Preparation method of aerogel thermal insulation material

Abstract

The invention discloses a preparation method of an aerogel thermal insulation material, which comprises the following steps: (1) uniformly mixing and stirring tetramethyl orthosilicate and ethanol to prepare a solution A; uniformly mixing and stirring ethanol and concentrated sulfuric acid to prepare a solution B; uniformly mixing and stirring the solution A and the solution B to obtain a precursor; (3) mixing and stirring ethanol, distilled water and the precursor, adding tetraethyl orthosilicate and an ammonia ethanol solution during stirring to obtain gel, and performing primary drying on the gel for aging; taking the aged gel, adding the aged gel into a hydrochloric acid ethanol solution and hexamethyldisilane, performing secondary drying for solvent exchange, and then performing tertiary drying for normal-pressure drying to obtain the aerogel. The silicon dioxide aerogel is successfully prepared by adopting a one-step synthesis method under normal pressure, the method has the characteristics of short process time, low solvent consumption, low energy consumption and the like, and the obtained silicon dioxide aerogel has good thermal stability, hydrophobicity and heat insulation property.

Description

Technical Field

[0001] The invention belongs to the field of multifunctional outdoor textile materials, and particularly relates to a method for preparing an aerogel thermal insulation material. Background Art

[0002] Aerogel refers to a solid material that is composed of continuous nanoparticles or polymer molecules that aggregate to form a nanoporous network structure, and the nanopores are filled with a gaseous dispersion medium. Silica (SiO2) aerogel is a lightweight porous non-metallic material composed of SiO2 particles with a three-dimensional nano-network structure. It is a nanoporous material with the characteristics of high porosity, low density and low thermal conductivity. It is widely used in thermal insulation, environmental purification, life medicine and other fields.

[0003] Silica aerogel is generally prepared by the sol-gel method, which includes hydrolyzing the silicon source in an organic solvent under the action of a catalyst, forming a three-dimensional network structure of silica wet gel through polycondensation, and then undergoing aging, surface modification, solvent replacement and drying processes to finally form silica aerogel. However, this method has the problems of long process time, high solvent usage, high energy consumption, etc., which increases cost expenditure and limits its industrial application and large-scale production. Summary of the invention

[0004] The purpose of the present invention is to provide a method for preparing an aerogel thermal insulation material. In view of the defects in the prior art, a one-step synthesis method is used to successfully prepare silica aerogel under normal pressure. The method has the characteristics of short process time, small amount of solvent used, low energy consumption, etc. The obtained silica aerogel has good thermal stability, hydrophobicity and thermal insulation.

[0005] In order to solve the above technical problems, the following technical solutions are adopted:

[0006] A method for preparing an aerogel thermal insulation material, characterized by comprising the following steps:

[0007] (1) Methyl orthosilicate and ethanol are mixed and stirred to obtain solution A; ethanol and concentrated sulfuric acid are mixed and stirred to obtain solution B;

[0008] (2) mixing solution A and solution B and stirring them uniformly to obtain solution C, adding distilled water to solution C after continuing to stir it to obtain a mixed solution, and continuing to stir the mixed solution to obtain a precursor;

[0009] (3) Mixing ethanol, distilled water and the precursor, adding tetraethyl orthosilicate and ammonia ethanol solution during stirring to obtain a gel, and drying the gel at 70-80° C. for 2 h for aging; taking the aged gel, adding hydrochloric acid ethanol solution and hexamethyldisilane, drying it for a second time at 90-100° C. for 1 h in a closed state for solvent exchange, and then drying it for a third time at 140-155° C. for 1 h in an open state for normal pressure drying to obtain an aerogel.

[0010] After optimization, in the step (1), the mass ratio of methyl orthosilicate to ethanol added to solution A is (3.6-4.5):1.

[0011] After optimization, in the step (1), the mass ratio of ethanol to concentrated sulfuric acid added to solution B is (180-195):1.

[0012] After optimization, in the step (2), the mixing mass ratio of solution A to solution B is (4.7-5.5):1.

[0013] After optimization, the solution B is divided into two portions and added to the solution A. After the first portion of solution B is added, it is stirred for 5 minutes and then the second portion of solution B is added, and stirring is continued until uniform. The mass ratio of the added amount of distilled water to the added methyl orthosilicate is 1: (20-30).

