CN1830815A - Method of preparing high purity iron oxide for soft magnet using titanium white by product ferrous sulphate - Google Patents
Method of preparing high purity iron oxide for soft magnet using titanium white by product ferrous sulphate Download PDFInfo
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- CN1830815A CN1830815A CN 200610018642 CN200610018642A CN1830815A CN 1830815 A CN1830815 A CN 1830815A CN 200610018642 CN200610018642 CN 200610018642 CN 200610018642 A CN200610018642 A CN 200610018642A CN 1830815 A CN1830815 A CN 1830815A
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Abstract
A process for preparing the high-purity iron oxide used as soft-magnetic material from the copperas, which is the by-product of Ti white powder, and ferrous sulfate includes such steps as removing impurities, two-step neutralizing, two-step oxidizing to obtain Fe3O4, filtering, baking and calcining. The technological parameters for said neutralizing and oxidizing steps are also disclosed.
Description
Technical field
The invention belongs to the soft magnetic materials production technical field, particularly use the method for preparing high purity iron oxide for soft magnet using titanium white by product ferrous sulphate.
Background technology
Soft magnetic ferrite is the important base mateiral of electronic industry, and ferric oxide accounts for 70% in its composition.China's soft magnetic ferrite output kept increasing fast since nineteen ninety.Producing soft magnetism at present is the Ruthner method with spray roasting mainly with ferric oxide, this method is suitable for hydrochloric acid system, raw material is Steel Mill's spent pickle liquor, this method advantage is that output is big, cost is relatively low, but be difficult to produce high-grade soft magnetism ferric oxide, so the ferric oxide major part that this method is produced is used for low and middle-grade ferrites.For satisfying the ferritic needs of high quality, Production By Sulfuric Acid Process purity height, active good ferric oxide have appearred, be used to make the high-grade ferrite of tool high magnetic permeability; This method is that production cost is higher with the production of sulfuric acid dissolution iron and steel scrap mostly.Substitute iron and steel scrap with titanium white by product ferrous sulfate (trade(brand)name green vitriol) and become in recent years research focus as raw material.
China's titanium white production nearly all adopts sulfuric acid process, the about four tons of green vitriols of titanium dioxide by-product per ton, and overwhelming majority heap is abandoned into waste residue, the harm environment.To replace iron and steel scrap as raw material production soft magnetism ferric oxide with it, must solve foreign matter content problem of higher such as green vitriol foreign matter content, particularly titanium, silicon, aluminium, calcium, magnesium, manganese, wherein magnesium and manganese even can be respectively up to 1~2%, so purification and impurity removal is a key problem in technology.Impurity such as titanium, silicon, aluminium, calcium can be removed with traditional method, and manganese and magnesium then are difficult for removing, and particularly manganese and iron are the symbiosis elements, and chemical property is very close, separate quite difficulty.Recrystallization method is adopted in traditional purification, purifies by the repeatedly recrystallization to green vitriol and purifies, and this method disadvantage is the energy consumption height, and the ferrous sulfate mother liquor of a large amount of impurity of enrichment can't utilize, and the yield of iron is low.Chinese patent " with the method for the titanium white by product ferrous sulfate production high-purity magnetic iron oxide " technology that (patent No. 00113589) provides is purified iron recovery ability about 50% just with recrystallization method.In the method that Chinese patent application " process for refining of byproduct ferrous sulfate of titanium dioxide " (application number 94105891) provides, although titanium impurity good purification, manganese and magnesium almost can't be removed.Chinese patent " preparation method of iron oxide red for soft-magnetic ferrite " (patent No. 00139210) is to add inhibitor at synthesis phase, metal ions such as magnesium are retained in filter demagging in the mother liquor, but the used raw material Mg content of this patent only is 0.20%, the illustration for preparing with high magnesium raw material is not provided, and do not see that explanation produces effect to demanganization, the index of relevant manganese content does not provide yet.Chinese patent application " a kind of preparation method of ferric oxide red powder " (application number 03150766) has been done to specialize in to demanganization, by adding the demanganize agent reaching the purpose of demanganization, but this method difficulty comparatively when washing of precipitate, SO
4 2-Be difficult to wash clean, the product behind the torch firing also need be removed SO through series of processes
4 2-, and the productive rate of its pilot scale is lower, and every cubic metre of volume is 15 kilograms of output products only, and production cost can't reduce.Up to the present, do not see that pair manganese and the significant method report of magnesium removal effect are arranged.
