High purity high modulus potassium silicate solution and method for making same

Abstract

The application discloses a kind of high-purity high-modulus potassium silicate solution and preparation method thereof, select the purity of not less than 99.95% potassium silicate powder, ensure that the high purity of the potassium silicate solution finally prepared, by electrolytic method preparation potassium silicate solution and adjust direct current power parameter, stirring rate, pH value and temperature and other factors, can realize the accurate control to reaction process, can control reaction rate and product quality, select electrolytic method and electromagnetic stirring combined method, it is suitable for large-scale production, can be prepared in relatively short time the high-modulus potassium silicate solution of modulus 5.5-8, the preparation process of the application is simple, low in cost, with higher stability, by accurate control parameter, can adjust solution property to meet the demand of multiple fields.

Description

Technical Field

[0001] This invention relates to the field of potassium silicate solution preparation technology, and in particular to a high-purity, high-modulus potassium silicate solution and its preparation method. Background Technology

[0002] High-modulus potassium silicate solution is an inorganic material with high hardness, high corrosion resistance, and high-temperature stability. A higher ratio of SiO2 to K2O results in a more compact network structure between potassium silicate molecules, strengthening chemical bonds and thus improving the surface hardness after coating. Furthermore, a higher modulus of potassium silicate solution indicates better chemical stability, thermal stability, and corrosion resistance. High-modulus potassium silicate solutions can withstand harsh environments such as strong acids and alkalis, high temperatures, and thermal shock.

[0003] High-modulus potassium silicate solution plays a vital role in the building materials industry. It can be used as an additive to improve the performance of cement and concrete, enhancing their strength and durability. Its high modulus makes cement and concrete stronger and more durable, resisting erosion from various external environmental factors. Furthermore, high-modulus potassium silicate solution is widely used in the ceramics and glass industries. It can be used as a sintering aid to improve the density and strength of ceramic and glass products, as well as their refractoriness and chemical stability. Another important application area for high-modulus potassium silicate solution is in water-based anti-corrosion coatings. Traditional solvent-based anti-corrosion coatings contain volatile organic compounds (VOCs), posing potential threats to the environment and human health. Water-based anti-corrosion coatings, with their advantages of being solvent-free and having low VOC emissions, are gradually replacing traditional coatings. High-modulus potassium silicate solution, as a key component of water-based anti-corrosion coatings, can be used as a thickener, binder, and reinforcing agent, improving the coating's adhesion, rheology, and durability. Meanwhile, due to its high modulus properties, potassium silicate solution can form a strong and durable coating, which can effectively protect the surface of the coated object from corrosion and oxidation. This enables water-based anti-corrosion coatings to be widely used in construction, shipbuilding, bridges and other fields, which is of great significance for improving the durability and safety of infrastructure.

[0004] Therefore, there is an urgent need to develop a method for preparing a high-purity, high-modulus potassium silicate solution to meet the above-mentioned application requirements. Summary of the Invention

[0005] To address the problems existing in the prior art, one of the objectives of this invention is to provide a high-purity, high-modulus potassium silicate solution and its preparation method.

[0006] Another object of the present invention is to provide a high-purity, high-modulus potassium silicate solution prepared by the above preparation method.

[0007] This invention is achieved by a method for preparing a high-purity, high-modulus potassium silicate solution, comprising the following steps:

[0008] S1. Weigh 125-625g of potassium silicate powder and 2.5-5.0L of deionized water for later use; add deionized water at 60±2℃ to a beaker and place a magnetic stir bar in the beaker; then slowly and evenly add the weighed potassium silicate powder to the beaker, and at the same time start the magnetic stir bar, set the stirring speed to 800-1500rpm, control the stirring temperature at 60±2℃, and stir for 3-6 hours until the potassium silicate powder is completely dissolved to obtain a potassium silicate solution;

[0009] S2. Detect the pH value of the potassium silicate solution obtained in step S1, and gradually add diluted acid or alkali to make the pH value of the potassium silicate solution reach 10-11.

[0010] S3. Insert the funnel into a clean polypropylene narrow-mouth bottle, then place a polypropylene filter with a pore size of 2.5μm into the funnel, ensuring that the polypropylene filter is evenly attached to the inner wall of the funnel; then pour the potassium silicate solution into the funnel and filter it to obtain a potassium silicate solution with a concentration of 0.5-1.0M / L.

[0011] S4. Select a glass electrolytic cell, a flat platinum anode, and a stainless steel cathode. Add the 0.5-1.0 M / L potassium silicate solution obtained in step S3 into the electrolytic cell and perform electrolysis, controlling the current density at 15-30 mA / cm². 2 The electrolysis time is 4-6 hours, and the electrolysis temperature is maintained at 70±2℃. During the electrolysis, 120-500g of nano silica powder is continuously and uniformly added over a period of 4-5 hours. A mechanical stirring device is used to stir the solution during the addition of the nano silica powder. Afterward, an automatic control system is used to continuously monitor and adjust the pH value of the solution to maintain it at 10-11.

