CN110194458B - Silica sol and preparation method thereof - Google Patents
Silica sol and preparation method thereof Download PDFInfo
- Publication number
- CN110194458B CN110194458B CN201810156251.7A CN201810156251A CN110194458B CN 110194458 B CN110194458 B CN 110194458B CN 201810156251 A CN201810156251 A CN 201810156251A CN 110194458 B CN110194458 B CN 110194458B
- Authority
- CN
- China
- Prior art keywords
- silica sol
- solution
- silicic acid
- concentration
- reaction
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B33/00—Silicon; Compounds thereof
- C01B33/113—Silicon oxides; Hydrates thereof
- C01B33/12—Silica; Hydrates thereof, e.g. lepidoic silicic acid
- C01B33/14—Colloidal silica, e.g. dispersions, gels, sols
- C01B33/141—Preparation of hydrosols or aqueous dispersions
- C01B33/1412—Preparation of hydrosols or aqueous dispersions by oxidation of silicon in basic medium
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2004/00—Particle morphology
- C01P2004/01—Particle morphology depicted by an image
- C01P2004/04—Particle morphology depicted by an image obtained by TEM, STEM, STM or AFM
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Dispersion Chemistry (AREA)
- Inorganic Chemistry (AREA)
- Silicon Compounds (AREA)
Abstract
The invention provides a silica sol and a preparation method thereof, which adopts an ammonia catalysis silicic acid growth method for preparation, wherein in the process of adding an active silicic acid solution into a boiling seed crystal solution to grow the silica sol under a constant liquid level, when the concentration of silicon dioxide reaches a certain concentration, the boiling reaction solution is cooled and reacts for a certain time. The invention determines the cooling time by setting the reaction heat preservation step, so that the reaction conversion rate of the active silicic acid is improved, the active silicon hydroxyl of the particles is reduced, and the stability in high concentration is obviously improved.
Description
Technical Field
The invention relates to a silica sol and a preparation method thereof, belonging to the technical field of functional inorganic nano materials.
Background
The silica sol, also called silicic acid sol or silicon dioxide hydrosol, has the diameter of colloidal particles of about 20-100nm, is an inorganic silicon nano material which is environment-friendly, nontoxic and widely used, and has application in the industrial fields of chemical industry, precision casting, spinning, papermaking, coating, microelectronics and the like. The preparation method of the silica sol mainly comprises a water glass method and a silicon powder method according to the source of raw material silicon dioxide, wherein the water glass method is a common industrial preparation method due to low raw material price and simple preparation method. The acidic silica sol is at a pH of 3-4 and gels gradually during standing, with higher concentrations giving shorter gel times. The concentration of the industrially used acidic silica sol is generally not more than 30%, and the gel time is about 2 to 5 days. In order to avoid sodium and potassium ions from polluting silica sol, for the preparation of high-purity acidic silica sol with strictly limited sodium and potassium ions, an ammonia-catalyzed silicic acid growth method is generally adopted to generate spherical silica sol in a boiling aqueous solution with alkaline pH of 9-11, but the stability of the silica sol prepared by the method is not as good as that of silica sol prepared by sodium and potassium catalysis, the stability cannot be obviously improved even if the reaction time is prolonged or the reaction temperature is increased, and the viscosity of the silica sol is larger than that of silica sol prepared by sodium and potassium catalysis.
The high-concentration high-purity acidic silica sol has obvious effects of improving performance and reducing cost in the technical fields of high-density batteries, inorganic fibers, aerogels and the like, but the application is limited due to short stabilization time. There are generally several methods to improve the stability of silica sols: 1. increasing the ionic charge in the electric double layer and increasing the electrostatic repulsive force between particles; 2. adjusting the pH value to be less than 2 or more than 10 in a stable interval; 3. the relative number and activity of active silicon hydroxyl groups are reduced. Because the content of impurity metal ions cannot be increased and the method needs to be used in a weakly acidic environment, the former two methods are inconvenient to adopt and only the method of reducing the quantity and activity of silicon hydroxyl groups is used, so that the conversion rate of silicic acid is effectively improved and the density of the silicon hydroxyl groups on the surface of the silica sol is reduced under the condition of ammonia catalysis, the probability of mutual reaction of silica sol particles is reduced, and the stability of the high-concentration silica sol can be obviously improved.