Summary of the invention
It is raw material that the technical problem to be solved in the present invention provides a kind of titanium white by product with the high magnesium of high manganese, the preparation soft magnetism that production cost is low, quality product the is high method of ferric oxide.
The present invention solves the problems of the technologies described above with following technical scheme:
Green vitriol by neutralization of two steps and oxidation, makes manganese and magnesium not stay in the solution with the iron precipitation behind purification and impurity removal, and washing is removed after filtration, and the precipitated Z 250 that is oxidized to of iron rule makes high purity ferric oxide after the oven dry calcining after filtration.
The neutralization of two steps with the correlated condition of oxidation is:
(1) is controlled at 50g~100gFe/ liter with preceding concentration in the ferrous sulfate feed liquid;
It is 0.20~0.50 that the neutralization of (2) one steps adds neutralizing agent control alkali ratio, and the alkali ratio is the ratio of weight with the total iron weight of solution of volatile salt; 20~60 ℃ of temperature;
(3) oxidation step end acidity pH value is controlled to be 3.0~5.5;
The alkali ratio that the neutralization of (4) two steps adds neutralizing agent is 1.2~2.0; The same oxidizing temperature of temperature;
(5) second oxidation end acidity pH value is controlled to be 6.0~8.0;
(6) oxidizing temperature is controlled to be 50~90 ℃.
The molysite deposition that manganese, magnesium make after separating is calcined 1~2h at 650~750 ℃.
The ferric oxide of the inventive method preparation contains Fe
2O
3Can reach more than 99.4%, major impurity content such as Si, Ca, Al, Ti, Mg, Na etc. are below 60ppm, and Mn content is less than 0.15%, SO
4 2-Content is less than 0.10%, and the every index of the chemical purity of product all is better than the index of the optimum grade YHT1 of the soft magnetic ferrite ferric oxide industry standard SJ/T10383-98 of the Ministry of Electronics Industry; Physical performance index also satisfies the requirement of soft magnetism with ferric oxide.Crystalline form as product is an alpha crystalline form, and median size is 0.4~0.8 μ, and primary particle size is about 0.1 μ, and specific surface area is 4~6m
2/ g, loose specific weight is 0.6~0.8g/cm
3
The present invention has following outstanding advantage:
(1) can use the high magnesium titanium white by product of high manganese green vitriol to be raw material, effectively solve the pollution of titanium white production waste residue and utilize problem.In the process of separating manganese, magnesium and iron, do not need any additives, both avoided introducing new impurity, reduced production cost again, quality product is higher than ministerial standard.
(2) technical process is shorter, the product purity height;
(3) traditional iron protocarbonate calcination method often accompanies gelationus Fe (OH) in the calcining precursor of preparation
2, there is crystal water inside, causes sedimentation and filtration washing difficulty, calcining temperature up to 850 ℃ still difficulty eliminate crystal water; And the calcining precursor of the present invention's preparation is the Fe by the crystalization of crystal seed guiding generation
3O
4Precipitation has been avoided above shortcoming, is easy to filtration washing, and calcining temperature gets final product at 650~750 ℃, has kept the product activity preferably.
Description of drawings
Fig. 1 is the method process flow diagram of the present invention with preparing high purity iron oxide for soft magnet using titanium white by product ferrous sulphate.
Embodiment
The present invention mainly removes important impurity such as Ti, Si, Al and Cu, Zn, beavy metal impurities such as Pb, Ni in the purification and impurity removal stage of raw material green vitriol, removes and impurity Mn and Mg still stay the operation of the medium back of solution again.