[0012] S5. After electrolysis is complete, disconnect the power supply; then use a filter with a pore size of 0.2-0.45μm to filter the solution obtained in step S4 into a wide-mouth glass bottle to obtain a high-purity potassium silicate solution; then pour the high-purity potassium silicate solution into a polytetrafluoroethylene container to obtain a container containing the high-purity potassium silicate solution.

[0013] S6. Place the container containing the high-purity potassium silicate solution obtained in step S5 into the freezing chamber of a freeze dryer, adjust the temperature between -40℃ and -80℃, and freeze for 2-8 hours. After the solution is completely frozen into a solid state, start the vacuum equipment of the freeze dryer, gradually reduce the pressure in the freezing chamber, and periodically take samples to test the modulus of the potassium silicate solution during the vacuuming process. When the potassium silicate solution reaches the required concentration, stop the operation of the freeze dryer, turn off the vacuum equipment and other equipment, and remove the container from the freezing chamber to obtain the concentrated potassium silicate solution.

[0014] S7. Place the magnetic stir bar in a beaker, then add 200-500g of the concentrated potassium silicate solution obtained in step S6. Start the magnetic stir bar for initial stirring, setting the stirring speed to 800-1500 rpm, the stirring temperature to 60±2℃, and the stirring time to 3-6 hours. After the initial stirring, increase the stirring speed of the magnetic stir bar to 4000-4500 rpm. During stirring, continuously add 50-500mL of deionized water at 60±2℃ to the beaker to maintain a stable vortex state in the solution. Use an automatic control system to monitor and adjust the pH value to ensure that the pH value remains constant. The temperature is maintained between 10 and 11. Then, 100-800g of silica sol is added dropwise to a beaker, while 100-250ml of deionized water at 60±2℃ is added dropwise for the second time, along with 20-200g of methyltrimethoxysilane. After the methyltrimethoxysilane has been added, 15-30g of water-soluble organosilicon polymer resin is added to the beaker at a uniform rate, while 100-250ml of deionized water at 60±2℃ is added dropwise for the third time. After stirring for 2-3 hours, the potassium silicate solution becomes translucent, resulting in a high-purity, high-modulus potassium silicate solution with a modulus of 5.5-8.

[0015] Preferably, in step S1, the potassium silicate powder has a purity of not less than 99.95%, a modulus of 3.0-3.5, and a particle size between 5-15 μm.

[0016] Preferably, in step S1, the mass ratio of potassium silicate powder to deionized water in the potassium silicate solution is 1:8-20.

[0017] Preferably, in step S2, the concentration of the diluted acid or base is 0.1 M / L, the acid is hydrochloric acid, and the base is potassium hydroxide.

[0018] Preferably, in step S4, the purity of the nano-silica powder is 99.99% and the particle size is 20-80 nm.

[0019] Preferably, in step S4, the power source used for electrolysis is a DC power source.

[0020] Preferably, in step S4, the propeller in the mechanical stirring device is made of polytetrafluoroethylene (PTFE) and stainless steel, and the stirring speed of the propeller is controlled at 300-500 rpm; the automatic control system includes a pH sensor for monitoring the pH value of the solution, a feedback control device for controlling the amount of acid and alkali additives added, and an acid and alkali addition device for adding acid and alkali additives.

[0021] Preferably, in step S6, the vacuum equipment used by the freeze dryer is a mechanical pump and a diffusion pump, and the vacuuming time is controlled between 5 and 80 minutes.

[0022] Preferably, in step S7, the dripping time of silica sol, the second dripping of deionized water and methyltrimethoxysilane is controlled at 45-60 min; the dripping time of water-soluble organosilicon polymer resin and the third dripping of deionized water is controlled at 45-60 min.

[0023] Preferably, in step S7, the mass percentages of concentrated potassium silicate solution, silica sol, deionized water, methyltrimethoxysilane, and water-soluble organosilicon polymer resin in the total solution are 30-80%, 5.0-40%, 5.0-30%, 3.0-6.0%, and 0.5-1.5%, respectively.

[0024] The advantages and positive effects of this invention are:

[0025] (1) This invention discloses a method for preparing a high-modulus potassium silicate solution with a modulus of 5.5-8. The entire process comprehensively considers factors such as the purity, uniformity, and stability of the solution. The process is simple and has low manufacturing costs. Preparing potassium silicate solution by electrolysis allows for precise control of the reaction process, enabling control of the reaction rate and product quality. The overall controllability allows for better adjustment of the solution properties to meet specific needs. This invention uses a combination of electrolysis and electromagnetic stirring, which is suitable for large-scale production. It can prepare high-modulus potassium silicate solution in a relatively short time, has high production efficiency, and can meet the needs of industrial production.

