CN112429738A - Silicon dioxide etching process method - Google Patents
Silicon dioxide etching process method Download PDFInfo
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- CN112429738A CN112429738A CN202011202119.9A CN202011202119A CN112429738A CN 112429738 A CN112429738 A CN 112429738A CN 202011202119 A CN202011202119 A CN 202011202119A CN 112429738 A CN112429738 A CN 112429738A
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- 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
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- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25F—PROCESSES FOR THE ELECTROLYTIC REMOVAL OF MATERIALS FROM OBJECTS; APPARATUS THEREFOR
- C25F3/00—Electrolytic etching or polishing
- C25F3/02—Etching
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- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
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Abstract
The invention provides a silicon dioxide etching process method, which specifically comprises the following steps: (1) adding silicon dioxide and ionic liquid into an electrolytic cell; (2) introducing current to carry out electrolysis operation; (3) and after the electrolytic reaction is finished, washing and drying the generated porous silicon dioxide product to obtain a final product. According to the invention, the silicon dioxide product with the hollowed-out structure on the surface is obtained by electrochemically etching the silicon dioxide in the ionic liquid medium, and the etched product has the advantages of large aperture and strong loading capacity, and has great potential application value in the aspects of medicine carriers and biological health care.
Description
Technical Field
The invention relates to the field of silicon dioxide etching process methods, in particular to a method for preparing porous silicon dioxide in ionic liquid by adopting an electrochemical etching method.
Background
Silica is commonly called white carbon black, and is a compound with wide sources and no toxicity and harm. The silicon dioxide is hard in texture and low in price and is widely applied to national production and life. The high specific area silicon dioxide has ultrahigh oil absorption value and has important function in the fields of paint, wires and cables, adhesion, carriers for feed and the like. In the field of tires, the wear resistance and strength of the tires can be greatly improved due to the excellent reinforcing property and dispersibility; in the field of carriers, the carrier is widely applied to feed vitamin carriers or biological medicine carriers due to the characteristics of no toxicity, no harm and high adsorbability.
At present, the domestic silicon dioxide production methods mainly comprise two methods: one is the preparation of silicon dioxide by a gas phase method, the process conditions are harsh, the technical threshold is high, the production cost is high, although nano-scale silicon dioxide can be produced, due to the process technical reasons, only nano-scale spherical products can be produced, and silicon dioxide products with porous structures cannot be produced, so the application field of carriers is greatly limited; the other is silicon dioxide prepared by a precipitation method, the process is simple, the cost is low, silicon dioxide products with different specific surface areas can be prepared by controlling different conditions in the production process, but the silicon dioxide products with porous hollow structures cannot be produced.
With the coming of the times of the health of the whole people, the development of biological medicines is rapidly strengthened. Some pharmaceutical ingredients must be loaded onto a carrier in order for efficacy to occur more efficiently in the human or animal body. The silica is widely applied due to the characteristics of no toxicity, no harm and low price, for example, the patent CN201710562955.X discloses sorafenib drug-loaded mesoporous silica; patent CN201911016670.1 discloses a silica as a carrier for drugs.
The preparation method of the silicon dioxide for the mesoporous carrier mainly comprises the following steps: 1) the preparation method is characterized in that silicate is used as a raw material, a surfactant is added, the pH value is adjusted to react, and finally the high-temperature heating is carried out to prepare the silicon-based catalyst. For example, patent CN202010266374.3 adopts such a method to prepare, but the method is expensive in raw materials and can only prepare mesoporous silica; 2) sodium silicate is used as a starting material for preparation. The main process of the method is to add a surfactant into a prepared sodium silicate solution, to cure a seed crystal solution by adjusting the pH value, and to obtain a high-bulk-density silicon dioxide product after pressure filtration and drying. For example, patent CN201811067436.7 is to prepare a mesoporous silica product by the method. Although these methods can prepare silica having a certain adsorption effect, the loading capacity and pore size are limited, and it is difficult to satisfy the requirements of large-capacity adsorption and high loading, especially, the reaction process requires strict control of process conditions and process flows, and thus the competitiveness is limited.
In view of the above, the present invention is particularly proposed.
The invention content is as follows:
in order to solve the problem that large mesoporous and high-load silica is difficult to prepare, the invention provides a silica etching process technology, which etches the silica by carrying out electrochemical reaction in ionic liquid, thereby preparing a silica product with large aperture and high load effect.
The problem solved by the invention is realized by the following steps:
the etching process method takes ionic liquid as a medium to carry out electrolytic etching on silicon dioxide to prepare porous silicon dioxide.