There are many studies on the factors affecting the preparation of acidic silica sol and its stability, such as increasing the reaction speed and increasing the particle size of silica sol particles by high temperature and pressure conditions, and decreasing the number of silica hydroxyl groups by decreasing the total surface area of the particles, e.g., the gel time can be as long as 16 days at 25% concentration (silica particle size affects the stability of acidic silica sol, proceedings of university of eastern science and technology, 2003, 12, vol.29, No.6), but increasing the particle size requires many times of repeated growth reactions; the reaction of peraluminate and silica sol surface silica hydroxyl forms aluminosilicate negative ions, active silica hydroxyl is consumed, and high-concentration stable silica sol is prepared, but Al ions are introduced to become new impurities (the research status and progress of modified silica sol, China adhesive, 2016, 11 th volume, 25 th volume, 11 th volume); CN 102432027A uses organic acid to replace the surface hydroxyl of the silica sol, which also realizes the improvement of stability, but introduces organic groups, which affects the purity of the silica sol.
Disclosure of Invention
The invention aims to overcome the defects of the prior art and provide the silica sol which does not influence the purity, has simple process and good stability at high concentration and the preparation method thereof.
The technical solution of the invention is as follows: a silica sol is prepared by an ammonia-catalyzed silicic acid growth method, in the process of adding an active silicic acid solution into a boiling seed crystal solution to grow the silica sol under a constant liquid level, when the concentration of silicon dioxide (silicon dioxide accounts for 5-10% of the mass of a reaction solution), the addition of the active silicic acid solution is stopped, the boiling reaction solution is cooled to 60-80 ℃, and the heat preservation reaction is carried out for not less than 1 hour.
The heat preservation reaction time is preferably 1-12 hours, and in the preferred range, under the condition that other conditions are not changed, the longer the heat preservation reaction time is, the longer the gel time of the final silica sol can be correspondingly prolonged; beyond the preferable range, if the time is too short, the effect on the prolongation of the gel time (improvement of stability) is not significant, and if the time is too long, the prolongation of the gel time is not significantly changed.
The reaction temperature of the reaction solution is preferably 60-80 ℃, and in the preferred range, under the condition that other conditions are not changed, the higher the reaction temperature is, the longer the gel time of the final silica sol can be correspondingly prolonged; beyond the preferred range, if the reaction temperature is too high or too low, the effect on the extension of the gel time (stability improvement) is not significant.
When the reaction liquid is cooled, the concentration of silicon dioxide in the reaction liquid (silicon dioxide accounts for the mass percent of the reaction liquid) is preferably 5-10%, and in the preferred range, under the condition that other conditions are not changed, the higher the concentration of the silicon dioxide is, the shorter the gel time of the final silica sol is; beyond the preferred range, the concentration of silica is too high or too low and the effect on the extension of the gel time (stability improvement) is not significant.
The ammonia-catalyzed silicic acid growth method comprises the steps of preparing an active silicic acid solution, preparing a seed crystal solution, adding active silicic acid into the boiling seed crystal solution under a constant liquid level to grow silica sol and the like, and is a known technology in the field. In the step of adding active silicic acid into a boiling seed crystal solution to grow the silica sol under a constant liquid level, a proper cooling time is selected, the reaction liquid is cooled to 60-80 ℃ from a boiling state, the reaction is carried out at a lower temperature, ammonia volatilization is greatly reduced relative to the boiling of the solution, the pH value of the solution is kept stable, the residual silicic acid is gradually reacted and reduced at the temperature, adjacent silicon hydroxyl groups on the surfaces of formed silica sol particles gradually react to lose activity, the probability of mutual reaction of the silica sol particles is reduced, and the stability of the silica sol against gelation is improved.
The silica sol obtained by the method is subjected to acid-base neutralization reaction and concentration to obtain high-concentration silica sol with the pH value of 3-4, the silica concentration of 40-55% and the sodium ion content of less than 50ppm, and the gel time of the high-concentration silica sol is more than 40 days.