The raw material green vitriol is joined the middle stirring and dissolving of hot water (about 80 ℃ of temperature) of regulating PH ≈ 2 with a small amount of sulfuric acid, control Fe
2+Concentration is 100~140g/L, presses green vitriol molten heavy 1% then and adds iron filings, in 80 ℃ of left and right sides insulation reaction a few hours, is elevated to 4.5~5.5 up to pH value, adds a certain amount of deionized water then solution Fe
2+Be diluted to 50-100g/L, simultaneously can reduce to 60~70 ℃ to temperature, adding concentration by green vitriol molten heavy 0.01~0.05% again is that (polyacrylamide) flocculation agent of 0.05% stirred 2~5 minutes, leave standstill can filter in 2~3 hours the green copperas solution of clear.Mainly by removing with oxidation style technology in two steps, its principle is for Mn and Mg impurity: when one goes on foot neutralization reaction, and (the NH of adding
4)
2CO
3Fe is being precipitated as FeCO
3The time, Mn and Mg also can form MnCO
3And MgCO
3Coprecipitation gets off, and following reaction mainly takes place when carrying out the first step oxidation subsequently:
At the first step oxidation stage, FeCO
3Become Fe through hydrolysis oxidation
3O
4Form crystal seed, and a part of FeSO that is not neutralized
4Then be oxidized to FeOOH, produce H simultaneously
2SO
4, the H that reaction generates
2SO
4With MnCO
3Or MgCO
3Reaction generates MnSO
4Or MgSO
4, Mn and Mg impurity are stayed in the solution; In second step and oxidation stage, oxidation limit, limit adds neutralizing agent, this moment under the guiding of crystal seed, Fe
2+Constantly precipitated, oxide deposition on nucleus, Mn
2+And Mg
2+Though also have the part deposition, have lot of F e in reaction system
2+Under the environment of (manganese magnesium relatively), Mn
2+And Mg
2+Can be by Fe
2+Cement out, thereby make that Mn and Mg continue again to stay in the solution again, by the time Fe
2+Deposit to concentration gradually more and more hour, Mn
2+, Mg
2+With Fe
2+The effect that co-precipitation takes place also weakens gradually, at the system pH value less than 8 o'clock because the long-pending principle of content, Mn
2+And Mg
2+Almost can not be neutralized agent and precipitate, thereby reach Mn, Mg and the isolating purpose of Fe.This method can make the manganese foreign matter content be reduced in the product below 0.15% by 1~2% of raw material, and magnesium addition content then can be reduced to below the 10ppm of product by 1~2% of raw material, satisfies the requirement of high-grade soft magnetism with ferric oxide fully.
The condition of above-mentioned two-step oxidation method demanganization, magnesium is:
(1) is controlled at 50~100g Fe/ liter with preceding concentration in the ferrous sulfate;
The alkali ratio that the neutralization of (2) one steps adds neutralizing agent is 0.20~0.50, and the alkali ratio is for adding volatile salt [(NH
4)
2CO
3] the total iron amount of weight/solution, volatile salt can be synthetic by bicarbonate of ammonia and ammoniacal liquor, 20~60 ℃ of normal temperature;
(3) oxidation step end acidity pH value is controlled to be 3.0~5.5;
The alkali ratio that the neutralization of (4) two steps adds neutralizing agent is 1.2~2.0; The same oxidizing temperature of temperature;
(5) second oxidation end acidity pH value is controlled to be 6.0~8.0;
(6) oxidizing temperature is controlled to be 50~90 ℃.
Filter with ordinary method, wash no SO with deionized water again
4 2-Till (use 1%BaCl
2Solution detects), throw out is dried about 100 ℃, can obtain iron oxide product in 650~750 ℃ of calcining 1~2h again.
Used bicarbonate of ammonia is agricultural grade, and ammoniacal liquor is technical grade, and water is ion exchanged water.