Specifically, the etching process method specifically comprises the following steps:
(1) adding silicon dioxide and ionic liquid into an electrolytic cell;
(2) introducing current to carry out electrolysis operation;
(3) and after the electrolytic reaction is finished, washing and drying the generated porous silicon dioxide product to obtain a final product. The invention takes the ionic liquid as the medium to carry out electrolytic etching on the silicon dioxide to prepare the large-aperture silicon dioxide, and the large-aperture silicon dioxide has large specific surface area, strong loading capacity and wide application prospect.
Further, the adding amount of the silicon dioxide is 10-40% of the mass of the ionic liquid.
Further, the ionic liquid is a tetrafluoroborate aqueous solution or a hexafluorophosphate aqueous solution.
According to some embodiments of the present invention, preferably, the ionic liquid is an aqueous solution of 1-butyl-3-methylimidazolium tetrafluoroborate or an aqueous solution of 1-butyl-3-methylimidazolium hexafluorophosphate. .
The invention discovers that the large-aperture silicon dioxide is prepared by etching silicon dioxide through an electrolytic process by using a fluorine-containing salt solution as an ionic liquid.
Preferably, the concentration mass fraction of the ionic liquid is 1-2%.
Preferably, the silica is granular with the mesh number of 150-300.
Further, in the step (2), the current density is 8-24mA/cm2The electrolysis time is 4-6 h.
Further, in the step (3), the washing solution is deionized water, the drying temperature is 100-120 ℃, and the drying time is 2-3 h.
Further, the invention provides a preparation method of an antibacterial filter, which comprises the porous silicon dioxide, and the preparation method comprises the following steps:
(1) firstly, uniformly mixing a glacial acetic acid aqueous solution and chitosan to prepare a chitosan-acetic acid solution, mixing and stirring the chitosan-acetic acid solution and 3-glycidyl ether trimethoxy silane overnight, adding porous silicon dioxide powder into the overnight solution, stirring and centrifuging, and then washing with ultrapure water to obtain a chitosan-porous silicon dioxide composite material;
(2) adding water into the chitosan-porous silicon dioxide composite material prepared in the step (1) to prepare a solution with the concentration of 100g/L, impregnating and compounding the solution with non-woven fabrics, pre-drying and baking the composite sample, and curing by ultraviolet light to prepare the antibacterial filter sheet.
Compared with the prior art, the invention has the advantages that:
(1) the invention directly carries out electrochemical etching on the silicon dioxide product without strict operating conditions and process control.
(2) The invention adopts the electrochemical etching production process, is green and environment-friendly, has simple process flow and is easy to realize industrial production.
(3) The inventionAnd electrochemically etching silicon dioxide in an ionic liquid medium to obtain a silicon dioxide product with a hollow structure on the surface. The aperture of the etched product reaches 80-100nm, and the specific surface area reaches 800-2The prepared silicon dioxide has the advantages of large aperture and strong loading capacity. Has great potential application value in the aspects of medical carriers and biological health care.
Drawings
FIG. 1 is an electron micrograph of silicon dioxide after etching.
Detailed Description
The present invention is described in detail below with reference to examples, but the present invention is not limited thereto. Any modification or improvement that comes within the principles of this invention is considered to be within the scope of this invention.
Example 1
100g of 150-mesh silicon dioxide and 900g of 1 mass percent 1-butyl-3-methylimidazolium tetrafluoroborate aqueous solution are added into an electrolytic bath for electrolytic reaction. The current intensity is 8mA/cm2And electrifying for reaction for 6 h. And washing the product by using deionized water after the reaction is finished, drying the product at the temperature of between 100 and 120 ℃ for 3 hours after the product is washed, and finally preparing the etched hollow surface porous silicon dioxide product.
Example 2
100g of 300-mesh silicon dioxide and 800g of 2 mass percent aqueous solution of 1-butyl-3-methylimidazolium hexafluorophosphate are added into an electrolytic bath for electrolytic reaction. The current intensity is 24mA/cm2And electrifying for reaction for 6 h. And washing the product by using deionized water after the reaction is finished, drying at 120 ℃ for 3 hours after washing, and finally preparing the etched hollow surface porous silicon dioxide product.
Example 3
100g of 300-mesh silicon dioxide and 900g of 2 mass percent aqueous solution of 1-butyl-3-methylimidazolium hexafluorophosphate are added into an electrolytic bath for electrolytic reaction. The current intensity is 18mA/cm2And electrifying for reaction for 6 h. Washing the product with deionized water after the reaction is finished, drying the product at the temperature of 120 ℃ for 3 hours after washing, and finally preparing the productAnd (5) etching the hollow surface porous silicon dioxide product.