[0026] (2) The present invention selects potassium silicate powder with a purity of not less than 99.95%, which ensures the high purity of the potassium silicate solution finally prepared.

[0027] (3) By adjusting the DC power supply parameters, stirring rate, pH value and temperature, the present invention can precisely control the properties of potassium silicate solution, such as pH value, modulus and concentration, so as to improve the controllability and consistency of the production process.

[0028] (4) The nano-silica powder used in this invention has a particle size between 20-80 nm, which allows for complete dissolution and reaction. This invention uses an electromagnetic stirrer for stirring, which can keep the solution in a stable eddy current state, promote mass transfer between the reactants and the electrodes, thereby achieving a uniform distribution of potassium silicate solution and nano-silica powder and avoiding local concentration differences.

[0029] (5) This invention uses freeze-drying technology, which can rapidly freeze and dehydrate at low temperatures, effectively preserving the active ingredients in the potassium silicate solution. Compared with traditional heating concentration methods, freeze-drying avoids the introduction of impurities and deposits that may exist in the traditional concentration process, increasing the stability and storage resistance of the solution.

[0030] (6) The high-modulus potassium silicate solution prepared by this invention has a higher gel / solution ratio, good thermal insulation properties, and electrical insulation properties. After coating, it exhibits higher mechanical properties and stability, and can be used to prepare thermal insulation materials, electronic packaging materials, and insulating layers. The high-modulus potassium silicate solution prepared by this invention has high viscosity and can form a system with good rheological properties. This gives it excellent wetting and adhesion properties in bonding, coating, and filling processes, enabling it to effectively adhere to various material surfaces and provide long-lasting protection. This allows it to be used in heat-resistant coatings, corrosion-resistant coatings, and high-temperature sealing materials. The high-modulus potassium silicate solution prepared by this invention can fill microscopic voids and cracks, thereby reducing or preventing the penetration of moisture, gas, and other substances. It can be applied in fields requiring improved waterproofing performance, such as underground construction and tunnel engineering. Detailed Implementation

[0031] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0032] Example 1

[0033] A method for preparing a high-purity, high-modulus potassium silicate solution includes the following steps:

[0034] S1. Weigh 150g of potassium silicate powder and 2.5L of deionized water at 60±2℃ for later use. The purity of the potassium silicate powder shall not be less than 99.95%, the modulus shall be 3.0-3.5, and the particle size of the potassium silicate powder shall be between 5-15μm. First, pour the deionized water into a beaker and place a magnetic stir bar in it. The beaker and magnetic stir bar shall be washed with deionized water beforehand and ensured to be clean and dust-free. Then, slowly and evenly add the weighed potassium silicate powder into the beaker, and at the same time start the magnetic stir bar, set the stirring speed to 1500rpm, control the stirring temperature at 60±2℃, and stir for 3h until the potassium silicate powder is completely dissolved to obtain a potassium silicate solution.

[0035] S2. Use a pH meter to detect the pH value of the potassium silicate solution obtained in step S1, and gradually add diluted acid (such as hydrochloric acid) or base (such as potassium hydroxide) to adjust the pH value of the potassium silicate solution to 10-11.

[0036] S3. Insert the funnel into a clean polypropylene (PP) narrow-mouth bottle, and then place a 2.5μm pore size polypropylene filter into the funnel, ensuring that the polypropylene filter is evenly attached to the inner wall of the funnel; then pour the potassium silicate solution into the funnel for filtration; collect the 0.5-1.0M / L potassium silicate solution obtained after filtration into a clean PP narrow-mouth bottle, seal it, and then place it in a fume hood for later use.

[0037] S4. Select a glass electrolytic cell, a flat platinum (Pt) anode, and a stainless steel cathode. Add the 0.5-1.0 M / L potassium silicate solution from the PP narrow-mouth bottle to the electrolytic cell for electrolysis. During electrolysis, adjust the DC power supply parameters to control the current density at 15-18 mA / cm². 2 Electrolysis was performed for 4 hours within the specified range, maintaining the electrolysis temperature at 70±2℃. During electrolysis, 300g of nano-silica powder was continuously and uniformly added over the 4 hours, and a mechanical stirrer was activated at a speed of 500rpm to increase the electrolysis rate and promote mass transfer between the reactants and electrodes. This ensured that potassium silicate and other substances in the solution were evenly distributed throughout the electrolytic cell, avoiding uneven electrolysis caused by local concentration differences. Then, an automatic control system continuously monitored and adjusted the pH of the solution. During adjustment, the amount of acid-base additives added was automatically adjusted according to the set value, and the pH of the solution was controlled in real time to maintain it between 10 and 11.