[0014] After optimization, in the step (3), the volume ratio of ethanol to the precursor is (1-1.5):1, the volume ratio of tetraethyl orthosilicate to the precursor is (1-1.6):1, and the volume ratio of ammonia ethanol to the precursor is 1:(10-15).

[0015] After optimization, the step (3) adopts a drying device to perform three drying operations, the drying device includes a loading platform, a unloading platform, a feeding mechanism, a drying mechanism, a rotating shift mechanism and a material basket, the material basket is used to store the material to be dried, the loading platform is used to place the material basket storing the material to be dried, the unloading platform is used to place the material basket storing the dried material, the drying mechanism includes a primary oven, a secondary oven and a tertiary oven, the primary oven is used to perform a primary drying operation, and its internal temperature is maintained at 70-80°C, the secondary oven is used to perform a secondary drying operation, and its internal temperature is maintained at 120-130°C, and the secondary oven is used to perform a secondary drying operation, and its internal temperature is maintained at 120-130°C. The temperature of the tertiary oven is maintained at 90-100°C, and the tertiary oven is used to perform tertiary drying operations, and its internal temperature is maintained at 140-155°C; the feeding mechanism is used to grab the material basket storing the material to be dried from the loading platform, and send it to the drying mechanism for drying. The feeding mechanism is also used to grab the material basket storing the dried material from the drying mechanism, and transport it to the unloading platform and send it out; the rotary shifting mechanism is used to drive the drying mechanism to rotate, thereby rotating the primary oven, the secondary oven or the tertiary oven to the loading and unloading station, and cooperating with the feeding mechanism to perform feeding and unloading actions.

[0016] After optimization, the feeding mechanism includes a feeding transverse movement module, a feeding lifting module, a manipulator bracket, a manipulator and a lifting guide assembly, the feeding transverse movement module is connected to the feeding lifting module, the feeding lifting module is connected to the manipulator bracket, the manipulator bracket is connected to the manipulator, the feeding transverse movement module is used to drive the manipulator to move transversely, and the feeding lifting module is used to drive the manipulator to move up and down; by driving the manipulator to move transversely and lift, the feeding and discharging of the material basket containing the materials can be realized; the lifting guide assembly includes a matching linear guide rail and a guide slide block, the linear guide rail is fixed to the feeding lifting module, and the guide slide block is connected to the manipulator bracket.

[0017] Preferably, the drying mechanism also includes a drying rack, and the drying rack is used to install the primary oven, the secondary oven and the tertiary oven; the rotating displacement mechanism includes a motor, a driving wheel, a driven wheel, a belt and a rotating spindle, the motor shaft of the motor is connected to the driving wheel, the driving wheel and the driven wheel are driven by the belt, the driven wheel is connected to and drives the rotating spindle, the rotating spindle is connected to the drying rack, and drives the drying rack to rotate, thereby adjusting the positions of the primary oven, the secondary oven and the tertiary oven to cooperate with the feeding mechanism.

[0018] Preferably, the primary oven, the secondary oven and the tertiary oven are all provided with a switch assembly, and the switch assembly includes an end cover, a switch screw module and an end cover track, the end cover is used to open or close the primary oven, the secondary oven and the tertiary oven, the switch screw module is used to drive the end cover to move, so as to control the end cover to be opened or closed, the end cover track is provided with a track groove, and pulleys are provided on both sides of the end cover, and the pulleys and the track grooves match each other.

[0019] The above technical solution has the following beneficial effects:

[0020] The present invention successfully prepares silica aerogel by a one-step synthesis method under normal pressure. The method has the characteristics of short process time, low solvent usage, low energy consumption, etc., which helps to control costs and is suitable for industrial applications and large-scale production. The silica aerogel prepared by the present invention is complete and stable, has uniform pore distribution, and has good thermal stability, hydrophobicity and thermal insulation. A certain amount of distilled water is added during the preparation of the precursor to control its water content, which helps to improve the thermal stability of the silica aerogel.

