CN110655101B - Preparation method and application of high-transparency nano zinc oxide - Google Patents
Preparation method and application of high-transparency nano zinc oxide Download PDFInfo
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- CN110655101B CN110655101B CN201911064384.2A CN201911064384A CN110655101B CN 110655101 B CN110655101 B CN 110655101B CN 201911064384 A CN201911064384 A CN 201911064384A CN 110655101 B CN110655101 B CN 110655101B
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- C01—INORGANIC CHEMISTRY
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- C01G9/00—Compounds of zinc
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- C—CHEMISTRY; METALLURGY
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- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2006/00—Physical properties of inorganic compounds
- C01P2006/60—Optical properties, e.g. expressed in CIELAB-values
Abstract
The invention provides a preparation method and application of high-transparency nano zinc oxide. The method comprises the steps of producing zinc chloride liquid with high impurity content by reacting zinc hypoxide with hydrochloric acid, filtering, removing iron, manganese, calcium, magnesium, lead, cadmium and other impurities to obtain refined zinc chloride liquid, adding ammonium bicarbonate into the refined zinc chloride liquid at normal temperature to react to generate basic zinc carbonate and ammonium chloride mother liquor, concentrating the filtered mother liquor ammonium chloride to obtain a byproduct refined ammonium chloride, washing the basic zinc carbonate with pure water at 70 ℃, drying, and calcining at 300 ℃ for one hour to obtain the nano zinc oxide. The content of the transparent zinc oxide in the finished product is more than or equal to 96 percent, the transparency is more than or equal to 90 percent, and the specific surface area is more than or equal to 45 square meters per gram, so that the transparent zinc oxide can be applied to the field of cosmetics.
Description
Technical Field
The invention relates to the field of nano materials, in particular to nano zinc oxide, and particularly relates to a preparation method of high-transparency nano zinc oxide.
Background
The zinc oxide has certain antibacterial and deodorizing functions. The nano zinc oxide added into the sunscreen cosmetic has the following characteristics: (1) the full-wave band protection of UVA and UVB can be provided; (2) excellent dispersibility and transparency; (3) is safe and non-irritant; (4) good light stability.
The nanometer zinc oxide is prepared into nanometer superfine active zinc oxide by wet chemical process (NPP-process), and may be prepared with various zinc-containing material as material, and through acid leaching to leach zinc, repeated purification to eliminate impurity, precipitation to obtain basic zinc carbonate, roasting, etc. For example, the method for preparing nano active zinc oxide from low-grade zinc-containing materials is reported in CN 1193106C. Firstly, acid leaching is carried out on a zinc-containing material, so that zinc enters a solution in the form of zinc sulfate, iron, manganese and arsenic are removed through oxidation, cadmium, copper and other impurities are removed through displacement, the zinc sulfate solution is purified, then alkali liquor and a dispersing agent are added to prepare a precursor basic zinc carbonate, and finally, the precursor basic zinc carbonate is prepared through the procedures of washing, drying and roasting. The method needs to add a dispersant under the heating condition to obtain the basic zinc carbonate.
The main problems existing in the prior art are as follows: (1) a catalyst, a template agent, a dispersing agent or an accelerant is required to be added to increase the reaction rate, control the particle size or prevent agglomeration and the like; (2) the product has low transparency; (3) the purity is lower.
Disclosure of Invention
In view of the above problems, a first object of the present invention is to provide a method for preparing high-transparency nano zinc oxide.
The second purpose of the invention is to provide nano zinc oxide with high transparency.
The third purpose of the invention is to provide the application of the high-transparency nano zinc oxide.
In order to achieve the purpose, the technical scheme provided by the invention is as follows:
s1, preparation of a crude zinc chloride solution: adding zinc hypoxide into hydrochloric acid to react until the pH value is 3-4, adding barium chloride, and filtering;
wherein the content of the hydrochloric acid added into the S1 is 31% and the content of the zinc hypoxide is 55-65% by weight.
S2, preparing a refined zinc chloride solution: removing impurities from the crude zinc chloride solution prepared in the step S1;
wherein the impurity removal comprises removing iron and manganese with an impurity removing agent at 80-90 deg.C, filtering, cooling to 20-30 deg.C, adding mixed solution of sodium ferulate and thiourea, and removing metal ion impurities such as lead, nickel, cadmium, etc. in the solution.
Wherein the ratio of the sodium dimethyl dithiocarbamate to the thiourea in the mixed solution of the sodium dimethyl dithiocarbamate and the thiourea is 2: 1.
Wherein the use amount of the mixed solution of the sodium ferulate and the thiourea is 15 to 20 times of the total weight of the nickel in the crude zinc chloride solution.
S3, preparation of crude basic zinc carbonate: cooling the refined zinc chloride solution prepared in the step S2 to normal temperature, adding an ammonium bicarbonate solution with the weight ratio of 1.1-1.2 times, reacting until the pH value is 6-7, filtering to obtain basic zinc carbonate precipitate, recovering and concentrating the filtrate which is an ammonium chloride mother liquor;
wherein the normal temperature in S3 is 20-30 ℃, and the mass fraction of the ammonium bicarbonate solution is 3%.
S4, preparation of refined basic zinc carbonate: washing the basic zinc carbonate precipitate prepared in the step S3 with pure water until the conductivity is 10-50 us/cm;
wherein the pure water in S4 is pure water at 70 ℃;
s5, preparation of nano zinc oxide: and (4) drying the refined basic zinc carbonate prepared in the step (S4), calcining at the temperature of 250-300 ℃ for 1h, and cooling to obtain the high-transparency nano zinc oxide.
And (3) selecting and performing reaction at normal temperature in S3, wherein the nano zinc oxide obtained by the reaction at normal temperature has smaller particle size and is easier to transmit light compared with the temperature rise reaction. Calcining at the same temperature, reacting at normal temperature with zinc oxide having an electron microscope average particle size of 10-20nm, and reacting at elevated temperature with zinc oxide having an electron microscope average particle size of 40-50 nm. However, since sulfate adsorbed or contained in basic zinc carbonate at ordinary temperature is higher than that in the case of increasing the temperature, it is necessary to wash with pure water at 70 ℃ before calcination.
Calcining at 250-350 ℃ is selected from S5, crystals can be damaged along with high temperature because the specific surface area of nano zinc oxide is smaller at higher temperature, the average particle size of the zinc oxide calcined at 300 ℃ at low temperature is 10-20nm, the average particle size of the zinc oxide calcined at 800 ℃ at high temperature is more than 100nm, the specific surface area is 5m2In g, the low specific surface area of the high-temperature calcination does not meet the high specific surface requirements for cosmetic requirements.
The high-transparency nano zinc oxide is characterized in that the transparency is 90-95%, and the specific surface area is not less than 45 square meters per gram.
The application of the high-transparency nano zinc oxide is the application in the field of cosmetics;
preferably, the cosmetic field is in particular the field of sunscreen cosmetics.
The invention has the beneficial effects that:
according to the invention, a zinc chloride solution and an ammonium bicarbonate solution are reacted at normal temperature to obtain basic zinc carbonate precipitate, and then the basic zinc carbonate precipitate is calcined at 250-300 ℃ to obtain the nano zinc oxide with the transparency of 90-95% and the specific surface area of more than or equal to 45 square meters per gram, so that the nano zinc oxide can be applied to the field of cosmetics. The nano zinc oxide of the invention also has the characteristics of fine particles and high purity.
Detailed Description
Example 1
S1, preparation of a crude zinc chloride solution: adding 65% zinc hypoxide into 31% hydrochloric acid to react until the pH value is 3.5, adding barium chloride, and filtering;
s2, preparing a refined zinc chloride solution: heating the crude zinc chloride solution prepared in the step S1 to 85 ℃, adding an impurity removing agent to remove iron and manganese, filtering, cooling the filtrate to 30 ℃, adding a mixed solution of sodium ferulate and thiourea, and filtering;
wherein the ratio of the sodium ferbamate to the thiourea is 2:1, and the addition amount is 15 times of the total weight of the nickel solution.
S3, preparation of crude basic zinc carbonate: cooling the refined zinc chloride solution prepared in the step S2 to normal temperature, adding an ammonium bicarbonate solution with the weight ratio of 1.15 times, reacting until the pH value is 6.5, filtering to obtain basic zinc carbonate precipitate, recovering and concentrating the filtrate which is ammonium chloride mother liquor;
s4, preparation of refined basic zinc carbonate: washing the basic zinc carbonate precipitate prepared in the step S3 with pure water until the conductivity is 50 us/cm;
s5, preparation of nano zinc oxide: and (4) drying the refined basic zinc carbonate prepared in the step (S4), calcining at 300 ℃ for 1h, and cooling to obtain the high-transparency nano zinc oxide.
Example 2
S1, preparation of a crude zinc chloride solution: adding 64% zinc hypoxide into 31% hydrochloric acid to react until the pH value is 3.7, adding barium chloride, and filtering;
s2, preparing a refined zinc chloride solution: heating the crude zinc chloride solution prepared in the step S1 to 80 ℃, adding an impurity removing agent to remove iron and manganese, filtering, cooling the filtrate to 25 ℃, adding a mixed solution of sodium ferulate and thiourea, and filtering;
wherein the ratio of the sodium ferbamate to the thiourea is 2:1, and the addition amount is 18 times of the total amount of the nickel in the solution by weight.
S3, preparation of crude basic zinc carbonate: cooling the refined zinc chloride solution prepared in the step S2 to normal temperature, adding 3% ammonium bicarbonate solution with the weight ratio of 1.1 times, reacting until the pH value is 6.5, filtering to obtain basic zinc carbonate precipitate, wherein the filtrate is ammonium chloride mother liquor, and recovering and concentrating;
s4, preparation of refined basic zinc carbonate: washing the basic zinc carbonate precipitate prepared in the step S3 with pure water until the conductivity is 50 us/cm;
s5, preparation of nano zinc oxide: and (4) drying the refined basic zinc carbonate prepared in the step S4, calcining at 250 ℃ for 1h, and cooling to obtain the high-transparency nano zinc oxide.
Example 3
S1, preparation of a crude zinc chloride solution: adding zinc hypoxide into hydrochloric acid to react until the pH value is 4, adding barium chloride, and filtering;
s2, preparing a refined zinc chloride solution: heating the crude zinc chloride solution prepared in the step S1 to 90 ℃, adding an impurity removing agent to remove iron and manganese, filtering, cooling the filtrate to 20 ℃, adding a mixed solution of sodium ferulate and thiourea, and filtering;
wherein the ratio of the sodium ferbamate to the thiourea is 2:1, and the addition amount is 20 times of the total weight of the nickel solution.
S3, preparation of crude basic zinc carbonate: cooling the refined zinc chloride solution prepared in the step S2 to normal temperature, adding an ammonium bicarbonate solution with the weight ratio of 1.2 times, reacting until the pH value is 7, filtering to obtain basic zinc carbonate precipitate, recovering and concentrating the filtrate which is ammonium chloride mother liquor;
s4, preparation of refined basic zinc carbonate: washing the basic zinc carbonate precipitate prepared in the step S3 with pure water until the conductivity is 50 us/cm;
s5, preparation of nano zinc oxide: and (4) drying the refined basic zinc carbonate prepared in the step S4, calcining at 350 ℃ for 1h, and cooling to obtain the high-transparency nano zinc oxide.
Example 4
S1, preparation of a crude zinc chloride solution: adding zinc hypoxide into hydrochloric acid to react until the pH value is 4, adding barium chloride, and filtering;
s2, preparing a refined zinc chloride solution: heating the crude zinc chloride solution prepared in the step S1 to 90 ℃, adding an impurity removing agent to remove iron and manganese, filtering, adding excessive zinc powder, and filtering;
s3, preparation of crude basic zinc carbonate: cooling the refined zinc chloride solution prepared in the step S2 to normal temperature, adding an ammonium bicarbonate solution with the weight ratio of 1.2 times, reacting until the pH value is 7, filtering to obtain basic zinc carbonate precipitate, recovering and concentrating the filtrate which is ammonium chloride mother liquor;
s4, preparation of refined basic zinc carbonate: washing the basic zinc carbonate precipitate prepared in the step S3 with pure water until the conductivity is 50 us/cm;
s5, preparation of nano zinc oxide: and (4) drying the refined basic zinc carbonate prepared in the step (S4), calcining at 300 ℃ for 1h, and cooling to obtain the high-transparency nano zinc oxide.
Comparative example 1
The reaction temperature in S3 was 50 ℃ as in example 1.
Comparative example 2
The calcination temperature in S5 was 400 ℃ as in example 1.
Comparative example 3
S2, cooled to 50 ℃, and then added with the mixed solution of sodium thiram and thiourea, the same as in example 1.
Comparative example 4
S2 was added the sodium feramete solution, the rest being example 1.
Comparative example 5
S2 was added a thiourea solution, as in example 1.
Comparative example 6
Example 1 was repeated except that the mixed solution of sodium ferulate and thiourea in S2 was used in a ratio of 1: 1.
Comparative example 7
The same as in example 1 is applied to the mixed solution of sodium dimethyl dithiocarbamate and thiourea at S2, wherein the ratio of sodium dimethyl dithiocarbamate to thiourea is 3: 1.
The content of transparent zinc oxide and the content of arsenic, lead, cadmium and the like in the finished product are measured by the national standard (GB/T19589-2004) method of nano zinc oxide, and are shown in Table 1. Clarity measurements were made according to the Australian sunscreen standard (S2604-1983) method, as shown in Table 2.
TABLE 1
TABLE 2
| Item | Average particle diameter, nm | Degree of transparency% | Specific surface area, m2/g |
| Example 1 | 12 | 94.89 | 69.25 |
| Example 2 | 15 | 94.56 | 65.35 |
| Example 3 | 17 | 92.37 | 55.89 |
| Example 4 | 19 | 91.57 | 66.35 |
| Comparative example 1 | 48 | 80.12 | 44.37 |
| Comparative example 2 | 61 | 78.68 | 40.36 |
| Comparative example 3 | 18 | 86.67 | 68.3 |
| Comparative example 4 | 15 | 77.67 | 67.6 |
| Comparative example 5 | 17 | 75.46 | 65.4 |
| Comparative example 6 | 14 | 89.48 | 66.5 |
| Comparative example 7 | 16 | 93.23 | 67.3 |
As can be seen from Table 1, the nano high-transparency zinc oxide product prepared by the method provided by the invention meets GB/T19589-2004. As shown in Table 2, the nano high-transparency zinc oxide product prepared by the method provided by the invention has the average particle size of 10-20nm, the transparency of 91-95% and the specific surface area of more than or equal to 45m2(ii) in terms of/g. From example 4, it can be seen that the removal of impurities by using zinc powder can achieve better technical effects, but the sodium ferulate and thiourea solutions are lower in cost. By comparing comparative examples 1 and 2 with example 1, it was found that increasing the reaction temperature in S3 and the calcination temperature in S5 increased the zinc oxide content in the product, but resulted in increased product particle size, decreased transparency, and decreased specific surface area. As shown in comparative examples 3 to 7, the purity of zinc oxide was affected and impurities increased without removing impurities from the mixed solution of sodium ferulate and thiourea, thereby decreasing the transparency. The single thiourea or sodium ferulate solution has poor impurity removal effect, which indicates that the two have synergistic effectThe impurity removal effect can be greatly improved, so that the purity of the zinc oxide is improved, the particle size is reduced, and the transparency is improved. Comparative example 3 shows that temperature has a great influence on the effect of removing impurities and thus on the transparency. The temperature rise is not beneficial to the impurity removal effect of the sodium dimethyl dithiocarbamate and the thiourea solution. The temperature at which sodium ferometalate and thiourea are produced to produce the best results in the zinc chloride solution is 20-30 c, with the optimum ratio being 2: 1.
Finally, it should be emphasized that the above-described preferred embodiments of the present invention are merely examples of implementations, rather than limitations, and that many variations and modifications of the invention are possible to those skilled in the art, without departing from the spirit and scope of the invention.
