CN102408115A - Method for controlling gel amount in white carbon black by using precipitation method - Google Patents
Method for controlling gel amount in white carbon black by using precipitation method Download PDFInfo
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- CN102408115A CN102408115A CN2011102416056A CN201110241605A CN102408115A CN 102408115 A CN102408115 A CN 102408115A CN 2011102416056 A CN2011102416056 A CN 2011102416056A CN 201110241605 A CN201110241605 A CN 201110241605A CN 102408115 A CN102408115 A CN 102408115A
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Abstract
The invention relates to a method for controlling the gel amount in white carbon black by using a precipitation method, which comprises the following steps of: (1) taking water glass (modulus: 3.1-3.65; specific gravity: 1.084-1.086), an acidifier (a dilute sulphuric acid with a mass concentration of 15%) and pure water as raw materials; (2) carrying out a reaction on the raw materials; and (3) carrying out washing and drying on the obtained product. In the step of reaction above, an electrolyte salt is added into a base solution for white carbon black reaction by using the precipitation method, so that the mass percentage of the electrolyte salt accounts for 1.2-3% of the water glass content of the base solution; and according to another scheme, in the step of reaction above, the electrolyte salt is added into the acidifier for white carbon black reaction by using the precipitation method, so that the mass percentage of the electrolyte salt accounts for 0.4-1.6% of the mass of the sulphuric acid. The gel amount generated in the process of reaction is reduced by using a method for adding the electrolyte salt in the process of reaction, so that generated particles are uniform, good in dispersity and easy to wash, and the reaction is easy to control and has the characteristics of simple method and good gel amount control effect.
Description
Technical field
The present invention relates to a kind of preparation technology of precipitated silica, i.e. the control method of gel content in the precipitated silica.
Background technology
In the prior art, it is raw material that water glass solution (sodium silicate solution) and sulfuric acid are adopted in the production of precipitated silica, generates silicon-dioxide and byproduct sulfite, its reaction formula: Na
2OMSiO
2+ H
2SO
4=MSiO
2+ Na
2SO
4+ H
2O, M is a modulus of water glass in the formula.The method for preparing precipitated white carbon black step is following: (1) raw material: water glass, modulus 3.1-3.65, proportion 1.085 ± 0.001; Souring agent: mass concentration 15% dilute sulphuric acid; Pure water.(2) reaction: bed material adds the 30%-80% that the water glass amount is total charging capacity, starts to stir to be warming up to 80 ± 5 ℃, begins to add mass concentration and be 15% sulfuric acid reaction; In 40 minutes reaction times, the pH value of suspension-s reaches 9-10, more simultaneously and flow to and add water glass and sulfuric acid in the reaction kettle; And keep the pH value constant; Remaining 70%-20% water glass was added with 55 minutes, and it is intact with remainder water glass total overall reaction in the reaction kettle to continue to add sulfuric acid with 30 minutes, and the pH value of suspension-s is transferred to 2-3.(3) washing, drying: the WHITE CARBON BLACK reaction suspension filters, washs through the barrier film plate-and-frame filter press, and filter cake carries out slurried through hollander, and the spray-dried machine of slurries is dry.
Precipitated silica all has gel more or less to generate in process of production; Fill in the precipitated silica that uses if gel content control is improper as reinforcing rubber; Will influence the dispersion of precipitated silica in rubber; Thereby the processing characteristics and the reinforcing property of mixing of rubber have been reduced; Had a strong impact on the quality of precipitated silica, yet no matter be through scrap build or to the change of correlated response conditions such as temperature of reaction, material concentration, reaction times, the gel content in the WHITE CARBON BLACK product all can not get effective control.
Summary of the invention
The objective of the invention is provides a kind of method simple to above-mentioned deficiency, and gel content is controlled the control method of gel content in the effective precipitated silica.
