CN1994880A - Process for preparing white carbon black using attapulgite clay - Google Patents
Process for preparing white carbon black using attapulgite clay Download PDFInfo
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- CN1994880A CN1994880A CN 200610161393 CN200610161393A CN1994880A CN 1994880 A CN1994880 A CN 1994880A CN 200610161393 CN200610161393 CN 200610161393 CN 200610161393 A CN200610161393 A CN 200610161393A CN 1994880 A CN1994880 A CN 1994880A
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- carbon black
- white carbon
- attapulgite clay
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- water glass
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Abstract
The invention discloses a white carbon black making method through concave-convex bar-shaped stone clay, which comprises the following steps: adopting concave-convex bar-shaped stone clay as raw material; proceeding roughing separation; grinding; allocating concave-convex bar-shaped stone powder into suspension; stirring the suspension to disperse; transmitting the suspension into autoclave; heating; adding condensed acid to dissolve; removing impurity; obtaining the slurry; filtering; washing; obtaining the filter pie; heating the filter pie to remove impurity again; neutralizing through acid; separating solid from liquid; drying the solid; grinding to obtain the product.
Description
Technical field
The invention belongs to non-metallic minerals deep processing field and technical field of inorganic chemical industry, relate to a kind of method of utilizing attapulgite clay to prepare white carbon black.
Background technology
White carbon black (that is: active silica) is a kind of broad-spectrum Inorganic Chemicals.Adopt conventional method to prepare white carbon black, need to consume a large amount of soda ash and acid, and complex manufacturing, production cost is higher.
In No. 02148523.2 application documents of Chinese patent, disclosing a kind of is the method for raw material production nano bar-shape active silica with the attapulgite clay.This method is at first carried out ore dressing to Attapulgite, dries pulverizing then, and then adopts method of pickling to make bar-shaped silicon-dioxide.
Though this method is compared with prior art, save the high temperature alkali fuse process, reduced production cost, because it adopts acid-soluble one-step, be difficult to removal of impurities after the acidleach, thereby the silicon-dioxide purity that makes is not high relatively; In addition, the sour molten process in this method is difficult to destroy the club shaped structure of attapulgite clay, so the bar-shaped silicon-dioxide that makes is active relatively low.
Summary of the invention
The objective of the invention is to overcome existing problem in the above-mentioned prior art, a kind of method of utilizing attapulgite clay to prepare white carbon black is provided.
Above-mentioned purpose of the present invention is achieved in that a kind of method of utilizing attapulgite clay to prepare white carbon black, and it has following steps:
A. be raw material with the attapulgite clay of exploiting out, this attapulgite clay is roughly selected and pulverized;
B. the concave and convex rod stone powder after pulverizing is mixed with suspension liquid, and this suspension liquid is carried out dispersed with stirring;
C. change above-mentioned suspension liquid over to reactor, under heating and agitation condition, add concentrated acid carry out acid molten, take off assorted, the acquisition slurries;
D. make above-mentioned slurries cooling, and these cooled slurries are carried out press filtration, washing, obtain filter cake;
E. to above-mentioned filter cake the heating and agitation condition under, the hydro-oxidation sodium solution carries out the molten reaction of alkali, the cooling press filtration obtain water glass;
F. above-mentioned water glass being carried out secondary takes off assorted;
G. the water glass that secondary is taken off after mixing carries out the acid neutralization, adopts press filtration with solid-liquid separation, and solids drying, abrasive dust promptly obtain the white carbon black powder.
The method of utilizing attapulgite clay to prepare white carbon black of the present invention, among the step a, attapulgite content should be not less than 50%, and attapulgite is crushed to 200 orders.
The method of utilizing attapulgite clay to prepare white carbon black of the present invention, among the step b, it is formulated that suspension liquid is pressed soil ratio 3: 1, and add the Sodium hexametaphosphate 99 dispersed with stirring at least 1 hour of 4～5% attapulgite clay amounts.
The method of utilizing attapulgite clay to prepare white carbon black of the present invention, among the step c, Heating temperature remains on 100 ℃, and acid is molten, take off assorted used concentrated acid is the vitriol oil, the consumption of the vitriol oil is controlled at the scope of 35～50% clay amounts, and acid is molten, take off assorted process kept 3 hours at least.
The method of utilizing attapulgite clay to prepare white carbon black of the present invention, in the steps d, it is to adopt pressure filter that slurries are carried out press filtration, filter cake washes with water three times at least.
The method of utilizing attapulgite clay to prepare white carbon black of the present invention, among the step e, Heating temperature remains on 100 ℃, concentration is that the consumption of 8% sodium hydroxide solution is controlled at 30～40% scope, the molten reaction process of alkali kept 2.5 hours at least, the control modulus of water glass is 3.2～3.4, and dilution water glass is to about 12 degree Beaume.
The method of utilizing attapulgite clay to prepare white carbon black of the present invention, among the step f, the sodium oxalate that adds 1～2% clay amount in water glass stirs evenly, 45 ℃ slowly add sulfuric acid or hydrochloric acid to pH value of solution value down is about 7.0, obtain white carbon black " crystal seed ", after 2 hours, continuation feeding water glass and sulfuric acid or hydrochloric acid pH value stabilization to terminal are warming up to 85 ℃ after reaction is finished and wore out 2 hours at 8-9 with the uniform temp ageing.The sulfuric acid of above-mentioned adding or hydrochloric acid are used acid for neutralizing, can select 25% sulfuric acid when neutralizing with acid employing sulfuric acid for use, can select 30% hydrochloric acid when neutralizing with acid employing hydrochloric acid for use.
The method of utilizing attapulgite clay to prepare white carbon black of the present invention among the step f, further adds dispersion agent.
The method of utilizing attapulgite clay to prepare white carbon black of the present invention, described dispersion agent are propyl carbinol, and the consumption of this propyl carbinol is controlled in 0.5～1% scope of water glass solution volume.
The method of utilizing attapulgite clay to prepare white carbon black of the present invention, in the step g, solids is 120 ℃ of oven dry down.
Description of drawings
Accompanying drawing is a processing step schematic flow sheet of the present invention.
Embodiment
The present invention is further described below in conjunction with drawings and Examples.
As can be seen, concrete steps of the present invention are as follows from accompanying drawing:
1. the exploitation of attapulgite clay, roughly select
Through roughly selecting, select the mineral that attapulgite arrives desired content after the attapulgite clay exploitation;
2. abrasive dust, making beating
Attapulgite is crushed to the granularity of regulation, is mixed with suspension liquid by certain soil ratio then, and add the Sodium hexametaphosphate 99 of attapulgite clay amount, continue dispersed with stirring;
Acid molten, take off assorted
Change above-mentioned suspension liquid over to reactor, under keeping 100 ℃, add sulfuric acid reaction;
4. press filtration, washing
After reaction is finished, wait the slurries cooling, use the pressure filter press filtration, filter cake washes with water three times;
5. the molten system water glass of alkali
Theoretically, sodium hydroxide concentration depends on the SiO in the attapulgite
2Content.In fact, often be mixed with non-laminate structure mineral and rhombspar, cristobalite etc. in the attapulgite clay, and have minute quantity setting silicon can be converted into unsetting SiO after their activated acid treatment
2, and this a part of inversion quantity is difficult to accurate quantification, therefore, with the increase of alkali consumption, the actual measurement modulus of water glass is diminishing, and is lower than theoretical modulus.The major cause that causes this difference is that setting silicon transforms not exclusively in the attapulgite clay.
The control modulus of water glass is between 3.2～3.4.
6. the water glass secondary takes off assorted
Through acid activation deferrization, magnesium, aluminium, the liquid of the molten filtration of alkali is water glass, and when modulus was 3.2～3.4, directly conduct prepared the mother liquor of white carbon black, but this mother liquor still contains a spot of Al
3+, Mg
2+, Fe
3+, Ca
2+, etc., the mixture of the moisture often Calucium Silicate powder of white carbon black that goes out with this mother liquor direct production, Magnesium Silicate q-agent, pure aluminium silicate, silicic acid swage, its product still can not reach the white carbon black target level of product quality fully at aspects such as Chemical Composition, rerum natura and product performance, structure constructions.Therefore, before the water glass production white carbon black, need that mother liquor is carried out secondary and take off assorted.Directly adding chemical processing agent (slightly acidic sodium oxalate solution) in the water glass production white carbon black, avoiding the reaction of foreign ion and other Chemical Composition to generate throw out, when filtration, diafiltration white carbon black slurry, be removed.
7. white carbon black is produced in the acid neutralization
Adopt gelling technique to produce white carbon black.At first the water glass that makes is diluted to about 12 degree Beaume, change reactor then over to, under 50 ℃ and agitation condition, slowly adding neutralization is about 7.0 with acid to pH value of solution value, obtain white carbon black " crystal seed ", put into water glass and sulphuric acid soln after ageing for some time simultaneously, the pH value stabilization is at 8-9 to terminal.
8. press filtration, washing
The white carbon black slurries that make after about three times of press filtration, washing, 120 ℃ of down oven dry, grind the white carbon black powder.
Following specific embodiment is to be raw material with Xuyi Jiangsu area attapulgite clay, adopt acid molten, take off assorted-alkali molten-sour neutral step prepares the nano level precipitated silica.
Its ultimate principle be the attapulgite mineral under high temperature and strong acid condition, metal ions such as magnesium, aluminium, iron are easy to stripping in the crystalline framework, have kept the silicon in the lattice, thereby can make white carbon black through reaction.
Embodiment 1:
Attapulgite is crushed to 200 orders, gets the 50g powder and add 150ml distilled water, stir and make suspension liquid, add the Sodium hexametaphosphate 99 of about 2g then, continued dispersed with stirring 1 hour; Change above-mentioned suspension liquid over to reaction vessel, under 100 ℃, add the sulfuric acid reaction 3h of 15ml; After reaction is finished, wait the slurries cooling, use vacuum filtration, filter cake washes with water three times; Change filter cake over to reaction vessel, add water 250ml, add 1g sodium oxalate and 16g sodium hydroxide while stirring, 100 ℃ are reacted 2h down.Behind vacuum filtration, filtrate changes reactor over to, adds 150ml distilled water simultaneously, and under 50 ℃ and agitation condition, slowly adding 25% sulfuric acid to pH value of solution value is about 7.0, obtains white carbon black " crystal seed ".Put into water glass and sulphuric acid soln simultaneously behind " crystal seed " ageing 2h, the pH value stabilization is at 8-9 to terminal.The white carbon black slurries that make behind about three times of vacuum filtration, washing, 120 ℃ of down oven dry, grind the white carbon black powder.
Embodiment 2:
Get 200 order concave and convex rod stone powder 50g and add 150ml distilled water, stir and make suspension liquid, add the Sodium hexametaphosphate 99 of about 2g then, continued dispersed with stirring 1 hour; Change above-mentioned suspension liquid over to reaction vessel, under 100 ℃, add the sulfuric acid reaction 3h of 18ml; After reaction is finished, wait the slurries cooling, use vacuum filtration, filter cake washes with water three times; Change filter cake over to reaction vessel, add water 250ml, add 1g sodium oxalate and 18g sodium hydroxide while stirring, 100 ℃ are reacted 2h down.Behind vacuum filtration, filtrate changes reactor over to, adds 150ml distilled water simultaneously, under 50 ℃ and agitation condition, slowly adding 30% hydrochloric acid to pH value of solution value is about 7.0, obtains white carbon black " crystal seed ", put into water glass and hydrochloric acid soln simultaneously after placing 2h, the pH value stabilization is at 8-9 to terminal.The white carbon black slurries that make behind about three times of vacuum filtration, washing, 120 ℃ of down oven dry, grind the white carbon black powder.
Embodiment 3:
Get 200 order concave and convex rod stone powder 50g and add 150ml distilled water, stir and make suspension liquid, add the Sodium hexametaphosphate 99 of about 2g then, continued dispersed with stirring 1 hour; Change above-mentioned suspension liquid over to reaction vessel, under 100 ℃, add the sulfuric acid reaction 3h of 18ml; After reaction is finished, wait the slurries cooling, use vacuum filtration, filter cake washes with water three times; Change filter cake over to reaction vessel, add water 250ml, add 1g sodium oxalate and 18g sodium hydroxide while stirring, 100 ℃ are reacted 2h down.Behind vacuum filtration, filtrate changes reactor over to, adds 150ml distilled water and 5ml propyl carbinol simultaneously, under 50 ℃ and agitation condition, slowly add 30% hydrochloric acid to terminal the pH value stabilization at 8-9.The white carbon black slurries that make behind about three times of vacuum filtration, washing, 120 ℃ of down oven dry, grind the white carbon black powder.
In following subordinate list, listed the check and analysis result of the white carbon black that the various embodiments described above make.
Subordinate list: each embodiment white carbon black check and analysis result
| Title | GB GB10507-89 | Example 1 | Example 2 | Example 3 |
| SiO 2(％) | ≥90 | 92 | 92.5 | 90.5 |
| Weight loss on heating (%) | 4.0～8.0 | 6.8 | 5.2 | 7.4 |
| Burning decrement (%) | 7.0 | 4.2 | 4.5 | 6.3 |
| The pH value | 5.0～8.0 | 7.3 | 6.8 | 7.2 |
| DBP value (cm 3/g) | 2.00～3.50 | 2.35 | 2.16 | 2.12 |
| Surface-area (m 2/g) | A：＞190 | 178 | 226 | 207 |
| B：161～190 | ||||
| C：136～160 | ||||
| D：106～135 | ||||
| E：71～105 |
The present invention utilizes attapulgite to be raw material, assorted and the molten silicon of highly basic are taken off in dissolving through high temperature strong acid, can produce the higher water glass of purity, water glass can make the white carbon black product that quality is good, added value is high by neutralization reaction, and the while also provides effective way for the comprehensive utilization of attapulgite.Compare with traditional white carbon black production technology, the present invention have raw materials cost low, be beneficial to removal of impurities, cut down the consumption of energy, characteristics such as good product quality.
Claims (10)
1, utilize attapulgite clay to prepare the method for white carbon black, it is characterized in that having following steps:
A. be raw material with the attapulgite clay of exploiting out, this attapulgite clay is roughly selected and pulverized;
B. the concave and convex rod stone powder after pulverizing is mixed with suspension liquid, and this suspension liquid is carried out dispersed with stirring;
C. change above-mentioned suspension liquid over to reactor, under heating and agitation condition, add concentrated acid carry out acid molten, take off assorted, the acquisition slurries;
D. make above-mentioned slurries cooling, and these cooled slurries are carried out press filtration, washing, obtain filter cake;
E. to above-mentioned filter cake the heating and agitation condition under, the hydro-oxidation sodium solution carries out the molten reaction of alkali, the cooling press filtration obtain water glass;
F. above-mentioned water glass being carried out secondary takes off assorted;
G. the water glass that secondary is taken off after mixing carries out the acid neutralization, adopts press filtration with solid-liquid separation, and solids drying, abrasive dust promptly obtain the white carbon black powder.
2, the method for utilizing attapulgite clay to prepare white carbon black as claimed in claim 1 is characterized in that, among the step a, attapulgite content is not less than 50%, and attapulgite is crushed to 200 orders.
3, the method for utilizing attapulgite clay to prepare white carbon black as claimed in claim 2 is characterized in that, among the step b, it is formulated that suspension liquid is pressed soil ratio 3: 1, and adds the Sodium hexametaphosphate 99 dispersed with stirring at least 1 hour of 4～5% attapulgite clay amounts.
4, the method for utilizing attapulgite clay to prepare white carbon black as claimed in claim 3, it is characterized in that, among the step c, Heating temperature remains on 100 ℃, acid is molten, take off assorted used concentrated acid is the vitriol oil, the consumption of the vitriol oil is controlled in the scope of 35～50% clay amounts, and acid is molten, take off assorted process kept 3 hours at least.
5, the method for utilizing attapulgite clay to prepare white carbon black as claimed in claim 4 is characterized in that, in the steps d, it is to adopt pressure filter that slurries are carried out press filtration, and filter cake washes with water three times at least.
6, the method for utilizing attapulgite clay to prepare white carbon black as claimed in claim 5, it is characterized in that, among the step e, Heating temperature remains on 100 ℃, concentration is that the consumption of 8% sodium hydroxide solution is controlled at 30～40% scope, the molten reaction process of alkali kept 2.5 hours at least, and the control modulus of water glass is at 3.2-3.4, and dilution water glass is to about 12 degree Beaume.
7, the method for utilizing attapulgite clay to prepare white carbon black as claimed in claim 6, it is characterized in that, among the step f, the sodium oxalate that adds 1～2% clay amount in water glass stirs evenly, 45 ℃ add down slowly 25% sulfuric acid to pH value of solution values is about 7.0, obtains the white carbon black crystal seed, with the uniform temp ageing after 2 hours, continuation feeding water glass and sulphuric acid soln pH value stabilization to terminal are warming up to 85 ℃ after reaction is finished and wore out 2 hours at 8-9.(25% of adding sulfuric acid is the acid of neutralization usefulness herein, and this neutralizing acid can be sulfuric acid or hydrochloric acid.)
8, the method for utilizing attapulgite clay to prepare white carbon black as claimed in claim 6 is characterized in that, among the step f, further adds dispersion agent.
9, the method for utilizing attapulgite clay to prepare white carbon black as claimed in claim 8 is characterized in that, described dispersion agent is a propyl carbinol, and the consumption of this propyl carbinol is controlled in 0.5～1% scope of water glass solution volume.
10, the method for utilizing attapulgite clay to prepare white carbon black as claimed in claim 7 is characterized in that, in the step g, solids is 120 ℃ of oven dry down.
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Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101306343B (en) * | 2007-11-14 | 2010-09-22 | 中国科学院南京土壤研究所 | Method for preparing water body dephosphorized granule adsorbent using attapulgite clay |
| CN101434393B (en) * | 2007-11-16 | 2010-11-10 | 辽宁科技大学 | Method for preparing nano-scale amorphous silica from attapulgite clay |
| CN101367960B (en) * | 2008-09-12 | 2010-12-29 | 江苏工业学院 | Preparation method for composite material of nano-concave-convex stick stone/silicon dioxide |
| CN101759191B (en) * | 2009-12-10 | 2011-10-19 | 云南天鸿高岭矿业有限公司 | Production process for preparing white carbon black by using halloysite |
| CN102284279A (en) * | 2010-06-18 | 2011-12-21 | 中国石油化工股份有限公司 | Attapulgite/silicon dioxide composite powder and preparation method thereof |
| CN102351207A (en) * | 2011-08-22 | 2012-02-15 | 中国科学院兰州化学物理研究所盱眙凹土应用技术研发中心 | Method for preparing nano attapulgite by solvothermal process |
| CN105254273A (en) * | 2015-09-21 | 2016-01-20 | 中科院广州能源所盱眙凹土研发中心 | Desulphurization and dephosphorization method of clay for electrode coatings |
| CN110773168A (en) * | 2019-11-04 | 2020-02-11 | 中国石油大学(华东) | Denitration catalyst, preparation method thereof and denitration method |
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2006
- 2006-12-26 CN CN200610161393XA patent/CN1994880B/en not_active Expired - Fee Related
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101306343B (en) * | 2007-11-14 | 2010-09-22 | 中国科学院南京土壤研究所 | Method for preparing water body dephosphorized granule adsorbent using attapulgite clay |
| CN101434393B (en) * | 2007-11-16 | 2010-11-10 | 辽宁科技大学 | Method for preparing nano-scale amorphous silica from attapulgite clay |
| CN101367960B (en) * | 2008-09-12 | 2010-12-29 | 江苏工业学院 | Preparation method for composite material of nano-concave-convex stick stone/silicon dioxide |
| CN101759191B (en) * | 2009-12-10 | 2011-10-19 | 云南天鸿高岭矿业有限公司 | Production process for preparing white carbon black by using halloysite |
| CN102284279A (en) * | 2010-06-18 | 2011-12-21 | 中国石油化工股份有限公司 | Attapulgite/silicon dioxide composite powder and preparation method thereof |
| CN102284279B (en) * | 2010-06-18 | 2013-02-27 | 中国石油化工股份有限公司 | Attapulgite/silicon dioxide composite powder and preparation method thereof |
| CN102351207A (en) * | 2011-08-22 | 2012-02-15 | 中国科学院兰州化学物理研究所盱眙凹土应用技术研发中心 | Method for preparing nano attapulgite by solvothermal process |
| CN105254273A (en) * | 2015-09-21 | 2016-01-20 | 中科院广州能源所盱眙凹土研发中心 | Desulphurization and dephosphorization method of clay for electrode coatings |
| CN110773168A (en) * | 2019-11-04 | 2020-02-11 | 中国石油大学(华东) | Denitration catalyst, preparation method thereof and denitration method |
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