A preparation method of silica sol is realized by the following steps:
firstly, preparing an active silicic acid solution;
the step is well known in the art, and a person skilled in the art can select different preparation modes according to needs, and can also adopt the following modes:
and (3) diluting the water glass solution, and then passing the diluted water glass solution through a cation exchange resin column and an anion exchange resin column to remove metal ions and hetero ions to obtain an active silicic acid solution with the concentration of 3-5%.
Secondly, preparing a seed crystal solution;
the step is well known in the art, and a person skilled in the art can select different preparation modes according to needs, and can also adopt the following modes:
a2.1, adjusting the active silicic acid solution prepared in the first step to a silicic acid aqueous solution with the pH value of 9-11 and the concentration of 1-2% by using ammonia water;
a2.2, heating the silicic acid aqueous solution obtained in the step A2.1 to boiling, cooling to room temperature, and aging for 8-24 hours to form a seed crystal solution;
the step is a known technology in the field, the aging time has an influence on the gel time of the final silica sol, and under the condition of no change of other conditions, the longer the aging time is, the longer the gel time of the final silica sol is within a preferred range; beyond the preferred range, the aging time is too long or too short, and the effect on the extension of the gel time (stability improvement) is not significant.
Thirdly, adding the active silicic acid solution obtained in the first step into a boiling seed crystal solution under a constant liquid level, and stopping adding the active silicic acid solution when the concentration of silicon dioxide (silicon dioxide accounts for 5-10% of the mass of the reaction solution) in the reaction solution reaches;
step four, cooling the temperature of the reaction solution obtained in the step three to 60-80 ℃, carrying out heat preservation reaction for not less than 1 hour, and keeping the pH value at 9-11 by using ammonia water to obtain alkaline silica sol;
fifthly, converting the alkaline silica sol obtained in the fourth step into acidity;
in engineering, a cation exchange column is generally used for removing ammonia to convert the silica sol into acidity, and other modes without introducing impurities can be adopted for conversion, so long as the acidic silica sol with the pH of 3-4 can be obtained.
And sixthly, concentrating the acidic silica sol obtained in the fifth step to the required concentration.
The concentration method can adopt ultrafiltration membrane or reduced pressure distillation concentration, and also adopts other conventional concentration modes.
The high-concentration silica sol prepared by the method has the advantages that the concentration of silica reaches 40-55%, and the content of sodium ions is lower than 50ppm, and the gel time is more than 40 days.
Compared with the prior art, the invention has the beneficial effects that:
(1) the reaction heat preservation step is arranged, the cooling time is determined, the reaction conversion rate of the active silicic acid is improved, the active silicon hydroxyl of the particles is reduced, and the stability in high concentration is obviously improved;
(2) compared with the common process, the method does not add special equipment, has mild reaction conditions, and has the characteristics of simple operation method, suitability for industrial production and obvious effect of improving the product performance;
(3) the high-concentration silica sol prepared by the method has the silica concentration of 40-55% and the gel time of more than 40 days.
Drawings
FIG. 1 is a flow chart of the present invention;
FIG. 2 is a transmission electron micrograph of a high concentration silica sol prepared by example 1 of the present invention;
FIG. 3 is a transmission electron micrograph of a silica sol prepared by comparative example 1 of the prior art.
Detailed Description
The present invention will be described in detail with reference to the following examples and accompanying drawings.
Example 1
The preparation process is shown in figure 1 and is realized by the following steps:
1. preparation of active silicic acid solution
Preparing active silicic acid solution with concentration of 4%, viscosity of 3mPa.S, removing metal and other hetero-ions by cation and anion exchange columns, and pH value of 3.
2. Preparation of seed solution
And (3) diluting the active silicic acid solution obtained in the step (1) to 1%, adjusting the pH value of the 1% silicic acid aqueous solution to 9-11 with ammonia water, heating to boil, and aging at room temperature for 8h to obtain a silica sol crystal seed solution with reaction activity.
3. And (2) taking 1000mL of seed crystal solution, adjusting the pH value of the aqueous solution to be 9-11 in the reaction period by using ammonia water, heating the solution to boiling, gradually adding the active silicic acid solution obtained in the step (1) into the boiling seed crystal solution at a certain speed, keeping the volume of the solution constant, and stopping adding the active silicic acid solution when the concentration of silicon dioxide in the reaction solution reaches 10%.