Technical solution of the present invention is: the control method of gel content in the precipitated silica, and step is following:
(1) raw material: water glass, modulus 3.1-3.65, proportion 1.085 ± 0.001; Souring agent: mass concentration is 15% dilute sulphuric acid; Pure water;
(2) reaction: bed material adds the 30%-80% that the water glass amount is total charging capacity, starts to stir to be warming up to 80 ± 5 ℃, begins to add concentration and be 15% sulfuric acid reaction; In 40 minutes reaction times, the pH value of suspension-s reaches 9-10, more simultaneously and flow to and add water glass and sulfuric acid in the reaction kettle; And keep the pH value constant; Remaining 70%-20% water glass was added with 55 minutes, and it is intact with remainder water glass total overall reaction in the reaction kettle to continue to add sulfuric acid with 30 minutes, and the pH value of suspension-s is transferred to 2-3;
(3) washing, drying: the WHITE CARBON BLACK reaction suspension filters, washs through the barrier film plate-and-frame filter press, and filter cake carries out slurried through hollander, and the spray-dried machine of slurries is dry;
Scheme one is in above-mentioned reaction, in precipitated silica reaction end liquid, adds electrolytic salt, and making electrolytic salt quality percentage composition is the 0.5%-10% of water glass content in the end liquid; Preferred electrolyte salt is the 1.2-3% of water glass content in the end liquid.
Another program is in above-mentioned reaction, joins electrolytic salt in the precipitated silica reaction souring agent, and making ionogen quality percentage composition is the 0.2-6% of sulfuric acid quality.Preferred electrolyte salt is the 0.4-1.6% of sour quality.It is more obvious that electrolytic salt is joined in the souring agent effect, greatly reduces the growing amount of gel in the precipitated silica reaction process, also further improved the quality of WHITE CARBON BLACK.
Described electrolytic salt is sodium sulfate, also can be other solubility electrolytic salts for example sodium-chlor, Repone K or vitriolate of tartar etc.
Advantage of the present invention is: only reduce the gel content that generates in the reaction process through the method for in reaction process, adding electrolytic salt, make the particle of generation even, good dispersivity; Be easy to washing; Make reaction be easy to control, it is simple to have method, gel content control good effectiveness.
To combine embodiment that embodiment of the present invention is described in further detail below.
Embodiment
Embodiment 1
Use 5m
3Enamel reaction still adds modulus 3.4, the water glass 1.8m of proportion 1.085
3, agitator, warming while stirring makes the temperature of water glass solution rise to 80 ℃, keeps constant temperature, uses that to add mass concentration in 40 minutes be that 15% dilute sulphuric acid reacts, and makes suspension-s terminal point pH value reach 9-10; Connect above-mentioned reaction, water glass and 15% dilute sulphuric acid also flow to dropping in the reaction, with 1.2m
3Water glass dripped with 55 minutes, and kept reaction process pH9-10 constant, and 80 ℃ of temperature are constant; Connect above-mentioned reaction, in reaction kettle, add acid separately, with 30 minutes the water glass total overall reaction that there is not reaction in the reaction kettle is finished, and the pH value of suspension-s is transferred to 3.Suspension-s filters mother liquor with box filter, and reaction mother liquor uses the barrier film plate-and-frame filter press to carry out desalination, washing.Filter cake carries out pulp with hollander, carries out drying with spray-drier.(not adding sodium sulfate)
Embodiment 2:
The control method of gel content in the precipitated silica: use 5m
3Enamel reaction still adds modulus 3.4, the water glass 1.8m of proportion 1.085
3, solid sodium sulfate 2.0kg; Agitator, warming while stirring makes the temperature of water glass solution rise to 80 ℃, keeps constant temperature, uses that to add mass concentration in 40 minutes be that 15% dilute sulphuric acid reacts, and makes the suspension-s endpoint pH reach 9-10; Connect above-mentioned reaction, water glass and mass concentration are 15% dilute sulphuric acid and flow to dropping in the reaction, with 1.2m
3Water glass dripped with 55 minutes, and kept reaction process pH9-10 constant, and 80 ℃ of temperature are constant; Connect above-mentioned reaction, in reaction kettle, add acid separately, with 30 minutes the water glass total overall reaction that there is not reaction in the reaction kettle is finished, and the pH value of suspension-s is transferred to 3; Suspension-s filters mother liquor with box filter, and reaction mother liquor uses the barrier film plate-and-frame filter press to carry out desalination, washing; Filter cake carries out pulp with hollander, carries out drying with spray-drier.
(this example and embodiment 1 different be at bed material 1.8m
3, modulus 3.4 adds the 2.0kg solid sodium sulfate in the water glass solution of proportion 1.085.)
Embodiment 3:
Different with embodiment 2 is at bed material 1.8m
3, modulus 3.4 adds the 2.8kg solid sodium sulfate in the water glass solution of proportion 1.085.
Embodiment 4
The control method of gel content in the precipitated silica is characterized in that using 5m
3Enamel reaction still adds modulus 3.4, the water glass 1.8m of proportion 1.085
3, agitator, warming while stirring makes the temperature of water glass solution rise to 80 ℃, keeps constant temperature, uses that to add mass concentration in 40 minutes be that 15% dilute sulphuric acid reacts, and makes the suspension-s endpoint pH reach 9-10; Connect above-mentioned reaction, water glass and mass concentration are 15% dilute sulphuric acid and flow to dropping in the reaction, with 1.2m
3Water glass dripped with 55 minutes, and kept reaction process pH9-10 constant, and 80 ℃ of temperature are constant; Connect above-mentioned reaction, in reaction kettle, add acid separately, with 30 minutes the water glass total overall reaction that there is not reaction in the reaction kettle is finished, and the pH value of suspension-s is transferred to 3.Suspension-s filters mother liquor with box filter, and reaction mother liquor uses the barrier film plate-and-frame filter press to carry out desalination, washing.Filter cake carries out pulp with hollander, carries out drying with spray-drier; Described mass concentration is that the content of sodium sulfate is 0.4% of sulfuric acid quality in 15% the dilute sulphuric acid.
(different with embodiment 1 is that used mass concentration is that 15% dilute sulphuric acid contains sodium sulfate, and the content of sodium sulfate is 0.4% of bright sulfur acid quality.)
Embodiment 5
The amount of different with embodiment 4 is sodium sulfate is 0.6% of a bright sulfur acid quality.
The detection technique index of embodiment WHITE CARBON BLACK is listed in the table below:
Can be found out that by the embodiment detected result embodiment 2,3 is for adding the method control gel content of electrolytic salt in end liquid, embodiment 4,5 is the method control gel content that in souring agent, adds electrolytic salt.More than two kinds of methods all can reach the purpose that reduces gel content in the precipitated silica, gel content is effectively controlled, from detected result, latter's effect is more obvious.In this routine precipitated silica the judgement of gel content be employed in the quantitative rubber unvulcanizate number not the quantity of dispersive white point characterize.
Embodiment 6
What this example and embodiment 2 were different is at bed material 1.8m
3, modulus 3.4 adds 2.0kg sodium-chlor in the water glass solution of proportion 1.085.
Embodiment 7
What this example and embodiment 2 were different is at bed material 1.8m
3, modulus 3.4 adds 2.0kg Repone K in the water glass solution of proportion 1.085.
Embodiment 8
What this example and embodiment 2 were different is at bed material 1.8m
3, modulus 3.4 adds the 2.0kg vitriolate of tartar in the water glass solution of proportion 1.085.
Embodiment 9
Used concentration that different with embodiment 4 is is that 15% dilute sulphuric acid contains sodium-chlor, and the content of sodium-chlor is 0.4% of bright sulfur acid quality.
Embodiment 10
Used concentration that different with embodiment 4 is is that 15% dilute sulphuric acid contains Repone K, and the content of Repone K is 0.4% of bright sulfur acid quality.
Embodiment 11
Used concentration that different with embodiment 4 is is that 15% dilute sulphuric acid contains vitriolate of tartar, and the content of vitriolate of tartar is 0.4% of bright sulfur acid quality.
Embodiment 12
The amount of different with embodiment 4 is sodium sulfate is 1% of a bright sulfur acid quality.
Embodiment 13
The amount of different with embodiment 4 is sodium sulfate is 1.6% of a bright sulfur acid quality.
Claims (6)
1. the control method of gel content in the precipitated silica, step is following:
(1) raw material: water glass, modulus 3.1-3.65, proportion 1.085 ± 0.001; Souring agent: mass concentration is 15% dilute sulphuric acid; Pure water;
(2) reaction: bed material adds the 30%-80% that the water glass amount is total charging capacity, starts to stir to be warming up to 80 ± 5 ℃, begins to add concentration and be 15% sulfuric acid reaction; In 40 minutes reaction times, the pH value of suspension-s reaches 9-10, more simultaneously and flow to and add water glass and sulfuric acid in the reaction kettle; And keep the pH value constant; Remaining 70%-20% water glass was added with 55 minutes, and it is intact with remainder water glass total overall reaction in the reaction kettle to continue to add sulfuric acid with 30 minutes, and the pH value of suspension-s is transferred to 2-3;
(3) washing, drying: the WHITE CARBON BLACK reaction suspension filters, washs through the barrier film plate-and-frame filter press, and filter cake carries out slurried through hollander, and the spray-dried machine of slurries is dry;
It is characterized in that in precipitated silica reaction end liquid, adding electrolytic salt, making electrolytic salt quality percentage composition is the 0.5%-10% of water glass content in the end liquid;
Or electrolytic salt joins in the precipitated silica reaction souring agent, and making ionogen quality percentage composition is the 0.2-6% of sulfuric acid quality.
2. according to the control method of gel content in the described precipitated silica of claim 1, it is characterized in that electrolytic salt is the 1.2-3% of water glass content in the end liquid.
3. according to the control method of gel content in the described precipitated silica of claim 1, it is characterized in that electrolytic salt is the 0.4-1.6% of sour quality.
4. according to the control method of gel content in the arbitrary described precipitated silica of claim 1-3, it is characterized in that electrolytic salt is sodium sulfate, sodium-chlor, Repone K or vitriolate of tartar.
5. according to the control method of gel content in the described precipitated silica of claim 4, it is characterized in that using 5m
3Enamel reaction still adds modulus 3.4, the water glass 1.8m of proportion 1.085
3, solid sodium sulfate 2.0kg or 2.8kg; Agitator, warming while stirring makes the temperature of water glass solution rise to 80 ℃, keeps constant temperature, uses that to add concentration in 40 minutes be that 15% dilute sulphuric acid reacts, and makes the suspension-s endpoint pH reach 9-10; Connect above-mentioned reaction, water glass and concentration are 15% dilute sulphuric acid and flow to dropping in the reaction, with 1.2m
3Water glass dripped with 55 minutes, and kept reaction process pH9-10 constant, and 80 ℃ of temperature are constant; Connect above-mentioned reaction, in reaction kettle, add acid separately, with 30 minutes the water glass total overall reaction that there is not reaction in the reaction kettle is finished, and the pH value of suspension-s is transferred to 3; Suspension-s filters mother liquor with box filter, and reaction mother liquor uses the barrier film plate-and-frame filter press to carry out desalination, washing; Filter cake carries out pulp with hollander, carries out drying with spray-drier.
6. according to the control method of gel content in the described precipitated silica of claim 4, it is characterized in that using 5m
3Enamel reaction still adds modulus 3.4, the water glass 1.8m of proportion 1.085
3, agitator, warming while stirring makes the temperature of water glass solution rise to 80 ℃, keeps constant temperature, uses that to add concentration in 40 minutes be that 15% dilute sulphuric acid reacts, and makes suspension-s terminal point pH value reach 9-10; Connect above-mentioned reaction, water glass and concentration are 15% dilute sulphuric acid and flow to dropping in the reaction, with 1.2m
3Water glass dripped with 55 minutes, and kept reaction process pH9-10 constant, and 80 ℃ of temperature are constant; Connect above-mentioned reaction, in reaction kettle, add acid separately, with 30 minutes the water glass total overall reaction that there is not reaction in the reaction kettle is finished, and the pH value of suspension-s is transferred to 3; Suspension-s filters mother liquor with box filter, and reaction mother liquor uses the barrier film plate-and-frame filter press to carry out desalination, washing; Filter cake carries out pulp with hollander, carries out drying with spray-drier; Described concentration is that the content of sodium sulfate is 0.4% or 0.6% of sulfuric acid quality in 15% the dilute sulphuric acid.
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Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102951649A (en) * | 2012-11-15 | 2013-03-06 | 北京橡胶工业研究设计院 | Preparation method of modified precipitated white carbon black |
| CN104291344A (en) * | 2014-10-28 | 2015-01-21 | 通化双龙化工股份有限公司 | Production method for white carbon black with high additive amount |
| CN106315598A (en) * | 2016-08-09 | 2017-01-11 | 确成硅化学股份有限公司 | Method for preparing high-dispersity white carbon black for radial tire |
| CN106477587A (en) * | 2015-08-25 | 2017-03-08 | 中国石油天然气股份有限公司 | The preparation method of polyolefin catalyst carrier silica gel |
| CN106829977A (en) * | 2017-03-30 | 2017-06-13 | 福建正盛无机材料股份有限公司 | A kind of preparation method of high oil absorption high-dispersion white carbon black |
| CN109052421A (en) * | 2018-10-11 | 2018-12-21 | 江西安德力高新科技有限公司 | A kind of preparation method of white carbon black |
| CN111017939A (en) * | 2020-01-14 | 2020-04-17 | 福建省三明正元化工有限公司 | Preparation method of high-dispersion silicon dioxide |
| CN112678838A (en) * | 2020-12-29 | 2021-04-20 | 无锡恒诚硅业有限公司 | Low rolling resistance precipitated silica, and preparation method and application thereof |
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Cited By (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102951649A (en) * | 2012-11-15 | 2013-03-06 | 北京橡胶工业研究设计院 | Preparation method of modified precipitated white carbon black |
| CN104291344A (en) * | 2014-10-28 | 2015-01-21 | 通化双龙化工股份有限公司 | Production method for white carbon black with high additive amount |
| CN106477587A (en) * | 2015-08-25 | 2017-03-08 | 中国石油天然气股份有限公司 | The preparation method of polyolefin catalyst carrier silica gel |
| CN106477587B (en) * | 2015-08-25 | 2019-03-12 | 中国石油天然气股份有限公司 | The preparation method of polyolefin catalyst carrier silica gel |
| CN106315598A (en) * | 2016-08-09 | 2017-01-11 | 确成硅化学股份有限公司 | Method for preparing high-dispersity white carbon black for radial tire |
| CN106315598B (en) * | 2016-08-09 | 2018-08-21 | 确成硅化学股份有限公司 | The preparation method of the high-dispersion white carbon black of one meridian line tyre |
| CN106829977A (en) * | 2017-03-30 | 2017-06-13 | 福建正盛无机材料股份有限公司 | A kind of preparation method of high oil absorption high-dispersion white carbon black |
| CN109052421A (en) * | 2018-10-11 | 2018-12-21 | 江西安德力高新科技有限公司 | A kind of preparation method of white carbon black |
| CN111017939A (en) * | 2020-01-14 | 2020-04-17 | 福建省三明正元化工有限公司 | Preparation method of high-dispersion silicon dioxide |
| CN111017939B (en) * | 2020-01-14 | 2023-10-24 | 福建省三明正元化工有限公司 | Preparation method of high-dispersion silicon dioxide |
| CN112678838A (en) * | 2020-12-29 | 2021-04-20 | 无锡恒诚硅业有限公司 | Low rolling resistance precipitated silica, and preparation method and application thereof |
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Application publication date: 20120411 |