[0038] S5. After electrolysis is complete, disconnect the power supply to terminate the electrolysis process; then use a sterile capillary filter with a pore size of 0.45μm to filter the solution obtained in step S4 into a wide-mouth glass bottle to remove insoluble impurities and suspended solids, and obtain a high-purity potassium silicate solution; then pour the high-purity potassium silicate solution into a polytetrafluoroethylene container to obtain a container containing the high-purity potassium silicate solution.

[0039] S6. Place the container containing the high-purity potassium silicate solution in the freezer chamber of the freeze dryer. In the freezer chamber, adjust the temperature to -80℃ and freeze for 4 hours. After the solution is completely frozen into a solid state, start the vacuum equipment of the freeze dryer and gradually reduce the pressure in the freezer chamber to promote the sublimation process of the ice. After vacuuming for 30 minutes, stop the operation of the freeze dryer, turn off the vacuum equipment and other equipment, and remove the container from the freezer chamber to obtain the concentrated potassium silicate solution.

[0040] S7. Place the magnetic stir bar in the beaker, then add 250g of concentrated potassium silicate solution to the beaker. Start the magnetic stir bar for initial stirring, setting the stirring speed to 1500rpm and controlling the stirring temperature to 60±2℃ for 2 hours. After the initial stirring is completed, adjust the stirring speed of the magnetic stir bar to 4000rpm, and continuously add 200mL of deionized water at 60±2℃ to the beaker to keep the solution in a stable vortex state. Use the automatic control system to monitor and adjust the pH value to keep the pH value between 10 and 11.

[0041] Subsequently, 300g of silica sol was added dropwise to a beaker over a period of 60 minutes. During the addition, the solution in the beaker gradually thickened as the amount of silica sol added increased. Simultaneously, 200ml of deionized water at 60±2℃ was added dropwise to the beaker at a uniform rate to improve the fluidity of the solution and maintain a vortex state. At the same time, 80g of methyltrimethoxysilane was added. After the addition of methyltrimethoxysilane was completed, 15g of water-soluble organosilicon polymer resin and 200ml of deionized water at 60±2℃ were added dropwise to the beaker at a uniform rate over a period of 60 minutes. After stirring with a magnetic stirrer for 3 hours, a semi-transparent potassium silicate solution was obtained. The modulus of the potassium silicate solution was measured, and then the solution was sealed in a PP sealed container to obtain a high-purity, high-modulus potassium silicate solution.

[0042] The specific method for determining the modulus of potassium silicate solution is as follows:

[0043] Add 100 mL of deionized water at 60°C to a beaker. Then, using a pipette, take 2 mL of potassium silicate solution from a PP sealed container and add it dropwise to the beaker. Stir thoroughly with a glass rod until dissolved. Add 500 μL of methyl red indicator (0.0061 M ethanol solution) and 100 μL of malachite green indicator (0.0041 M), and let stand for 5 min. Next, add 0.5 M hydrochloric acid dropwise to the beaker. After the solution changes from green to purple-red, record the volume of hydrochloric acid added as V1 = 3.85 mL. Add 60 mL of 1.91 M sodium fluoride solution to the solution and stir with a glass rod for 2 min. When the solution changes from purple-red to green, add 0.1 M hydrochloric acid dropwise to the beaker. After the solution turns purple-red, continue adding 2 mL of hydrochloric acid dropwise, recording the volume of hydrochloric acid added as V2 = 53.5 mL. Let stand for 5 min. Next, add 0.5M sodium hydroxide to the beaker. When the solution turns bright green, record the amount of sodium hydroxide added as V3 = 11.8 ml.

[0044] The modulus (N) of the potassium silicate solution is calculated using the following formula: N = [(V2 - V3) / V1] × 0.50. The calculated modulus of the potassium silicate solution is 5.5. The modulus is recorded on a label and then affixed to the sealed container.

[0045] Place the viscometer on a level and stable platform, ensuring the rotating disk, blades, or tubing are clean and dust-free. Then, zero the instrument and calibrate parameters such as scribing speed and temperature. Use a sampler to take 300 ml of a potassium silicate solution with a modulus of 5.5 and pour it into the viscometer's sample cell, ensuring there are no air bubbles and closing the viscometer's cap. Start the viscometer at room temperature, setting the rotation speed to 300 rpm and the test time to 100 s. After three tests, average the results to obtain a viscosity of 12.44 Pa·s for the potassium silicate solution with a modulus of 5.5.