Embodiment 1:
In 3 liters of beakers, add 2.2 liters of deionized waters, add green vitriol 1200g while stirring, with the dense H of a small amount of chemical pure
2SO
4The regulator solution pH value is 2.0, and adds iron filings 12g, is heated to about 80 ℃, and stirs insulation 4 hours.Then add deionized water 350ml dilution and cooling, add 0.05% polyacrylamide 200ml again, stir and left standstill 2~3 hours after 2~5 minutes.Get the green copperas solution 3L of clear after the filtration, filtrate contains Fe 73g/L.Foreign matter content such as table 1 before and after purifying:
Major impurity content is (with Fe before and after the table 1 green vitriol purification of raw materials
2O
3Be benchmark)
Major impurity (%) | Fe purifies the rate of recovery (%) | |||||||
Ti | Ca | Si | Al | Pb | Mg | Mn | ||
Before the purification | 0.64 | 0.032 | 0.052 | 0.035 | 0.0023 | 0.960 | 0.857 | 96.56 |
After the purification | 0.005 | 0.002 | 0.0025 | 0.0021 | 0.001 | 0.958 | 0.854 |
Embodiment 2:
In 3 liters of beakers, add the copperas solution 1200ml after embodiment 1 purifies, stir and slowly drip the neutralizer 500ml that contains bicarbonate of ammonia 23g and strong aqua 23ml down for 25 ℃ at normal temperature, then be heated to 60 ℃, blowing air oxidation 3.5 hours, control terminal point pH value 4.5.And then oxidation limit, limit drips the neutralizer 800ml contain 100g bicarbonate of ammonia and 100ml strong aqua, oxidization time 6 hours, and terminal point pH value 6.8 stops oxidation and heating, continues to stir after 30 minutes to leave standstill 2 hours.Filter then, spend dried up being washed till and use 1%BaCl
2Solution detects no SO
4 2-Till, precipitation places 100 ℃ of bakings of baking oven 2~3 hours, moves to retort furnace again in 680 ℃ of calcining insulation 2h, makes ferric oxide 115g.Fe yield 91.9%.Sample analysis the results are shown in Table the soft magnetic ferrite ferric oxide industry standard SJ/T10383-98 YHT1 of the 2[Ministry of Electronics Industry and lists comparison together in].
Embodiment 3
In 3 liters of beakers, add the copperas solution 1200ml that embodiment 1 purifies, be heated to 60 ℃, stir and also slowly drip the neutralizer 550ml that contains bicarbonate of ammonia 30g and strong aqua 30ml, be warming up to 70 ℃, the blowing air oxidation is 3.5 hours then, control terminal point pH value 4.0.Oxidation limit in limit drips the neutralizer 750ml that contains bicarbonate of ammonia 98g and strong aqua 98ml again, and oxidization time 7 hours, terminal point pH value are 7.5.Stop oxidation and heating, left standstill 2 hours behind the stirring 30min.Filter then, spend the dried up no SO that is washed till
4 2-Till, precipitation places 100 ℃ of oven dry of baking oven 2~3 hours, moves to retort furnace again in 720 ℃ of calcining insulation 2h, obtains iron oxide product 114g, Fe yield 91.1%.Sample analysis sees Table 2.
Embodiment 4
Add the copperas solution 1200ml that embodiment 1 purifies in 3 liters of beakers, be heated to 60 ℃, stir and also slowly drip the neutralizer 550ml that contains bicarbonate of ammonia 25g and strong aqua 25ml, be warming up to 80 ℃, the blowing air oxidation is 3 hours then, terminal point pH value 3.5.Oxidation limit in limit drips the neutralizer 750ml that contains bicarbonate of ammonia 105g and strong aqua 105ml again, and oxidization time 6.5 hours, terminal point pH value are 7.5.Stop oxidation and heating, left standstill 2 hours behind the stirring 30min.Filter then, spend the dried up no SO that is washed till
4 2-Till, precipitation places 100 ℃ of oven dry of baking oven 2~3 hours, moves to retort furnace again in 750 ℃ of calcining insulation 1.5h, obtains iron oxide product 117g, Fe yield 93.6%.Sample analysis sees Table 2.