4. And (3) naturally cooling the reaction liquid in the step (3) to 80 ℃, preserving the heat for 2 hours at the temperature, keeping stirring and adjusting the pH value to be constant by using ammonia water, and then naturally cooling to room temperature.
5. The silica sol solution was passed through a cation exchange resin column to give an acidic silica sol having a concentration of about 10% and a pH of 4.
6. Concentrating with ultrafiltration membrane to 50%.
The high-concentration silica sol prepared in this example (as shown in FIG. 2) had a viscosity of 8.5mPa.s, a sodium ion content of 44ppm, and a gel time of 45 days under an ambient temperature environment.
Comparative example 1
Preparing an active silicic acid solution with the concentration of 4% and the viscosity of 3mPa.S, removing metal and other foreign ions by a cation and anion exchange column, and the pH value of 3, adjusting the pH value of a 1% silicic acid aqueous solution to 9-11 by ammonia water, heating to boiling, and aging at room temperature for 8h to obtain a reactive silica sol seed crystal particle solution.
Taking 1000mL of seed crystal solution, adjusting the pH value of the aqueous solution to be 9-11 in a reaction period by using ammonia water, heating the solution to boiling, simultaneously gradually adding the active silicic acid solution into the boiling seed crystal solution at a certain speed, keeping the volume of the solution constant, stopping adding silicic acid when the concentration of silicon dioxide in the reaction solution reaches 10%, keeping the boiling for 2 hours, keeping the volume and the pH value of the solution constant by adding ammonia water and pure water, and naturally cooling to obtain a silica sol solution.
The silica sol solution was passed through a cation exchange resin column to give an acidic silica sol having a concentration of about 10% and a pH of 4 (shown in FIG. 3). Then concentrating by an ultrafiltration membrane until the concentration is 50%, the viscosity is 70.0mPa.s, the Na ion content is 43ppm, and the gel time is 7 days under the normal temperature environment.
As can be seen from FIGS. 2 and 3, the silica sols obtained in example 1, which have a small difference in particle size from those obtained in comparative example 1, show a significant difference in the degree of agglomeration, indicating the strength of the gel tendency, and the viscosity of the silica sols according to the invention is significantly reduced, indicating the effectiveness of the invention.
Example 2
Preparing an active silicic acid solution with the concentration of 3 percent and the viscosity of 2mPa.S, removing metal and other foreign ions by a cation-anion exchange column, adjusting the pH value of a 1 percent silicic acid aqueous solution to 9-11 by ammonia water, heating to boil, and aging for 24h to obtain a silica sol seed crystal solution with reaction activity.
Taking 2000mL of seed crystal solution, adjusting the pH value of the aqueous solution to be 9-11 in a reaction period by using ammonia water, heating the solution to boiling, simultaneously gradually adding the active silicic acid solution into the boiling seed crystal solution at a certain speed, keeping the volume of the solution constant, and stopping adding silicic acid when the concentration of silicon dioxide in the reaction solution reaches 5% to obtain a silica sol solution. Naturally cooling to 80 deg.C, and keeping the temperature at the temperature for 4 hr while maintaining stirring and pH range.
The silica sol solution was passed through a cation exchange resin column to give an acidic silica sol having a concentration of about 5% and a pH of 4. Then concentrating by an ultrafiltration membrane until the concentration is 45%, the viscosity is 5.5mPa.s, the Na ion content is 42ppm, and the gel time is 50 days under the normal temperature environment.
Example 3
Preparing an active silicic acid solution with the concentration of 5 percent and the viscosity of 3.5mPa.S, removing metal and other foreign ions by a cation-anion exchange column, and the pH value of 4, diluting silicic acid to 1 percent by pure water, adjusting the pH value of the solution to 9-10 by ammonia water, heating to boil, and aging for 18h to obtain the silica sol seed crystal solution with reaction activity.
