CN111777094B - Preparation method of nanoscale zinc oxide with controllable pile ratio - Google Patents
Preparation method of nanoscale zinc oxide with controllable pile ratio Download PDFInfo
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- CN111777094B CN111777094B CN202010665454.6A CN202010665454A CN111777094B CN 111777094 B CN111777094 B CN 111777094B CN 202010665454 A CN202010665454 A CN 202010665454A CN 111777094 B CN111777094 B CN 111777094B
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Abstract
The invention relates to a preparation method of nanoscale zinc oxide with controllable bulk density, which comprises the following steps: step 1, performing chemical reaction on zinc sulfate and alkali A at 50-90 ℃, controlling the pH value at the end of the reaction to be 7-12, and filtering to obtain filtrate A; step 2, carrying out multiple-effect separation and concentration on the filtrate A, and filtering to obtain a zinc hydroxide filter cake; step 3, rinsing the zinc hydroxide filter cake for three times to obtain a filter cake D; and 4, adding the rinsed filter cake D into a dispersion system, adding alkali B to control the alkalinity of the dispersion system to be more than 1.5g/L, stirring and hydrolyzing for 30-120 min at the temperature of 30-80 ℃ and at the rotating speed of 50-70 r/min, filtering to obtain a zinc oxide filter cake, and drying to obtain the nanoscale zinc oxide. The nano zinc oxide prepared by the invention has wider bulk ratio range and can be adjusted within the bulk ratio range of 0.4 g/ml-1.2 g/ml as required.
Description
Technical Field
The invention belongs to the field of nano zinc oxide preparation, and particularly relates to a preparation method of nano zinc oxide with controllable stack ratio.
Background
Different types of zinc oxide can be obtained due to different synthesis conditions of zinc oxide, but the nanometer zinc oxide has the characteristics of surface effect, volume effect, high transparency, high dispersibility and the like which are not possessed by macroscopic objects due to the fact that the particle size of the nanometer zinc oxide is smaller than 100nm, so that the nanometer zinc oxide has important value in many fields such as rubber, ceramics, chemical engineering, electronics, biology, medicines and the like, has the property which cannot be replaced by common zinc oxide, and becomes a research hotspot at present.
However, in industrial application, different application fields and different applications have different stacking ratio requirements on the nano zinc oxide, for example, the stacking ratio of the nano zinc oxide used as feed is preferably more than 0.7, and the stacking ratio of the nano zinc oxide used in the rubber industry is preferably 0.4-0.8; however, the existing preparation method of nano zinc oxide has a narrow range of bulk ratio, and even if parameter conditions are adjusted, the range of bulk ratio of the prepared nano zinc oxide cannot be changed, so that the production of nano zinc oxide with different bulk ratios has respective methods and devices, the method universality is poor, the zinc oxide with different bulk ratios can only be processed by different devices, the device utilization rate is low, the range of bulk ratio cannot be controlled and adjusted according to needs, and the method cannot be better suitable for the market.
Disclosure of Invention
The invention aims to overcome the defects of the prior art and provides a preparation method of nanoscale zinc oxide with controllable stack ratio.
In order to achieve the purpose, the technical scheme adopted by the invention is as follows:
a preparation method of nanoscale zinc oxide with controllable stack ratio specifically comprises the following steps:
step 1, preparing zinc hydroxide: performing chemical reaction on zinc sulfate and alkali A at 50-90 ℃, controlling the pH value of a reaction end point to be 7-12, and filtering to obtain filtrate A;
step 2, impurity removal: carrying out multi-effect separation and concentration on the filtrate A, recovering sodium sulfate, obtaining zinc hydroxide with the solid content of more than 95%, and filtering to obtain a zinc hydroxide filter cake;
and step 3, rinsing: rinsing the zinc hydroxide filter cake for three times to obtain a filter cake D;
step 4, hydrolysis modification: and (2) adding the rinsed filter cake D into an alkali liquor B for dispersion according to the mass ratio of the feed liquid to the alkali liquor of 2.
Further, the specific operation steps for preparing the zinc hydroxide in the step 1 are as follows: firstly, according to Zn 2+ And OH - Mixing a zinc sulfate solution with an alkali liquor A, stirring and reacting at 50-90 ℃ for 20-40 min, then, continuously adding the alkali liquor A to the pH value of 7-12 in the stirring process, then, continuously stirring for 20-40 min, ending the reaction, and filtering to obtain a filtrate A.
Furthermore, the concentration of the zinc sulfate solution is 160-170g/L, and the mass concentration of the alkali liquor A is 32-50%.
Further, the pH value of the zinc sulfate solution is 4-5, and the lead content in the zinc sulfate solution is less than or equal to 2ppm; the content of the separator is less than or equal to 1ppm; the arsenic content is less than or equal to 1ppm.
Further, the filtrate E obtained in step 4 is reused in the dispersion.
Furthermore, the material liquid mass ratio in the rinsing process is 1.
Furthermore, the rinsing in step 3 comprises the following specific steps:
rinsing for the first time: adding the zinc hydroxide filter cake into the rinsing liquid A, stirring and dispersing for 20min, and filtering to obtain a filter cake B and a filtrate B;
and (3) rinsing for the second time: adding the filter cake B into the rinsing liquid B, stirring and dispersing for 20min, and filtering to obtain a filter cake C and a filtrate C;
and (3) rinsing for the third time: adding the filter cake C into the rinsing liquid C, stirring and dispersing for 20min, and filtering to obtain a filter cake D and a filtrate D; the rinsing liquid C is water, the rinsing liquid B is filtrate D, and the rinsing liquid A is filtrate C.
Further, adding alkali A into the filtrate B, adjusting the concentration of the alkali liquor, and reusing the filtrate B as the alkali liquor A in the step 1.
Further, in the step 3, when the alkalinity of the dispersion system is controlled to be 5-10 g/L and the temperature of hydrolysis modification is controlled to be 70-80 ℃, the bulk ratio of the prepared nano zinc oxide is 0.8-1.0;
when the alkalinity of the dispersion system is controlled to be 1.5-2.5 g/L and the temperature of hydrolysis modification is controlled to be 50-70 ℃, the bulk ratio of the prepared nano zinc oxide is 0.4-0.8.
Further, in the step 1, sodium hydroxide or potassium hydroxide is adopted as the alkali A;
in the step 4, in the hydrolysis modification, the alkali B used in the alkali liquor B comprises one or more of sodium carbonate, ammonia water, sodium hydroxide, potassium hydroxide and potassium carbonate.
The principle of the partial chemical reaction involved in the invention is as follows:
(1)ZnSO 4 +OH - ＝Na 2 SO 4 +Zn(OH) 2 ；
(2)
compared with the prior art, the invention has the advantages that:
the invention takes zinc sulfate as raw material, generates zinc hydroxide through the reaction with alkali, and then removes sodium sulfate through multiple rinsing, and prepares nano zinc oxide through hydrolysis modification, and the method is adopted, the prepared nano zinc oxide has wider bulk ratio range, and the size of the bulk ratio can be regulated and controlled through adjusting the reaction conditions in the hydrolysis modification process, thereby realizing that the bulk ratio of the nano zinc oxide is regulated and controlled within the range of 0.4 g/ml-1.2 g/ml according to the requirements.
Drawings
FIG. 1 is a process flow diagram of one embodiment of the present invention.
Detailed Description
The present invention will be described in further detail with reference to examples.
Example 1
A preparation method of nanoscale zinc oxide with controllable bulk density is characterized by comprising the following steps:
step 1, preparing zinc hydroxide: performing chemical reaction on zinc sulfate and alkali A (in the embodiment, the alkali A adopts sodium hydroxide), controlling the pH value of a reaction end point to be 10, and filtering to obtain filtrate A;
the specific operation steps for preparing the zinc hydroxide are as follows: firstly, according to Zn 2+ And OH - Mixing a zinc sulfate solution with a concentration of 162g/L and an alkali liquor A with a mass concentration of 40% (in this embodiment, the alkali liquor A is a NaOH solution), stirring and reacting at 70 ℃ for 30min, then, continuously adding the alkali liquor A to a pH value of 10 during stirring, then, continuously stirring for 30min, finishing reaction, and filtering to obtain a filtrate A; the pH value of the zinc sulfate solution is 4.5, and the lead content in the zinc sulfate solution is less than or equal to 2ppm; the content of the separator is less than or equal to 1ppm; the arsenic content is less than or equal to 1ppm;
step 2, impurity removal: carrying out multi-effect separation and concentration on the filtrate A, recovering sodium sulfate, obtaining a zinc hydroxide solution with the solid content of more than 95%, and filtering to obtain a zinc hydroxide filter cake;
and step 3, rinsing: rinsing the zinc hydroxide filter cake for three times to obtain a filter cake D;
the specific operation steps of rinsing are as follows:
rinsing for the first time: adding the zinc hydroxide filter cake into the rinsing liquid A according to the mass ratio of the feed liquid of 1;
and (3) rinsing for the second time: adding the filter cake B into the rinsing liquid B according to the material liquid mass ratio of 1;
and (3) rinsing for the third time: adding the filter cake C into the rinsing liquid C according to the mass ratio of the feed liquid to the rinsing liquid C of 1; the rinsing liquid C is water, the rinsing liquid B is filtrate D, and the rinsing liquid A is filtrate C;
the rinsing liquid C is water, the rinsing liquid B is filtrate D, and the rinsing liquid A is filtrate C; adding alkali into the filtrate B, and adjusting the concentration of the alkali liquor to obtain the alkali liquor A;
step 4, hydrolysis modification: adding the rinsed zinc hydroxide filter cake into a dispersion system (namely an alkali liquor B) according to the mass ratio of the feed liquid to 2:1, adding an alkali B (sodium hydroxide is adopted in the embodiment) into the dispersion system to control the alkalinity of the dispersion system to be 8g/L, stirring and hydrolyzing for 80min at the temperature of 75 ℃ and at the rotating speed of 60 revolutions/min, filtering to obtain a zinc oxide filter cake and a filtrate E, drying the obtained zinc oxide filter cake to obtain nanoscale zinc oxide, reusing the filtrate E obtained in the step 4 into the dispersion system, and controlling the particle size of the nano zinc oxide prepared in the embodiment to be 20-30nm; the bulk ratio is 0.8-1.0 g/ml, and the purity of the obtained nano zinc oxide is 95%; reaching the standard of feed-grade nano zinc oxide.
Example 2
A preparation method of nanoscale zinc oxide with controllable bulk density is characterized by comprising the following steps:
step 1, preparing zinc hydroxide: performing a chemical reaction on zinc sulfate and alkali A (in the embodiment, the alkali A is sodium hydroxide), controlling the pH value of a reaction end point to be 8, and filtering to obtain filtrate A;
the specific operation steps for preparing the zinc hydroxide are as follows: firstly, according to Zn 2+ And OH - Mixing a zinc sulfate solution with a concentration of 162g/L and an alkali liquor A with a mass concentration of 40% (in the embodiment, the alkali liquor A adopts a NaOH solution), stirring and reacting at 80 ℃ for 20min, then, continuously adding the alkali liquor A to a pH value of 8 during stirring, then, continuously stirring for 20min, finishing the reaction, and filtering to obtain a filtrate A; the pH value of the zinc sulfate solution is 4-5, and the lead content in the zinc sulfate solution is less than or equal to 2ppm; the content of the separator is less than or equal to 1ppm; the arsenic content is less than or equal to 1ppm;
step 2, impurity removal: carrying out multi-effect separation and concentration on the filtrate A, recovering sodium sulfate, obtaining zinc hydroxide with the solid content of more than 95%, and filtering to obtain a zinc hydroxide filter cake;
and step 3, rinsing: rinsing the zinc hydroxide filter cake for three times to obtain a filter cake D;
the specific operation steps of rinsing are as follows:
rinsing for the first time: adding the zinc hydroxide filter cake into the rinsing liquid A according to the mass ratio of the feed liquid of 1;
and (3) rinsing for the second time: adding the filter cake B into the rinsing liquid B according to the material liquid mass ratio of 1;
and (3) rinsing for the third time: adding the filter cake C into the rinsing liquid C according to the mass ratio of the feed liquid to the rinsing liquid C of 1; the rinsing liquid C is water, the rinsing liquid B is filtrate D, and the rinsing liquid A is filtrate C;
the rinsing liquid C is water, the rinsing liquid B is filtrate D, and the rinsing liquid A is filtrate C; adding alkali into the filtrate B, and adjusting the concentration of the alkali liquor to obtain the alkali liquor A;
step 4, hydrolysis modification: adding the rinsed zinc hydroxide filter cake into a dispersion system (namely alkali liquor B) according to the feed liquid mass ratio of 2; the filtrate E obtained in the step 4 is reused in the dispersion system, and the particle size of the nano zinc oxide prepared in the embodiment is 20-30nm; the bulk ratio is 0.8-1.0 g/ml, and the purity of the obtained nano zinc oxide is 95%; reaches the standard of feed-grade nano zinc oxide.
Example 3
A preparation method of nanoscale zinc oxide with controllable bulk density is characterized by comprising the following steps:
step 1, step 2, step 3 are the same as example 1;
and 4, adding the rinsed zinc hydroxide filter cake into a dispersion system (namely alkali liquor B) according to the feed liquid mass ratio of 2 to 1, controlling the alkalinity of the dispersion system to be 2.0g/L, stirring and hydrolyzing at 50 ℃ for 80min at the rotating speed of 60, filtering to obtain a zinc oxide filter cake and a filtrate E, drying the obtained zinc oxide filter cake to obtain nanoscale zinc oxide, and reusing the filtrate E obtained in the step 4 in the dispersion system.
The particle size of the nano zinc oxide prepared by the embodiment is 20-30nm; the bulk ratio is 0.4-0.8 g/ml, the purity of the obtained nano zinc oxide is 95%, and the nano zinc oxide can be applied to the rubber industry.
The embodiments described above are only preferred embodiments of the present invention and are not exhaustive of the possible implementations of the present invention. Any obvious modifications thereof, which would occur to one skilled in the art without departing from the principles and spirit of the invention, are to be considered as included within the scope of the following claims.
Claims (9)
1. A preparation method of nanoscale zinc oxide with controllable bulk density is characterized by comprising the following steps:
step 1, preparing zinc hydroxide: performing chemical reaction on zinc sulfate and alkali A at 50-90 ℃, controlling the pH value of a reaction end point to be 7-12, and filtering to obtain filtrate A;
in the step 1, sodium hydroxide or potassium hydroxide is adopted as the alkali A;
step 2, impurity removal: carrying out multi-effect separation and concentration on the filtrate A, recovering sodium sulfate, obtaining zinc hydroxide with the solid content of more than 95%, and filtering to obtain a zinc hydroxide filter cake;
and step 3, rinsing: rinsing the zinc hydroxide filter cake for three times to obtain a filter cake D;
step 4, hydrolysis modification: adding the rinsed filter cake D into an alkali liquor B for dispersion according to the mass ratio of the feed liquid of 2;
in the step 4, when the alkalinity of the dispersion system is controlled to be 5-10 g/L and the temperature of hydrolysis modification is controlled to be 70-80 ℃, the bulk ratio of the prepared nano zinc oxide is 0.8-1.0;
when the alkalinity of the dispersion system is controlled to be 1.5-2.5 g/L and the temperature of hydrolysis modification is controlled to be 50-70 ℃, the bulk ratio of the prepared nano zinc oxide is 0.4-0.8.
2. The method for preparing nanoscale zinc oxide with controllable bulk ratio according to claim 1,
the specific operation steps for preparing the zinc hydroxide in the step 1 are as follows: firstly, according to Zn 2+ And OH - Mixing a zinc sulfate solution with an alkali liquor A, stirring and reacting at 50-90 ℃ for 20-40 min, then, continuously adding the alkali liquor A to a pH value of 7-12 in the stirring process, then, continuously stirring for 20-40 min, finishing the reaction, and filtering to obtain a filtrate A.
3. The method for preparing nanoscale zinc oxide with controllable bulk ratio according to claim 2, wherein the concentration of zinc sulfate solution is 160-170g/L, and the mass concentration of alkali liquor A is 32-50%.
4. The preparation method of nanoscale zinc oxide with controllable bulk ratio according to claim 1, wherein in step 1, the pH of the zinc sulfate solution is 4-5, and the lead content in the zinc sulfate solution is less than or equal to 2ppm; the content of the barrier is less than or equal to 1ppm; the arsenic content is less than or equal to 1ppm.
5. The method for preparing nanoscale zinc oxide with controllable bulk ratio according to claim 1, wherein filtrate E obtained in step 4 is reused in the dispersion system.
6. The method for preparing nano-scale zinc oxide with controllable bulk ratio according to claim 1, wherein the mass ratio of the feed liquid in the rinsing process is 1.
7. The method for preparing nanoscale zinc oxide with controllable bulk ratio according to claim 6,
the specific operation steps of rinsing in the step 3 are as follows:
rinsing for the first time: adding a zinc hydroxide filter cake into the rinsing liquid A, stirring and dispersing for 20min, and filtering to obtain a filter cake B and a filtrate B;
and (3) rinsing for the second time: adding the filter cake B into the rinsing liquid B, stirring and dispersing for 20min, and filtering to obtain a filter cake C and a filtrate C;
and (3) rinsing for the third time: adding the filter cake C into the rinsing liquid C, stirring and dispersing for 20min, and filtering to obtain a filter cake D and a filtrate D; the rinsing liquid C is water, the rinsing liquid B is filtrate D, and the rinsing liquid A is filtrate C.
8. The method for preparing nanoscale zinc oxide with controllable stack ratio according to claim 7, wherein the filtrate B is added with alkali A, and after adjusting the concentration of alkali liquor, the filtrate B is reused as alkali liquor A in step 1.
9. The method for preparing nanoscale zinc oxide with controllable bulk ratio according to claim 1,
in the step 4, in the hydrolysis modification, the alkali B used in the alkali liquor B comprises one or more of sodium carbonate, ammonia water, sodium hydroxide, potassium hydroxide and potassium carbonate.
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Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102795659A (en) * | 2012-07-30 | 2012-11-28 | 西安理工大学 | Method for preparing rod-like zinc oxide nano-crystals |
| CN103159251A (en) * | 2011-12-15 | 2013-06-19 | 贵州省纳米材料工程中心 | Preparation method for modified transparent nano-zinc oxide sol |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103159251A (en) * | 2011-12-15 | 2013-06-19 | 贵州省纳米材料工程中心 | Preparation method for modified transparent nano-zinc oxide sol |
| CN102795659A (en) * | 2012-07-30 | 2012-11-28 | 西安理工大学 | Method for preparing rod-like zinc oxide nano-crystals |
Non-Patent Citations (2)
| Title |
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| 氢氧化锌制备饲料级氧化锌的新工艺研究;杨运;《饲料工业》;20081231;36-38 * |
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