[0046] Example 2

[0047] A method for preparing a high-purity, high-modulus potassium silicate solution includes the following steps:

[0048] S1. Weigh 300g of potassium silicate powder and 4.0L of deionized water at 60±2℃ for later use. The purity of the potassium silicate powder shall not be less than 99.95%, the modulus shall be 3.0-3.5, and the particle size of the potassium silicate powder shall be between 5-15μm. First, pour the deionized water into a beaker and place a magnetic stir bar in it. The beaker and magnetic stir bar shall be washed with deionized water beforehand and ensured to be clean and dust-free. Then, slowly and evenly add the weighed potassium silicate powder into the beaker, and at the same time start the magnetic stir bar. Set the stirring speed to 1500rpm, control the stirring temperature at 60±2℃, and stir for 3 hours until the potassium silicate powder is completely dissolved to obtain a potassium silicate solution.

[0049] S2, same as step S2 in Example 1.

[0050] S3, same as step S3 in Example 1.

[0051] S4. Select a glass electrolytic cell, a flat platinum (Pt) anode, and a stainless steel cathode. Add the 0.5-1.0 M / L potassium silicate solution from the PP narrow-mouth bottle to the electrolytic cell for electrolysis. During electrolysis, adjust the DC power supply parameters to control the current density at 15-18 mA / cm². 2 Electrolysis was performed for 6 hours within the specified range, maintaining the electrolysis temperature at 70±2℃. During electrolysis, 400g of nano-silica powder was continuously and uniformly added over 4 hours, and a mechanical stirrer was activated at a speed of 500rpm to increase the electrolysis rate and promote mass transfer between the reactants and electrodes. This ensured that potassium silicate and other substances in the solution were evenly distributed throughout the electrolytic cell, avoiding uneven electrolysis caused by local concentration differences. Then, an automatic control system continuously monitored and adjusted the pH of the solution. During adjustment, the amount of acid-base additives added was automatically adjusted according to the set value, and the pH of the solution was controlled in real time to maintain it between 10 and 11.

[0052] S5. After electrolysis is complete, disconnect the power supply to terminate the electrolysis process; then use a sterile capillary filter with a pore size of 0.3 μm to filter the solution obtained in step S4 into a wide-mouth glass bottle to remove insoluble impurities and suspended solids, and obtain a high-purity potassium silicate solution; then pour the high-purity potassium silicate solution into a polytetrafluoroethylene container to obtain a container containing the high-purity potassium silicate solution.

[0053] S6. Place the container containing the high-purity potassium silicate solution in the freezer chamber of the freeze dryer. In the freezer chamber, adjust the temperature to -60℃ and freeze for 5 hours. After the solution is completely frozen into a solid state, start the vacuum equipment of the freeze dryer and gradually reduce the pressure in the freezer chamber to promote the sublimation process of the ice. After vacuuming for 20 minutes, stop the operation of the freeze dryer, turn off the vacuum equipment and other equipment, and remove the container from the freezer chamber to obtain the concentrated potassium silicate solution.

[0054] S7. Place the magnetic stir bar in the beaker, then add 300g of concentrated potassium silicate solution to the beaker. Start the magnetic stir bar for initial stirring, setting the stirring speed to 1200rpm and controlling the stirring temperature to 60±2℃ for 3 hours. After the initial stirring is completed, adjust the stirring speed of the magnetic stir bar to 4500rpm, and continuously add 200mL of deionized water at 60±2℃ to the beaker to keep the solution in a stable vortex state. Use the automatic control system to monitor and adjust the pH value to keep the pH value between 10 and 11.

[0055] Subsequently, 400g of silica sol was added dropwise to a beaker over a period of 60 minutes. During the dropwise addition, the solution in the beaker gradually thickened as the amount of silica sol added increased. Simultaneously, 300ml of deionized water at 60±2℃ was added dropwise to the beaker at a uniform rate to improve the fluidity of the solution and maintain a vortex state. At the same time, 120g of methyltrimethoxysilane was added. After the methyltrimethoxysilane was added, 20g of water-soluble organosilicon polymer resin and 300ml of deionized water at 60±2℃ were added dropwise to the beaker at a uniform rate over a period of 60 minutes. After stirring with a magnetic stirrer for 3 hours, a semi-transparent potassium silicate solution was obtained. The modulus of the potassium silicate solution was measured, and then the solution was sealed in a PP sealed container to obtain a high-purity, high-modulus potassium silicate solution.

[0056] The specific method for determining the modulus of potassium silicate solution is as follows:

[0057] Add 100 mL of deionized water at 60 °C to a beaker. Then, using a pipette, take 2 mL of potassium silicate solution from a PP sealed container and add it dropwise to the beaker. Stir thoroughly with a glass rod until dissolved. Add 500 μL of methyl red indicator (0.0061 M ethanol solution) and 100 μL of malachite green indicator (0.0041 M), and let stand for 5 min. Next, add 0.5 M hydrochloric acid dropwise to the beaker. After the solution changes from green to purple-red, record the volume of hydrochloric acid added as V1 = 3.0 mL. Add 60 mL of 1.91 M sodium fluoride solution to the solution and stir with a glass rod for 2 min. When the solution changes from purple-red to green, add 0.1 M hydrochloric acid dropwise to the beaker. After the solution turns purple-red, continue adding 2 mL of hydrochloric acid dropwise, recording the volume of hydrochloric acid added as V2 = 43.3 mL. Let stand for 5 min. Next, add 0.5M sodium hydroxide to the beaker. When the solution turns bright green, record the amount of sodium hydroxide added as V3 = 5.2 ml.

[0058] The modulus (N) of the potassium silicate solution is calculated using the following formula: N = [(V2 - V3) / V1] × 0.50. The calculated modulus of the potassium silicate solution is 6.3. The modulus is recorded on a label and then affixed to the sealed container.

[0059] Place the viscometer on a level and stable platform, ensuring the rotating disk, blades, or tubing are clean and dust-free. Then, zero the instrument and calibrate parameters such as scribing speed and temperature. Use a sampler to take 300 ml of a potassium silicate solution with a modulus of 6.3 and pour it into the viscometer's sample cell, ensuring there are no air bubbles and closing the viscometer's cap. Start the viscometer at room temperature, setting the rotation speed to 300 rpm and the test time to 100 s. After three tests, average the results to obtain a viscosity of 14.58 Pa·s for the potassium silicate solution with a modulus of 6.3.

[0060] Example 3

[0061] S1. Weigh 350g of potassium silicate powder and 5.0L of deionized water at 60±2℃. The potassium silicate powder should have a purity of not less than 99.95%, a modulus of 3.0-3.5, and a particle size between 5-15μm. First, pour the deionized water into a beaker and place a magnetic stir bar inside. The beaker and magnetic stir bar should be thoroughly cleaned with deionized water beforehand to ensure they are dust-free. Then, slowly and evenly add the weighed potassium silicate powder into the beaker while simultaneously starting the magnetic stirrer at a speed of 1500rpm. Maintain the stirring temperature at 60±2℃ and the stirring time for 3 hours until the potassium silicate powder is completely dissolved, yielding a potassium silicate solution.

[0062] S2, same as step S2 in Example 1.

[0063] S3, same as step S3 in Example 1.

[0064] S4. Select a glass electrolytic cell, a flat platinum (Pt) anode, and a stainless steel cathode. Add the 0.5-1.0 M / L potassium silicate solution from the PP narrow-mouth bottle to the electrolytic cell for electrolysis. During electrolysis, adjust the DC power supply parameters to control the current density at 15-18 mA / cm². 2 Electrolysis was performed for 6 hours within the specified range, maintaining the electrolysis temperature at 70±2℃. During electrolysis, 500g of nano-silica powder was continuously and uniformly added over 4 hours, and a mechanical stirrer was activated at a speed of 500rpm to increase the electrolysis rate and promote mass transfer between the reactants and electrodes. This ensured that potassium silicate and other substances in the solution were evenly distributed throughout the electrolytic cell, avoiding uneven electrolysis caused by local concentration differences. Then, an automatic control system continuously monitored and adjusted the pH of the solution. During adjustment, the amount of acid-base additives added was automatically adjusted according to the set value, and the pH of the solution was controlled in real time to maintain it between 10 and 11.

[0065] S5. After electrolysis is complete, disconnect the power supply to terminate the electrolysis process; then use a sterile capillary filter with a pore size of 0.25 μm to filter the solution obtained in step S4 into a wide-mouth glass bottle to remove insoluble impurities and suspended solids, and obtain a high-purity potassium silicate solution; then pour the high-purity potassium silicate solution into a polytetrafluoroethylene container to obtain a container containing the high-purity potassium silicate solution.

[0066] S6. Place the container containing the high-purity potassium silicate solution in the freezer chamber of the freeze dryer. In the freezer chamber, adjust the temperature to -40℃ and freeze for 6 hours. After the solution is completely frozen into a solid state, start the vacuum equipment of the freeze dryer and gradually reduce the pressure in the freezer chamber to promote the sublimation process of the ice. After evacuating the vacuum for 15 minutes, stop the operation of the freeze dryer, turn off the vacuum equipment and other equipment, and remove the container from the freezer chamber to obtain the concentrated potassium silicate solution.

[0067] S7. Place the magnetic stir bar in the beaker, then add 500g of concentrated potassium silicate solution to the beaker. Start the magnetic stir bar for initial stirring, setting the stirring speed to 800rpm and controlling the stirring temperature to 60±2℃ for 4 hours. After the initial stirring is completed, adjust the stirring speed of the magnetic stir bar to 4500rpm, and continuously add 200mL of deionized water at 60±2℃ to the beaker to keep the solution in a stable vortex state. Use the automatic control system to monitor and adjust the pH value to keep the pH value between 10 and 11.

[0068] Subsequently, 400g of silica sol was added dropwise to a beaker over a 60-minute period. During this time, the solution in the beaker gradually thickened as the amount of silica sol added increased. Simultaneously, 300ml of deionized water at 60±2℃ was added dropwise at a uniform rate to improve the solution's fluidity and maintain a vortex state. At the same time, 150g of methyltrimethoxysilane was added. After the methyltrimethoxysilane addition was complete, 25g of water-soluble organosilicon polymer resin and 300ml of deionized water at 60±2℃ were added dropwise at a uniform rate over another 60-minute period. After stirring with a magnetic stirrer for 3 hours, a semi-transparent potassium silicate solution was obtained. The modulus of the potassium silicate solution was measured, and then the solution was sealed in a PP container to obtain a high-purity, high-modulus potassium silicate solution.

[0069] The specific method for determining the modulus of potassium silicate solution is as follows:

[0070] Add 100 mL of deionized water at 60 °C to a beaker. Then, using a pipette, take 2 mL of potassium silicate solution from a PP sealed container and add it dropwise to the beaker. Stir thoroughly with a glass rod until dissolved. Next, add 500 μL of methyl red indicator (0.0061 M ethanol solution) and 100 μL of malachite green indicator (0.0041 M), and let stand for 5 min. Then, add 0.5 M hydrochloric acid dropwise to the beaker. After the solution changes from green to purple-red, record the volume of hydrochloric acid added as V1 = 2.75 mL. Next, add 60 mL of 1.91 M sodium fluoride solution to the solution and stir with a glass rod for 2 min. When the solution changes from purple-red to green, add 0.1 M hydrochloric acid dropwise to the beaker. After the solution turns purple-red, continue adding 2 mL of hydrochloric acid dropwise, recording the volume of hydrochloric acid added as V2 = 49.8 mL, and let stand for 5 min. Next, add 0.5M sodium hydroxide dropwise into the beaker. When the solution turns bright green, record the amount of sodium hydroxide added as V3 = 5.7 ml.

[0071] The modulus (N) of the potassium silicate solution is calculated using the following formula: N = [(V2 - V3) / V1] × 0.50. The calculated modulus of the potassium silicate solution is 8.0. After recording the modulus on a label, it is pasted on the sealed container.

[0072] Place the viscometer on a level and stable platform, ensuring the rotating disk, blades, or tubing are clean and dust-free. Then, zero the instrument and calibrate parameters such as scribing speed and temperature. Use a sampler to take 300 ml of a potassium silicate solution with a modulus of 8.0 and pour it into the viscometer's sample cell, ensuring there are no air bubbles and closing the viscometer's cap. Start the viscometer at room temperature, setting the rotation speed to 300 rpm and the test time to 100 s. After three tests, average the results to obtain a viscosity of 21.23 Pa·s for the potassium silicate solution with a modulus of 8.0.

[0073] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for producing a high-purity high-modulus potassium silicate solution, characterized by, The method comprises the following steps: S1, weigh 125-625g of potassium silicate powder and 2.5-5.0L of deionized water as standby, the purity of the potassium silicate powder is not less than 99.95%; add deionized water of 60±2℃ into a beaker, and put a magnetic stirrer into the beaker; then slowly and uniformly add the weighed potassium silicate powder into the beaker, start the magnetic stirrer at the same time, set the stirring speed to 800-1500rpm, control the stirring temperature to 60±2℃, and the stirring time is 3-6h, until the potassium silicate powder is completely dissolved, to obtain a potassium silicate solution; S2, detect the pH value of the potassium silicate solution obtained in step S1, gradually add diluted acid or base to make the pH value of the potassium silicate solution reach 10-11; S3, embed a funnel into a clean polypropylene narrow-mouth bottle, then put a polypropylene filter with a pore size of 2.5μm into the funnel, and ensure that the polypropylene filter is uniformly attached to the inner wall of the funnel; then pour the potassium silicate solution into the funnel for filtration treatment, to obtain a potassium silicate solution with a concentration of 0.5-1.0M / L; S4, using glass material electrolytic cell, flat platinum anode material and stainless steel cathode material, the 0.5-1.0M / L potassium silicate solution obtained in step S3 is added into the electrolytic cell, electrolysis is carried out, the current density is controlled at 15-30mA / cm 2 , the electrolysis time is 4-6h, and the electrolysis temperature is kept at 70±2℃; during electrolysis, 120-500g of nano-silicon dioxide powder with purity of 99.99% and particle size of 20-80nm is continuously added at a uniform speed, the adding time is controlled at 4-5h, and a mechanical stirring device is used for stirring during the adding of nano-silicon dioxide powder; then an automatic control system is used for continuously monitoring and adjusting the pH value of the solution, so that the pH value of the solution is kept at 10-11; S5, after electrolysis, disconnect the power supply; then use a filter with a pore size of 0.2-0.45μm to filter the solution obtained in step S4 into a glass wide-mouth bottle, to obtain a high-purity potassium silicate solution; then pour the high-purity potassium silicate solution into a polytetrafluoroethylene container, to obtain a container containing the high-purity potassium silicate solution; S6, place the container containing the high-purity potassium silicate solution obtained in step S5 in the freezing chamber of a freeze dryer, adjust the temperature to-40℃ to-80℃, and the freezing time is 2-8h; when the solution is completely frozen into a solid state, start the vacuum equipment of the freeze dryer, gradually reduce the pressure in the freezing chamber, and during the vacuumizing period, periodically take samples to detect the modulus of the potassium silicate solution, when the potassium silicate solution reaches the required concentration, stop the operation of the freeze dryer, close the vacuum equipment and other equipment, take out the container from the freezing chamber, to obtain a concentrated potassium silicate solution; S7, the magnetic stirrer is placed in the beaker, then 200-500g of concentrated potassium silicate solution obtained in step S6 is added into the beaker, the magnetic stirrer is started to perform primary stirring, the stirring rate is set to 800-1500rpm, the stirring temperature is 60±2℃, and the stirring time is 3-6h; after the primary stirring is completed, the stirring rate of the magnetic stirrer is increased to 4000-4500rpm, during the stirring, 50-500mL of deionized water at 60±2℃ is continuously added into the beaker to make the solution in a stable vortex state, and an automatic control system is used to monitor and adjust the pH value, so that the pH value is always kept between 10-11; then 100-800g of silica sol is added into the beaker, at the same time, 100-250ml of deionized water at 60±2℃ is secondly added into the beaker, and 20-200g of methyltrimethoxysilane is added; after the methyltrimethoxysilane is added, 15-30g of water-soluble silicone polymer resin is continuously added into the beaker at a uniform speed, at the same time, 100-250ml of deionized water at 60±2℃ is thirdly added into the beaker, after stirring for 2-3h, the potassium silicate solution becomes translucent, and high-purity high-modulus potassium silicate solution with a modulus of 5.5-8 is obtained.

2. The method for preparing high-purity, high-modulus potassium silicate solution according to claim 1, characterized in that: In step S1, the modulus of the potassium silicate powder is 3.0-3.5, and the particle size of the potassium silicate powder is between 5-15μm. In the potassium silicate solution, the mass ratio of the potassium silicate powder to the deionized water is 1:8-20.

3. The method for preparing high-purity, high-modulus potassium silicate solution according to claim 1, characterized in that: In step S2, the concentration of the diluted acid or base is 0.1M / L, the acid is hydrochloric acid, and the base is potassium hydroxide.

4. The method for preparing high-purity, high-modulus potassium silicate solution according to claim 1, characterized in that: In step S4, the power source used for electrolysis is a direct current power source.

5. The process for the preparation of high purity high modulus potassium silicate solution as claimed in claim 1 wherein: In step S4, in the mechanical stirring device, the propeller is made of polytetrafluoroethylene (PTFE) and stainless steel, and the stirring rate of the propeller is controlled at 300-500rpm; the automatic control system includes a pH sensor for monitoring the pH value of the solution, a feedback control device for controlling the addition amount of the acid-base additive, and an acid-base adding device for adding the acid-base additive.

6. The method for preparing high-purity, high-modulus potassium silicate solution according to claim 1, characterized in that: In step S6, the vacuum equipment of the freeze dryer is a mechanical pump and a diffusion pump, and the vacuum time is controlled at 5-80min.

7. The method for preparing high-purity, high-modulus potassium silicate solution according to claim 1, characterized in that: In step S7, the dropping time of the silica sol, the secondly added deionized water and the methyltrimethoxysilane is controlled at 45-60min respectively; the dropping time of the water-soluble silicone polymer resin and the thirdly added deionized water is controlled at 45-60min respectively.

8. The method for preparing high-purity, high-modulus potassium silicate solution according to claim 1, characterized in that: In step S7, the mass proportion of the concentrated potassium silicate solution, the silica sol, the deionized water, the methyltrimethoxysilane and the water-soluble silicone polymer resin in the total solution is 30-80%, 5.0-40%, 5.0-30%, 3.0-6.0%, 0.5-1.5% respectively.

9. A high purity high modulus potassium silicate solution characterized by, The high-purity high-modulus potassium silicate solution is prepared by the preparation method of any one of claims 1-8.