Taking 5000mL of seed crystal solution, adjusting the pH value of the aqueous solution to be 9-11 in a reaction period by using ammonia water, heating the solution to boiling, simultaneously gradually adding the active silicic acid solution into the boiling seed crystal solution at a certain speed, keeping the volume of the solution constant, and stopping adding silicic acid when the concentration of silicon dioxide in the reaction solution reaches 8% to obtain a silica sol solution. Naturally cooling to 60 deg.C, and keeping the temperature at the temperature for 8 hr while maintaining stirring and pH range.
The silica sol solution was passed through a cation exchange resin column to give an acidic silica sol having a concentration of about 8% and a pH of 4. Then concentrating by an ultrafiltration membrane until the concentration is 55%, the viscosity is 9.2mPa.s, the Na ion content is 40ppm, and the gel time is 48 days under the normal temperature environment.
The invention has not been described in detail and is in part known to those of skill in the art.
Claims (8)
1. The silica sol is prepared by an ammonia-catalyzed silicic acid growth method, and is characterized in that: in the process of adding the active silicic acid solution into the boiling seed crystal solution to grow the silica sol under a constant liquid level, when the concentration of silicon dioxide in the reaction solution reaches 5-10%, stopping adding the active silicic acid solution, reducing the boiling reaction solution to 60-80 ℃, and carrying out heat preservation reaction for not less than 1 hour.
2. A silica sol according to claim 1, characterized in that: the heat preservation reaction time is 1-12 hours.
3. A silica sol preparation method is characterized by comprising the following steps:
firstly, preparing an active silicic acid solution;
secondly, preparing a seed crystal solution;
thirdly, adding the active silicic acid solution obtained in the first step into a boiling seed crystal solution under a constant liquid level, and stopping adding the active silicic acid solution when the concentration of silicon dioxide in a reaction solution reaches 5-10%;
step four, cooling the temperature of the reaction solution obtained in the step three to 60-80 ℃, carrying out heat preservation reaction for not less than 1 hour, and keeping the pH value at 9-11 by using ammonia water to obtain alkaline silica sol;
fifthly, converting the alkaline silica sol obtained in the fourth step into acidity;
and sixthly, concentrating the acidic silica sol obtained in the fifth step to the required concentration.
4. A silica sol production method according to claim 3, characterized in that: in the first step, the water glass solution is diluted and then passes through cation and anion exchange resin columns to remove metal ions and foreign ions, so that an active silicic acid solution with the concentration of 3-5% is obtained.
5. A silica sol production method according to claim 3, characterized in that: the second step of preparing the seed solution is accomplished by,
a2.1, adjusting the active silicic acid solution prepared in the first step to a silicic acid aqueous solution with the pH value of 9-11 and the concentration of 1-2% by using ammonia water;
and A2.2, heating the silicic acid aqueous solution obtained in the step A2.1 to boiling, cooling to room temperature, and aging for 8-24 hours to form a seed crystal solution.
6. A silica sol production method according to claim 3, characterized in that: and the fourth step is carried out for 1-12 hours.
7. A silica sol production method according to claim 3, characterized in that: and in the fifth step, ammonia is removed by using a cation exchange column, so that the silica sol is converted into acidity, and the acidic silica sol with the pH of 3-4 is obtained.