[0021] On the one hand, the drying device of the present invention realizes the automated feeding-drying-discharging operation, simplifies the operating procedures, improves work efficiency, and reduces the losses caused by improper human operation. The automated procedures can avoid human contact with the oven and prevent problems such as burns. On the other hand, primary drying, secondary drying and tertiary drying can be performed simultaneously, and multiple groups of preparation procedures can be performed simultaneously, which significantly improves the preparation efficiency and increases the aerogel output. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The present invention will be further described below in conjunction with the accompanying drawings:

[0023] Figure 1 It is a structural schematic diagram of the drying device.

[0024] Figure 2 It is a structural diagram of the feeding mechanism.

[0025] Figure 3 This is a schematic diagram of the structure of the robot.

[0026] Figure 4 It is a structural diagram of the material basket.

[0027] Figure 5 It is a structural schematic diagram of the loading platform.

[0028] Figure 6 It is a structural schematic diagram of the drying mechanism and the rotating displacement mechanism.

[0029] Figure 7 It is a structural schematic diagram of a primary oven.

[0030] The accompanying drawings are marked as follows: frame 1, loading platform 2, groove 21, material basket 3, basket bracket 31, feeding mechanism 4, feeding transverse movement module 41, feeding lifting module 42, manipulator bracket 43, manipulator 44, gripper 441, hook 442, guide slider 45, linear guide rail 46, box 5, drying mechanism 6, drying frame 61, primary oven 62, secondary oven 63, tertiary oven 64, end cover 621, switch screw module 622, end cover track 623, track groove 624, rotation shift mechanism 7, motor 71, driving wheel 72, belt 73, driven wheel 74, rotating spindle 75. DETAILED DESCRIPTION

[0031] The present invention aims to provide a method for preparing an aerogel thermal insulation material. During the preparation process, the water content of the precursor is controlled, and the silica aerogel is successfully prepared by a one-step synthesis method under normal pressure. The method has the characteristics of short process time, small amount of solvent used, low energy consumption, etc. The obtained silica aerogel has good thermal stability, hydrophobicity and thermal insulation.

[0032] The technical solution of the present invention is described in detail below in conjunction with specific embodiments:

[0033] Example 1

[0034] 40 parts of methyl orthosilicate and 10 parts of ethanol were mixed and stirred to obtain solution A; 10 parts of ethanol and 0.05 parts of concentrated sulfuric acid were mixed and stirred to obtain solution B; solution A and solution B were mixed and stirred to obtain solution C, and 2.0 parts of distilled water were added to solution C after continuous stirring to obtain a mixed solution, and the mixed solution was continuously stirred to obtain a precursor; 7L of ethanol, 0.5L of distilled water and 6L of precursor were mixed and stirred, and 7L of tetraethyl orthosilicate and 0.5L of ethanolamine solution (2mol / L) were added during stirring to obtain a gel, and the gel was dried once at 80°C for 2h for aging; the aged gel was added to 10L of ethanol hydrochloric acid solution (1mol / L) and 10L of hexamethyldisilane, and dried twice at 90°C for 1h in a closed state for solvent exchange, and then dried three times at 155°C for 1h in an open state for normal pressure drying to obtain an aerogel.

[0035] Example 2

[0036] 40 parts of methyl orthosilicate and 10 parts of ethanol were mixed and stirred to obtain solution A; 10 parts of ethanol and 0.05 parts of concentrated sulfuric acid were mixed and stirred to obtain solution B; solution A and solution B were mixed and stirred to obtain solution C, and 1.8 parts of distilled water were added to solution C after continuous stirring to obtain a mixed solution, and the mixed solution was continuously stirred to obtain a precursor; 7L of ethanol, 0.5L of distilled water and 6L of precursor were mixed and stirred, and 7L of tetraethyl orthosilicate and 0.5L of ethanolamine solution (2mol / L) were added during stirring to obtain a gel, and the gel was dried once at 80°C for 2h for aging; the aged gel was added to 10L of ethanol hydrochloric acid solution (1mol / L) and 10L of hexamethyldisilane, and dried twice at 90°C for 1h in a closed state for solvent exchange, and then dried three times at 155°C for 1h in an open state for normal pressure drying to obtain an aerogel.

[0037] Example 3

[0038] 40 parts of methyl orthosilicate and 10 parts of ethanol were mixed and stirred to obtain solution A; 10 parts of ethanol and 0.05 parts of concentrated sulfuric acid were mixed and stirred to obtain solution B; solution A and solution B were mixed and stirred to obtain solution C, and 1.6 parts of distilled water were added to solution C after continuous stirring to obtain a mixed solution, and the mixed solution was continuously stirred to obtain a precursor; 7L of ethanol, 0.5L of distilled water and 6L of precursor were mixed and stirred, and 7L of tetraethyl orthosilicate and 0.5L of ethanolamine solution (2mol / L) were added during stirring to obtain a gel, and the gel was dried once at 80°C for 2h for aging; the aged gel was added to 10L of ethanol hydrochloric acid solution (1mol / L) and 10L of hexamethyldisilane, and dried twice at 90°C for 1h in a closed state for solvent exchange, and then dried three times at 155°C for 1h in an open state for normal pressure drying to obtain an aerogel.

[0039] Example 4

[0040] 40 parts of methyl orthosilicate and 10 parts of ethanol were mixed and stirred to obtain solution A; 10 parts of ethanol and 0.05 parts of concentrated sulfuric acid were mixed and stirred to obtain solution B; solution A and solution B were mixed and stirred to obtain solution C, and 1.4 parts of distilled water were added to solution C after continuous stirring to obtain a mixed solution, and the mixed solution was continuously stirred to obtain a precursor; 7L of ethanol, 0.5L of distilled water and 6L of precursor were mixed and stirred, and 7L of tetraethyl orthosilicate and 0.5L of ethanolamine solution (2mol / L) were added during stirring to obtain a gel, and the gel was dried once at 80°C for 2h for aging; the aged gel was added to 10L of ethanol hydrochloric acid solution (1mol / L) and 10L of hexamethyldisilane, and dried twice at 90°C for 1h in a closed state for solvent exchange, and then dried three times at 155°C for 1h in an open state for normal pressure drying to obtain an aerogel.

[0041] Comparative Example 1

[0042] 40 parts of methyl orthosilicate and 10 parts of ethanol were mixed and stirred to obtain solution A; 10 parts of ethanol and 0.05 parts of concentrated sulfuric acid were mixed and stirred to obtain solution B; solution A and solution B were mixed and stirred to obtain solution C, and 1.0 parts of distilled water was added to solution C after continued stirring to obtain a mixed solution, and the mixed solution was continued to be stirred to obtain a precursor; 7L of ethanol, 0.5L of distilled water and 6L of precursor were mixed and stirred, and 7L of tetraethyl orthosilicate and 0.5L of ethanolic ammonia solution (2mol / L) were added during stirring to obtain a gel, and the gel was dried once at 80°C for 2h for aging; the aged gel was added to 10L of ethanolic hydrochloric acid solution (1mol / L) and 10L of hexamethyldisilane, and dried twice at 90°C for 1h in a closed state for solvent exchange, and then dried three times at 155°C for 1h in an open state for normal pressure drying to obtain an aerogel.

[0043] Examples 1-4 and control example 1 were subjected to thermal stability analysis using thermogravimetric / simultaneous differential thermal analysis. Control example 1 had the highest weight loss rate, losing 80% of its weight. This shows that the thermal stability of silica aerogel can be improved by controlling the water content of the precursor.

[0044] Example 5

[0045] In Examples 1 to 4, a drying device is used to perform three drying operations. The drying device includes a frame 1 and a loading platform 2, a unloading platform (not shown in the figure), a feeding mechanism 4, a drying mechanism 6, a rotating displacement mechanism 7 and a material basket 3 installed on the frame 1. The material basket 3 is used to store the gel material to be dried. The loading platform 2 is used to place the material basket 3 storing the material to be dried. A groove 21 is provided inside the loading platform. The material basket 3 is placed in the groove 21 to play a positioning role, so that the feeding mechanism 4 can accurately grab the material basket 3. The unloading platform is used to place the material basket 3 storing the dried material. After the feeding mechanism 4 grabs the dried material basket 3, it transports it and places it on the unloading platform, and the staff takes the dried material from the unloading platform.

[0046] The drying mechanism 6 is used to perform primary drying, secondary drying and tertiary drying on the material, and includes a drying rack 1 and a primary oven 62, a secondary oven 63 and a tertiary oven 64 installed on the drying rack 61. The primary oven 62 is used to perform a primary drying operation, and its drying temperature is set to 80°C and the drying time is 2h; the secondary oven 63 is used to perform a secondary drying operation, and its drying temperature is set to 90°C and the drying time is 1h; the tertiary oven 64 is used to perform a tertiary drying operation, and its drying temperature is set to 155°C and the drying time is 1h. The primary oven 62, the secondary oven 63 and the tertiary oven 64 are regularly arranged on the drying rack 61, and the connected interval angle is 120°, that is, the relative positions of the three ovens change once every 120° rotation.

[0047] The rotary shift mechanism 7 is used to drive the drying mechanism 6 to rotate, so as to achieve the purpose of adjusting the relative positions of the three ovens. The rotary shift mechanism 7 includes a motor 71, a driving wheel 72, a driven wheel 74, a belt 73 and a rotating spindle 75. The motor 71 shaft of the motor 71 is connected to the driving wheel 72, the driving wheel 72 and the driven wheel 74 are driven by the belt 73, the driven wheel 74 is connected and drives the rotating spindle 75, and the rotating spindle 75 penetrates and connects the drying frame 61, which is used to drive the drying frame 61 to rotate, so as to adjust the positions of the primary oven 62, the secondary oven 63 and the tertiary oven 64, and cooperate with the feeding mechanism 4. The position in the drying mechanism 6 that can cooperate with the feeding mechanism 4 is called the feeding and discharging station, and the purpose of the rotary drying mechanism 6 is to rotate the corresponding oven to the feeding and discharging station to achieve targeted feeding and discharging. The rotary shift mechanism 7 is designed to rotate at an angle of 120° or 240° each time, that is, after each rotation, the corresponding oven can accurately fall to the feeding and discharging station.

[0048] The primary oven 62, the secondary oven 63 and the tertiary oven 64 are all provided with a switch assembly, which is used to control the opening or closing of the oven. The switch assembly includes an end cover 621, a switch screw module 622 and an end cover track 623. The end cover 621 matches the structure of the oven opening and can seal the opening with good air tightness. The end cover track 623 is installed at the opening of each oven. Track grooves 624 are provided on both sides of the end cover track 623. The end cover 621 is installed in the end cover track 623. Pulleys (not marked in the figure) are provided on both sides. The pulleys on both sides are respectively installed in the track grooves 624 on both sides. Therefore, the end cover 621 can move forward and backward along the end cover track 623, and the oven can be opened or closed during the horizontal movement. The switch screw module 622 is connected to the end cover 621, and is used to control the front and rear transverse movement of the end cover 621, so as to achieve the purpose of controlling the opening or closing of the oven. The structure is cleverly designed to achieve the function of opening and closing the oven without contact, and can automatically complete the drying operation, and avoid problems such as burns caused by human contact with the oven. The oven can be fed and unloaded in the open state. In order to match the actual preparation process, the secondary oven 63 performs the drying operation in a closed state, and the tertiary oven 64 performs the drying operation in an open state.

[0049] The frame 1 includes a box body 5, the upper end of which is open, and a drying mechanism 6 is installed inside the box body 5, which serves the purpose of surrounding the drying mechanism 6 to prevent the drying mechanism 6 inside from being damaged and avoid burns caused by human contact with the oven.

[0050] The feeding mechanism 4 is used to grab the material basket 3 storing the material to be dried from the loading platform 2 and send it to the drying mechanism 6 for drying. The feeding mechanism 4 is also used to grab the material basket 3 storing the dried material from the drying mechanism 6, transport it to the unloading platform and send it out; the feeding mechanism 4 includes a feeding transverse movement module 41, a feeding lifting module 42, a manipulator bracket 43, a manipulator 44 and a lifting guide assembly. The feeding transverse movement module 41 is connected by a connecting piece and drives the feeding lifting module 42 to move transversely. The feeding lifting module 42 is a screw structure, which includes a screw motor, a transmission assembly and a screw. A screw seat is connected to the screw, and the screw seat is connected to the manipulator bracket 43. The manipulator bracket 43 is connected to the manipulator 44 downward, thereby driving the manipulator 44 to move up and down, and cooperating with the feeding transverse movement module 41 to achieve the purpose of driving the manipulator 44 to move transversely and lift. The manipulator 44 is provided with two groups, front and rear, each group of manipulators 44 includes two front and rear grippers 441, and each gripper 441 is provided with a hook 442 at the gripping position; the upper end of the material basket 3 is provided with a basket support 31, and the gripping position of the basket support 31 matches the hook 442, so that the manipulator 44 can firmly grip the basket support 31. When gripping, it is lowered to the gripping height in advance, and then moved horizontally for a short distance, so that the manipulator 44 is inserted into the basket support 31, and then the basket support 31 is raised and falls into the hook 442 of the manipulator 44, so that the material basket 3 can be firmly gripped.

[0051] The lifting guide assembly includes two sets of matching linear guide rails 46 and guide sliders 45. The two sets of linear guide rails 46 are respectively fixed on both sides of the feeding lifting module 42. The two sets of guide sliders are respectively connected to the left and right sides of the manipulator bracket 43. The linear guide rails 46 and the guide sliders 45 correspond one by one to guide the lifting and lowering action of the manipulator bracket 43, thereby improving stability and reducing the probability of failure.

[0052] The working process of the drying device is as follows:

[0053] 1. Take the dried material once, put it into the material basket 3, and then put the material basket 3 into the loading platform 2.

[0054] 2. The staff selects the primary oven 62, and the rotating shift mechanism 7 drives the drying mechanism 6 to rotate, and rotates the primary oven 62 to the loading and unloading position.

[0055] 3. The feeding mechanism 4 moves to the top of the loading platform 2, grabs the material basket 3 after the descending-transverse movement-ascending action, and then moves the material basket 3 transversely to the top of the loading and unloading station after grabbing. After the descending-transverse movement-ascending action, the material basket 3 is placed in the primary drying oven 62.

[0056] 4. Repeat steps 1-3, and the second-dried material and the third-dried material can be fed into the second drying oven 63 and the third drying oven 64.

[0057] 5. After the primary oven 62, the secondary oven 63 or the tertiary oven 64 completes the drying operation, a completion signal is generated, and the rotary shift mechanism 7 works to drive the drying mechanism 6 to rotate, and rotates the oven that has completed the drying operation to the loading and unloading station.

[0058] 6. The feeding mechanism 4 moves to the top of the feeding and unloading station, grabs the material basket 3 after the descending-lateral movement-ascending action, and then moves the material basket 3 horizontally to the top of the unloading platform after grabbing. After the descending-lateral movement-ascending action, the material basket 3 is placed on the unloading platform for delivery.

[0059] 7. Repeat steps 5-6 to send out the material basket 3 that has completed the drying operation.

[0060] On the one hand, the drying device of the present invention realizes the automated feeding-drying-discharging operation, simplifies the operating procedures, improves work efficiency, and reduces the losses caused by improper human operation. The automated procedures can avoid human contact with the oven and prevent problems such as burns. On the other hand, primary drying, secondary drying and tertiary drying can be performed simultaneously, and multiple groups of preparation procedures can be performed simultaneously, which significantly improves the preparation efficiency and increases the aerogel output.

[0061] The above are only specific embodiments of the present invention, but the technical features of the present invention are not limited thereto. Any simple changes, equivalent replacements or modifications made based on the present invention to solve basically the same technical problems and achieve basically the same technical effects are all included in the protection scope of the present invention.

Claims

1. A method for preparing an aerogel thermal insulation material, characterized in that The steps include: (1) Methyl orthosilicate and ethanol are mixed and stirred to obtain solution A; ethanol and concentrated sulfuric acid are mixed and stirred to obtain solution B; (2) mixing solution A and solution B and stirring them uniformly to obtain solution C, adding distilled water to solution C after continuing to stir it to obtain a mixed solution, and continuing to stir the mixed solution to obtain a precursor; (3) Mixing ethanol, distilled water and the precursor, adding tetraethyl orthosilicate and ammonia ethanol solution during stirring to obtain a gel, and drying the gel at 70-80° C. for 2 h for aging; taking the aged gel, adding hydrochloric acid ethanol solution and hexamethyldisilane, drying it for a second time at 90-100° C. for 1 h in a closed state for solvent exchange, and then drying it for a third time at 140-155° C. for 1 h in an open state for normal pressure drying to obtain an aerogel.

2. The method for preparing an aerogel thermal insulation material according to claim 1, characterized in that: In the step (1), the mass ratio of methyl orthosilicate to ethanol added to solution A is (3.6-4.5):

1.