Table 2 embodiment sample analysis (%)
Fe 2O 3 | TiO 2 | SiO 2 | Al 2O 3 | CaO | Na 2O | MgO | MnO | SO 4 2- | |
Raw material (scavenging solution) | 0.0005 | 0.0025 | 0.0021 | 0.0020 | 0.0054 | 0.96 | 0.854 | ||
Embodiment 2 | 99.3 | <0.0005 | 0.0028 | 0.0024 | 0.0007 | 0.0051 | 0.0008 | 0.18 | 0.078 |
Embodiment 3 | 99.5 | <0.0005 | 0.0030 | 0.0018 | 0.0010 | 0.0048 | 0.0008 | 0.09 | 0.022 |
Embodiment 4 | 99.7 | <0.0005 | 0.0021 | 0.0024 | 0.0011 | 0.0040 | 0.0008 | 0.05 | 0.012 |
The YHT1 standard | ≥99.2 | ≤0.01 | ≤0.01 | ≤0.01 | ≤0.014 | ≤0.02 | ≤0.015 | ≤0.30 | ≤0.1 |
Claims (2)
1, a kind of method with preparing high purity iron oxide for soft magnet using titanium white by product ferrous sulphate, elder generation is with the green vitriol purification and impurity removal before separating manganese, magnesium, it is characterized in that going on foot neutralization and oxidation by two after the removal of impurities, manganese and magnesium are not stayed in the solution with the iron precipitation, washing is removed after filtration, the precipitated Z 250 that is oxidized to of iron rule makes high purity ferric oxide after the oven dry calcining after filtration;
The neutralization of two steps with the correlated condition of oxidation is:
(1) is controlled at 50g~100gFe/ liter with preceding concentration in the ferrous sulfate feed liquid;
It is 0.20~0.50 that the neutralization of (2) one steps adds neutralizing agent control alkali ratio, and the alkali ratio is the ratio of weight with the total iron weight of solution of volatile salt; 20~60 ℃ of temperature;
(3) oxidation step end acidity pH value is controlled to be 3.0~5.5;
The alkali ratio that the neutralization of (4) two steps adds neutralizing agent is 1.2~2.0; The same oxidizing temperature of temperature;
(5) second oxidation end acidity pH value is controlled to be 6.0~8.0;
(6) oxidizing temperature is controlled to be 50~90 ℃.
2. the method with preparing high purity iron oxide for soft magnet using titanium white by product ferrous sulphate as claimed in claim 1, the molysite deposition that it is characterized in that manganese, magnesium are made after separating is at 650~750 ℃ of calcining 1~2h.
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Cited By (4)
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CN100436334C (en) * | 2007-01-23 | 2008-11-26 | 东北大学 | Preparation method of high purity magnetic material nano ferric oxide |
CN104261485A (en) * | 2014-10-09 | 2015-01-07 | 中国有色集团(广西)平桂飞碟股份有限公司 | Method for treating reaction liquid of iron oxide red produced from calcium mineral salt through wet process |
CN105366729A (en) * | 2015-11-11 | 2016-03-02 | 何定 | Method for preparing ferroferric oxide from copperas through lime as neutralizer |
CN110436528A (en) * | 2019-09-23 | 2019-11-12 | 中钢集团安徽天源科技股份有限公司 | A kind of preparation method of 9 based ferrite high-purity iron oxide red |
Family Cites Families (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN1156406C (en) * | 2000-08-02 | 2004-07-07 | 湖南株洲化工集团有限责任公司 | Process of producing high-purity magnetic iron oxide with ferous sulfate as by-product of titanium white production |
CN1193937C (en) * | 2001-03-13 | 2005-03-23 | 黄致祥 | Production process of high-purity ferric oxide for ferrite |
-
2006
- 2006-03-24 CN CNB200610018642XA patent/CN100351181C/en not_active Expired - Fee Related
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN100436334C (en) * | 2007-01-23 | 2008-11-26 | 东北大学 | Preparation method of high purity magnetic material nano ferric oxide |
CN104261485A (en) * | 2014-10-09 | 2015-01-07 | 中国有色集团(广西)平桂飞碟股份有限公司 | Method for treating reaction liquid of iron oxide red produced from calcium mineral salt through wet process |
CN105366729A (en) * | 2015-11-11 | 2016-03-02 | 何定 | Method for preparing ferroferric oxide from copperas through lime as neutralizer |
CN110436528A (en) * | 2019-09-23 | 2019-11-12 | 中钢集团安徽天源科技股份有限公司 | A kind of preparation method of 9 based ferrite high-purity iron oxide red |
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