Claims (8)
1. A preparation method of high-transparency nano zinc oxide is characterized by comprising the following specific steps:
s1, preparation of a crude zinc chloride solution: adding zinc hypoxide into hydrochloric acid to react until the pH value is 3-4, adding barium chloride, and filtering;
s2, preparing a refined zinc chloride solution: removing impurities from the crude zinc chloride solution prepared in the step S1; the impurity removing agent used for removing the impurities is a mixed solution of sodium dimethyl dithiocarbamate and thiourea; the ratio of the sodium feramete to the thiourea is 2:1, and the impurity removal temperature is 20-30 ℃;
s3, preparation of crude basic zinc carbonate: adding an ammonium bicarbonate solution, cooling to 20-30 ℃, reacting the refined zinc chloride solution prepared in the step S2 until the pH value is 6-7, filtering to obtain basic zinc carbonate precipitate, recovering and concentrating the filtrate which is an ammonium chloride mother liquor;
s4, preparation of refined basic zinc carbonate: washing the basic zinc carbonate precipitate prepared in the step S3 with pure water, wherein the pure water is pure water at 70 ℃;
s5, preparation of nano zinc oxide: drying, calcining and cooling the refined basic zinc carbonate prepared in the step S4 to obtain high-transparency nano zinc oxide;
the transparency of the high-transparency nano zinc oxide is 90-95%.
2. The method for preparing high-transparency nano zinc oxide according to claim 1, wherein the amount of hydrochloric acid added into S1 is 31% and the amount of zinc hypoxide is 55-65% by weight.
3. The method for preparing high-transparency nano zinc oxide according to claim 1, wherein the mass fraction of the ammonium bicarbonate solution in S3 is 3%.
4. The method for preparing high-transparency nano zinc oxide according to claim 1, wherein the amount of the ammonium bicarbonate solution in S3 is 1.1-1.2 times of the weight of the refined zinc chloride solution.
5. The method for preparing high-transparency nano zinc oxide according to claim 1, wherein the washing is carried out until the conductivity of washing water is 10-50 us/cm.
6. The preparation method of high-transparency nano zinc oxide according to claim 1, wherein the calcination temperature in S5 is 250-350 ℃, and the calcination time is 1-1.5 h.
7. The nano zinc oxide prepared by the preparation method of any one of claims 1 to 6, wherein the transparency is 90-95%.
8. Use of nano zinc oxide according to claim 7, characterized in that it is a use in the field of cosmetics, in particular sun protection cosmetics.
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Citations (5)
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|---|---|---|---|---|
| CN1413911A (en) * | 2002-09-30 | 2003-04-30 | 吴晓东 | Process for preparing high-purity Nano-class zinc oxide |
| CN104591259A (en) * | 2015-02-09 | 2015-05-06 | 黄有余 | Engraftment type nano-zinc oxide and production process thereof |
| CN106219594A (en) * | 2016-08-03 | 2016-12-14 | 王凯 | A kind of preparation method of nano zine oxide |
| CN107376189A (en) * | 2017-07-06 | 2017-11-24 | 武汉强丰新特科技有限公司 | A kind of preparation method and application of heavy metal chelant |
| CN110205482A (en) * | 2019-05-28 | 2019-09-06 | 西北矿冶研究院 | Comprehensive recovery method of cobalt-removing slag of zinc smelting organic matter |
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Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1413911A (en) * | 2002-09-30 | 2003-04-30 | 吴晓东 | Process for preparing high-purity Nano-class zinc oxide |
| CN104591259A (en) * | 2015-02-09 | 2015-05-06 | 黄有余 | Engraftment type nano-zinc oxide and production process thereof |
| CN106219594A (en) * | 2016-08-03 | 2016-12-14 | 王凯 | A kind of preparation method of nano zine oxide |
| CN107376189A (en) * | 2017-07-06 | 2017-11-24 | 武汉强丰新特科技有限公司 | A kind of preparation method and application of heavy metal chelant |
| CN110205482A (en) * | 2019-05-28 | 2019-09-06 | 西北矿冶研究院 | Comprehensive recovery method of cobalt-removing slag of zinc smelting organic matter |
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| 次氧化锌的资源化研究;庄永等;《当代化工》;20190531;第980-984页 * |
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