Example 4
100g of 200-mesh silicon dioxide and 400g of 2 mass percent 1-butyl-3-methylimidazolium tetrafluoroborate aqueous solution are added into an electrolytic bath for electrolytic reaction. The current intensity is 16mA/cm2And electrifying for reaction for 3 h. And washing the product by using deionized water after the reaction is finished, drying the product at the temperature of between 100 and 120 ℃ for 2 hours after the product is washed, and finally preparing the etched hollow surface porous silicon dioxide product.
Example 5
100g of 250-mesh silicon dioxide and 300g of 2 mass percent 1-butyl-3-methylimidazolium hexafluorophosphate aqueous solution are added into an electrolytic bath for electrolytic reaction. The current intensity is 12mA/cm2And electrifying for reaction for 5 h. And washing the product by using deionized water after the reaction is finished, drying the product at the temperature of between 100 and 120 ℃ for 2 hours after the product is washed, and finally preparing the etched hollow surface porous silicon dioxide product.
Example 6
Firstly, uniformly mixing a glacial acetic acid aqueous solution with the mass fraction of 4% and chitosan to prepare a chitosan-acetic acid solution with the mass fraction of 1%. And (3) mixing 50ml of chitosan-acetic acid solution with 3ml of 3-glycidyl ether trimethoxy silane, stirring overnight, adding the porous silicon dioxide powder prepared in the example 3 into the liquid overnight, stirring, centrifuging, and washing with ultrapure water to obtain the chitosan-porous silicon dioxide composite material. Wherein the mass ratio of the chitosan to the porous silicon dioxide is as follows: 5:0.05.
Dissolving acrylic acid oligomer in acetic acid solution to prepare solution with the mass fraction of 8-30% to obtain spray solution 1;
dissolving a chitosan-porous silicon dioxide composite material in an acetic acid solution to prepare a chitosan-porous silicon dioxide composite solution with the concentration of 100g/L, adding a certain amount of ultraviolet crosslinking monomer, and uniformly stirring to obtain a spray solution 2; the ultraviolet crosslinking monomer is as follows: dicyclopentadienyl acrylate. The acrylic acid oligomer, the chitosan-porous silicon dioxide and the ultraviolet crosslinking monomer are prepared from the following components in parts by mass: 0.2:1:0.4.
Firstly, opening a spray head 2 of a spray solution to carry out electrostatic spraying on the non-woven fabric for 1-2min, wherein the flow rate is as follows: 600ul/min, then opening a spray head of the spraying solution 1 to perform electrostatic spraying on the non-woven fabric at the flow rate of 800ul/min, spraying the spraying solution 1 and the spraying solution 2 at the same time, performing pre-drying at 50 ℃ for 6min and baking at 120 ℃ for 6min after spraying, and then performing ultraviolet crosslinking curing to obtain the antibacterial filter sheet.
The antibacterial rate of the filter plate can reach more than 93%, and the haze protection rate can reach more than 90%.
Experimental example 1 screening of different Ionic liquids
The preparation method adopts the preparation process described in example 3, except that the ionic liquid is different, and the porous silicon dioxide is prepared, and the specific research results are shown in table 1.
TABLE 1
The invention takes the ionic liquid as a medium and further screens the ionic liquid, wherein the invention discovers that the etching effect on silicon dioxide can be further improved in the electrolytic process by adopting a tetrafluoroborate aqueous solution or a hexafluorophosphate aqueous solution as the ionic liquid, and preferably, the tetrafluoroborate aqueous solution or the hexafluorophosphate aqueous solution containing imidazole, and the etched silicon dioxide has large aperture, uniform aperture particle size distribution and better loading capacity.
Experimental example 2 screening of different electrolytic conditions
The preparation method adopts the preparation process described in the embodiment 3, and is different in current intensity, so that the porous silicon dioxide is prepared, and the specific research result is shown in table 2.
TABLE 2
The invention further researches the electrolysis conditions, particularly further screens the current intensity, and finds that the size of the current intensity can also influence the etching effect on the silicon dioxide, if the current intensity is too small, the aperture of the prepared silicon dioxide is smaller, and if the current intensity is too large, although the aperture of the silicon dioxide is larger, the aperture diameter is not uniform, the loading capacity of the product is influenced, and the product yield is low.
Although the present invention has been described in detail with reference to the foregoing embodiments, it will be apparent to those skilled in the art that changes may be made in the embodiments and/or equivalents thereof without departing from the spirit and scope of the invention. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (10)
1. A silicon dioxide etching process method is characterized in that: the etching process method takes ionic liquid as a medium to carry out electrolytic etching on silicon dioxide to prepare the porous silicon dioxide.
2. The etching process method according to claim 1, characterized in that: the etching process method specifically comprises the following steps:
(1) adding silicon dioxide and ionic liquid into an electrolytic cell;
(2) introducing current to carry out electrolysis operation;
(3) and after the electrolytic reaction is finished, washing and drying the generated porous silicon dioxide product to obtain a final product.
3. The etching process method according to claim 1 or 2, characterized in that: the adding amount of the silicon dioxide is 10-40% of the mass of the ionic liquid.
4. The etching process method according to claim 1 or 2, characterized in that: the ionic liquid is tetrafluoroborate aqueous solution or hexafluorophosphate aqueous solution.
5. The etching process method according to claim 4, wherein: the ionic liquid is 1-butyl-3-methylimidazole tetrafluoroborate aqueous solution or 1-butyl-3-methylimidazole hexafluorophosphate aqueous solution.
6. The etching process method according to claim 1 or 2, characterized in that: the concentration mass fraction of the ionic liquid is 1-2%.
7. The etching process method according to claim 1 or 2, characterized in that: the silicon dioxide is granular and has the mesh number of 150-300.
8. The etching process method according to claim 1 or 2, characterized in that: in the step (2), the current density is 8-24mA/cm2The electrolysis time is 4-6 h.
9. The etching process method according to claim 1 or 2, characterized in that: in the step (3), the washing solution is deionized water, the drying temperature is 100-120 ℃, and the drying time is 2-3 h.
10. A method for preparing an antibacterial filter comprising the porous silica according to any one of claims 1 to 9, characterized in that: the preparation method comprises the following steps:
(1) firstly, uniformly mixing a glacial acetic acid aqueous solution and chitosan to prepare a chitosan-acetic acid solution, mixing and stirring the chitosan-acetic acid solution and 3-glycidyl ether trimethoxy silane overnight, adding porous silicon dioxide powder into the overnight solution, stirring and centrifuging, and then washing with ultrapure water to obtain a chitosan-porous silicon dioxide composite material;
(2) adding water into the chitosan-porous silicon dioxide composite material prepared in the step (1) to prepare a solution with the concentration of 100g/L, impregnating and compounding the solution with non-woven fabrics, pre-drying and baking the composite sample, and curing by ultraviolet light to prepare the antibacterial filter sheet.
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| CN202011202119.9A CN112429738A (en) | 2020-11-02 | 2020-11-02 | Silicon dioxide etching process method |
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| CN202011202119.9A CN112429738A (en) | 2020-11-02 | 2020-11-02 | Silicon dioxide etching process method |
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101297654A (en) * | 2008-06-27 | 2008-11-05 | 太原理工大学 | Preparation of silver-loaded silica-chitosan compound anti-bacteria agent |
| WO2012055569A1 (en) * | 2010-10-29 | 2012-05-03 | Max-Planck-Gesellschaft zur Förderung der Wissenschaften e.V | Method for modifying the structural properties of silicon by ultrasonication |
| US20150050816A1 (en) * | 2013-08-19 | 2015-02-19 | Korea Atomic Energy Research Institute | Method of electrochemically preparing silicon film |
| WO2017203063A1 (en) * | 2016-05-27 | 2017-11-30 | Universite De Rennes 1 | Preparation of porous silicon (99.99%) by electro-oxydation of metallurgical grade silicon |
| CN108939142A (en) * | 2018-07-05 | 2018-12-07 | 安徽玉然经编科技有限公司 | A kind of dressing of the microballoon containing composite antibacterial |
-
2020
- 2020-11-02 CN CN202011202119.9A patent/CN112429738A/en not_active Withdrawn
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101297654A (en) * | 2008-06-27 | 2008-11-05 | 太原理工大学 | Preparation of silver-loaded silica-chitosan compound anti-bacteria agent |
| WO2012055569A1 (en) * | 2010-10-29 | 2012-05-03 | Max-Planck-Gesellschaft zur Förderung der Wissenschaften e.V | Method for modifying the structural properties of silicon by ultrasonication |
| US20150050816A1 (en) * | 2013-08-19 | 2015-02-19 | Korea Atomic Energy Research Institute | Method of electrochemically preparing silicon film |
| WO2017203063A1 (en) * | 2016-05-27 | 2017-11-30 | Universite De Rennes 1 | Preparation of porous silicon (99.99%) by electro-oxydation of metallurgical grade silicon |
| CN108939142A (en) * | 2018-07-05 | 2018-12-07 | 安徽玉然经编科技有限公司 | A kind of dressing of the microballoon containing composite antibacterial |
Non-Patent Citations (2)
| Title |
|---|
| EVGENIYA A. SAVERINA ET AL.: "Porous Silicon Preparation by Electrochemical Etching in Ionic Liquids", 《ACS SUSTAINABLE CHEM.ENG.》 * |
| JIANMIN WU ET AL.: "Chitosan Hydrogel-Capped Porous SiO2 as a pH Responsive Nano-Valve for Triggered Release of Insulin", 《ADV. FUNCT. MATER.》 * |
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