3. The method for preparing an aerogel thermal insulation material according to claim 1, characterized in that: In the step (1), the mass ratio of ethanol to concentrated sulfuric acid added to solution B is (180-195):

1.

4. The method for preparing an aerogel thermal insulation material according to claim 1, characterized in that: In the step (2), the mixing mass ratio of solution A to solution B is (4.7-5.5):

1.

5. The method for preparing an aerogel thermal insulation material according to claim 1, characterized in that: The solution B is divided into two portions and added to the solution A. After the first portion of solution B is added, it is stirred for 5 minutes before the second portion of solution B is added and continued to be stirred until uniform. The mass ratio of the added amount of distilled water to the added methyl orthosilicate is 1:(20-30).

6. The method for preparing an aerogel thermal insulation material according to claim 1, characterized in that: In the step (3), the volume ratio of ethanol to the precursor is (1-1.5):1, the volume ratio of tetraethyl orthosilicate to the precursor is (1-1.6):1, and the volume ratio of ammonia ethanol to the precursor is 1:(10-15).

7. The method for preparing an aerogel thermal insulation material according to claim 1, characterized in that: In the step (3), a drying device is used to perform a three-stage drying operation. The drying device includes a loading platform, a unloading platform, a feeding mechanism, a drying mechanism, a rotating shifting mechanism, and a material basket. The material basket is used to store the material to be dried. The loading platform is used to place the material basket storing the material to be dried. The unloading platform is used to place the material basket storing the dried material. The drying mechanism includes a primary oven, a secondary oven, and a tertiary oven. The primary oven is used to perform a primary drying operation, and its internal temperature is maintained at 70-80°C. The secondary oven is used to perform a secondary drying operation, and its internal temperature is maintained at 90-100℃, the tertiary oven is used to perform tertiary drying operations, and its internal temperature is maintained at 140-155℃; the feeding mechanism is used to grab the material basket storing the material to be dried from the loading platform, and send it to the drying mechanism for drying. The feeding mechanism is also used to grab the material basket storing the dried material from the drying mechanism, and transport it to the unloading platform and send it out; the rotary shifting mechanism is used to drive the drying mechanism to rotate, thereby rotating the primary oven, the secondary oven or the tertiary oven to the loading and unloading station, and cooperating with the feeding mechanism to perform feeding and unloading actions.

8. The method for preparing an aerogel thermal insulation material according to claim 7, characterized in that: The feeding mechanism includes a feeding transverse movement module, a feeding lifting module, a manipulator bracket, a manipulator and a lifting guide assembly, the feeding transverse movement module is connected to the feeding lifting module, the feeding lifting module is connected to the manipulator bracket, the manipulator bracket is connected to the manipulator, the feeding transverse movement module is used to drive the manipulator to move transversely, and the feeding lifting module is used to drive the manipulator to move up and down; by driving the manipulator to move transversely and lift, the feeding and unloading of the material basket containing the materials can be realized; the lifting guide assembly includes a matching linear guide rail and a guide slider, the linear guide rail is fixed to the feeding lifting module, and the guide slider is connected to the manipulator bracket.

9. The method for preparing an aerogel thermal insulation material according to claim 7, characterized in that: The drying mechanism also includes a drying rack, and the drying rack is used to install the primary oven, the secondary oven and the tertiary oven; the rotating displacement mechanism includes a motor, a driving wheel, a driven wheel, a belt and a rotating spindle, the motor shaft of the motor is connected to the driving wheel, the driving wheel and the driven wheel are driven by the belt, the driven wheel is connected to and drives the rotating spindle, the rotating spindle is connected to the drying rack, and drives the drying rack to rotate, so as to adjust the positions of the primary oven, the secondary oven and the tertiary oven, and cooperate with the feeding mechanism.

10. The method for preparing an aerogel thermal insulation material according to claim 7, characterized in that: The primary oven, the secondary oven and the tertiary oven are all provided with a switch assembly, and the switch assembly includes an end cover, a switch screw module and an end cover track. The end cover is used to open or close the primary oven, the secondary oven and the tertiary oven. The switch screw module is used to drive the end cover to move, so as to control the end cover to open or close. The end cover track is provided with a track groove, and pulleys are provided on both sides of the end cover, and the pulleys and the track grooves match each other.

Images