8. A silica sol production method according to claim 3, characterized in that: and sixthly, adopting an ultrafiltration membrane or reduced pressure distillation and concentration to obtain silica sol with the silica concentration of 40-55%.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810156251.7A CN110194458B (en) | 2018-02-24 | 2018-02-24 | Silica sol and preparation method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810156251.7A CN110194458B (en) | 2018-02-24 | 2018-02-24 | Silica sol and preparation method thereof |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN110194458A CN110194458A (en) | 2019-09-03 |
| CN110194458B true CN110194458B (en) | 2021-03-23 |
Family
ID=67743944
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201810156251.7A Active CN110194458B (en) | 2018-02-24 | 2018-02-24 | Silica sol and preparation method thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN110194458B (en) |
Family Cites Families (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| NO300125B1 (en) * | 1988-03-16 | 1997-04-14 | Nissan Chemical Ind Ltd | Stable liquid silica sol, as well as process for its preparation |
| AU2715597A (en) * | 1996-05-06 | 1997-11-26 | Contact Energy Limited | Manufacture and recovery of monodisperse silica sols from a geothermal brine |
| TW530029B (en) * | 1999-11-17 | 2003-05-01 | Akzo Nobel Nv | A method for manufacturing of silica sols |
| JPWO2007007751A1 (en) * | 2005-07-12 | 2009-01-29 | 日産化学工業株式会社 | Surface-treated silica sol, method for producing the same, and inkjet recording medium |
| JP5127452B2 (en) * | 2005-08-10 | 2013-01-23 | 日揮触媒化成株式会社 | Method for producing deformed silica sol |
| CN101070161B (en) * | 2007-03-27 | 2011-12-14 | 鲁东大学 | Method for preparing high-activity silicon collidal sol formed from superfine silicon dioxide particles |
| CN101402829A (en) * | 2008-11-11 | 2009-04-08 | 天津西立卡晶体抛光材料有限公司 | White potato shaped silicon dioxide colloidal sol and method of producing the same |
| CN102390837A (en) * | 2011-08-03 | 2012-03-28 | 南通海迅天恒纳米科技有限公司 | Preparation method of nonspherical nanometer-scale silica sol |
| CN103896290B (en) * | 2012-12-28 | 2016-01-20 | 上海新安纳电子科技有限公司 | A kind of stable modified silicasol and preparation method thereof |
| KR102242683B1 (en) * | 2013-04-17 | 2021-04-23 | 실본드 코포레이션 | Colloidal sol and method of making same |
| CN105883824B (en) * | 2016-04-12 | 2018-06-29 | 广东惠和硅制品有限公司 | A kind of preparation method of big grain size Ludox |
| CN106006651B (en) * | 2016-05-17 | 2018-09-07 | 华微科技（苏州）有限公司 | Acidic silicasol and preparation method thereof |
| CN106044786B (en) * | 2016-06-01 | 2019-05-07 | 上海新安纳电子科技有限公司 | Big partial size silica solution of polydispersion and preparation method thereof |
-
2018
- 2018-02-24 CN CN201810156251.7A patent/CN110194458B/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| CN110194458A (en) | 2019-09-03 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| TWI520904B (en) | Process for preparing aqueous colloidal silica sols of high purity from alkali metal silicate solutions | |
| US5100581A (en) | Method of preparing high-purity aqueous silica sol | |
| CN111470510B (en) | Silica sol with controllable particle form and preparation method thereof | |
| JP3463328B2 (en) | Method for producing acidic silica sol | |
| CN111484024B (en) | Preparation method of silicon dioxide with low oil absorption value and high specific surface area | |
| CN111732107B (en) | Method for preparing high-concentration silica sol with ultra-large particle size by using water glass | |
| CN102040868A (en) | Method for preparation and surface modification of alkaline silicon sol | |
| CN103588210A (en) | Preparation method of nano silicon dioxide | |
| CN110482559B (en) | Aluminum modified acidic silica sol and preparation method and application thereof | |
| CN103848427B (en) | A kind of high dispersive precipitated silica and preparation method thereof | |
| CN110194458B (en) | Silica sol and preparation method thereof | |
| CN104445222B (en) | A kind of big particle diameter and the preparation method of the acidic silicasol that is evenly distributed | |
| CN111302347B (en) | Preparation method of high-purity large-particle-size silica sol | |
| JP2020040868A (en) | Method for producing synthesized quartz powder | |
| CN104961134A (en) | Silica sol and preparation method thereof | |
| CN104860322B (en) | A kind of preparation method of low sodium ions content high-purity silicasol | |
| CN114408934A (en) | Preparation method of nano silicon dioxide | |
| CN114160093A (en) | Iron-amino functionalized mesoporous silica and preparation method and application thereof | |
| CN104418335A (en) | Silica hydrosol and preparation method and application thereof | |
| CN114249330A (en) | Method for preparing large-particle-size narrow-distribution silica sol | |
| JP5405023B2 (en) | Colloidal silica composed of silica particles with imidazole immobilized | |
| US3711419A (en) | Process for preparing silica aquasols | |
| CN111099599A (en) | Lithium silicate solution and preparation method thereof | |
| CN114314598B (en) | Silica sol and preparation method thereof | |
| US2940939A (en) | Process of preparing silica sols |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |