TVOC 3h cumulative adsorption percentage (%) 96 84 86 81

[0043] Example 3

[0044] The high-porous structure SiO 2 Aerogel index requirements: specific surface area 480m 2 / g, pore volume 0.88cm 3 / g, bulk density 0.051g / cm 3 , average pore diameter 23.9nm.

[0045] The porous silicate index requirements are: specific surface area 620m 2 / g, pore volume 0.65cm 3 / g, average pore size 5.9nm, crystal water content 11.3%. The preparation process of adsorption particles is as follows:

[0046] (1) Weigh SiO 2 10kg of aerogel powder, 60kg of porous silicate powder and 0.3kg of catalyst nano-cerium oxide are added to the mixer, 70kg of water is added, the mixer feed port is sealed, and the mixer is turned on;

[0047] (2) After the materials are evenly mixed, add 10 kg of potassium permanganate solution with a mass concentration of 8% and restart the mixer;

[0048] (3) After sufficient mixing, add 25 kg of hydrated calcium silicate as a binder to the material, turn on the mixer, and mix evenly;

[0049] (4) The mixed material is granulated on an extrusion granulator at a granulation pressure of 1.2 MPa;

[0050] (5) The prepared coarse particles are passed through an 80-mesh vibrating sieve to remove fine particles and dust;

[0051] (6) The screened particles are placed in an oven or microwave dryer for drying.

[0052] The aerogel-based adsorption particles prepared by this method are loose and porous, have a smooth surface, uniform particles, and good strength. The adsorption test results of the product are shown in Table 3.

[0053] Table 3 Adsorption test results

[0054] Gas Type formaldehyde Toluene Xylene TVOC 3h cumulative adsorption percentage (%) 98 85 88 82

[0055] It is not difficult for those skilled in the art to understand that the aerogel-based harmful gas adsorption particles and the preparation method thereof of the present invention include any combination of the parts shown in the invention content and the specific implementation method of the above-mentioned invention specification. Due to the limited space and to make the specification concise, the schemes composed of these combinations are not described one by one. Any modification, equivalent substitution, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for preparing aerogel-based harmful gas adsorbing particles, characterized in that: The preparation process is as follows: (1) Weigh 5 kg of SiO2 aerogel powder, 65 kg of porous silicate powder and 0.3 kg of catalyst nano-cerium oxide and add them to a mixer, add 40 kg of water, seal the mixer feed port, and start the mixer; (2) After the materials are evenly mixed, add 10 kg of potassium permanganate solution with a mass concentration of 8% and restart the mixer; (3) After sufficient mixing, add 25 kg of hydrated calcium silicate as a binder to the material, turn on the mixer, and mix evenly; (4) The mixed material is granulated on an extrusion granulator at a granulation pressure of 1.2 MPa; (5) The prepared coarse particles are passed through an 80-mesh vibrating sieve to remove fine particles and dust; (6) The screened particles are placed in an oven or microwave dryer for drying.

2. The method for preparing aerogel-based harmful gas adsorbing particles according to claim 1, characterized in that: The SiO2 aerogel index requirements are: specific surface area ≥ 400m 2 / g, pore volume ≥ 0.8cm 3 / g, bulk density ≤0.06g / cm 3 , average pore size 15-40nm.

3. The method for preparing aerogel-based harmful gas adsorbing particles according to claim 1, characterized in that: The porous silicate is calcium silicate, zinc silicate, or aluminum magnesium silicate, and the index requirements are: specific surface area ≥ 600m 2 / g, pore volume ≥ 0.6cm 3 / g, average pore size 5-10nm, crystal water content 5-15%.