CN102060335B - Method for preparing ammonium ferrous sulfate from waste ferrous slag in sulfuric acid process titanium dioxide industry - Google Patents
Method for preparing ammonium ferrous sulfate from waste ferrous slag in sulfuric acid process titanium dioxide industry Download PDFInfo
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- CN102060335B CN102060335B CN 201010528662 CN201010528662A CN102060335B CN 102060335 B CN102060335 B CN 102060335B CN 201010528662 CN201010528662 CN 201010528662 CN 201010528662 A CN201010528662 A CN 201010528662A CN 102060335 B CN102060335 B CN 102060335B
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Abstract
The invention discloses a method for preparing ammonium ferrous sulfate from waste ferrous slag in sulfuric acid process titanium dioxide industry, and the ammonium ferrous sulfate is synthesized by causing the waste ferrous slag to react with sulfuric acid and ammonia at a weight ratio. The method comprises the following steps: pumping 2 parts by weight of dissolving solution containing 7.5-7.6wt% of the sulfuric acid into a reaction vessel, starting an agitator, adding 1 part by weight of the waste ferrous slag, and then stirring for 0.5-1.5 hours; adding the ammonia, controlling the solution temperature in the reaction vessel to be not more than 110 DEG C and the pH value to be not more than 1.0, stopping adding the ammonia when the pH value is increased to 0.5, and keeping the temperature for 0.5-1.5 hours to obtain ammonium ferrous sulfate mixed solution; and cooling, crystallizing, separating and purifying the mixed solution to obtain the solid-phase ammonium ferrous sulfate, wherein, the obtained liquid phase is utilized as recyclable mother solution after sulfuric acid/water is replenished. The method has the advantages of short process flow and less equipment investment, and is simple and convenient in operation; the waste acid and the waste ferrous slag in the sulfuric acid process titanium dioxide industry are taken as the main raw materials, thus achieving the purpose of turning waste into wealth; and the obtained product has the advantages of good market prospect and obvious comprehensive benefit.
Description
Technical field
The present invention relates to the preparation method of ferrous ammonium sulphate, be specifically related to prepare the method for ferrous ammonium sulphate with the useless ferrous slag of sulfuric acid method titanium pigment industry.
Background technology
A kind of double salt that ferrous ammonium sulphate is made up of moles such as ferrous sulfate and ammonium sulfate is commonly called as Mohr's salt, often with hexahydrate [(NH
4)
2SO
4FeSO
46H
2O] the form existence, it is reductive agent and a basic chemical industry raw material common in the analytical chemistry, is used to prepare ferrous ion standardized solution and quantitative analysis standard reagent, demarcates potassium permanganate and potassium bichromate solution; In agricultural, forestry, be used as iron fertilizer; Also Chang Zuowei Weak-acid cation promoting agent is as Biocidal algae-killing agent and polymerizing catalyst; All has vast market prospect in industries such as medicine, plating.
The traditional preparation process technology of ferrous ammonium sulphate (accompanying drawing 1): scrap iron (iron powder or iron plate) is after thermokalite oil removing impurity elimination and clear water are cleaned, drained; Produce copperas solution earlier with the dilute sulphuric acid reaction; Filtering and impurity removing, the ammonia sulfate crystal of adding and ferrous sulfate equimolar amount in filtrating, stirring and dissolving; Heating concentrates and makes high-concentration sulfuric acid ferrous ammonium mixing solutions, gets the finished product ferrous ammonium sulphate through crystallisation by cooling, separation and purification.Traditional process equipment is simple, and raw material is clear, reduced investment; Cost is transparent, and its quality depends on the control of material purity and reaction process condition, and is easy to operate; Production process only have small quantity of hydrogen, acid mist and alkaline degreasing impurity elimination waste water waste residue efflux, so this technology is used till today as classics always.
White titanium pigment be a kind of be the important white inorganic pigment of main body composition with titanium oxide; In coating, printing ink, rubber, papermaking and chemical fibre industry, be used as pigment; Be used to make welding electrode, isolator and electroceramics in mechanical industry, also have a wide range of applications in industry such as sugared porcelain, metallurgy.At present, about 8,000,000 tons/year of global white titanium pigment aggregated capacity, the China's titanium ore resources is abundant, low in raw material cost, is easy to get, and aggregated capacity surpasses 2,500,000 tons, and ultimate production has also reached 2,000,000 tons, and still with the annual growth rate fast development more than 10%.
Sulfuric acid process is the current topmost titanium white production method of China, and this method is main with periodical operation, and technology is ripe; Equipment is simple, low in raw material cost, is easy to get, but long flow path; The consumption of sulfuric acid and water is big, and spent acid, iron vitriol and useless ferrous slag the like waste are many, and environmental pollution is big.In order to reduce environmental pollution, conventional sulfuric acid has been carried out many-sided improvement, as replacing ilmenite with solubility in acid titanium slag, ilmenite concentrate, utilizing technology by-product exhaust steam that spent acid is concentrated directly concentrated decrement or the like of recovery, hydrolysising mother liquid.According to preresearch estimates, surplus the annual by-product spent acid 800 of China's titanium white powder production industry ten thousand tons, nearly 3,000,000 tons of by-product iron vitriol, about 1,000,000 tons of the ferrous slag of by-product.Spent acid can be through concentrating means digestion such as recovery and other Chemicals of direct production, and the low-concentration waste acid that does not have recovery value in a large number also can carry out harmless treatment through simple neutralization; The channel of iron vitriol comprehensive utilization is a lot, as making water purification agent, iron pigment, agricultural chemicals, catalyzer, fertilizer, the blue or green orchid of titanium and fodder additives etc.;
It is the patent of CN101792187A that Chinese patent discloses the patent No. on August 4th, 2010; With the titanium white waste acid condensed slag is raw material; The processes such as acid, crystallisation by cooling, separation, commentaries on classics crystalline substance of falling through condensed slag are produced feed grade ferrous sulfate monohydrate, have realized the comprehensive utilization of sulfuric acid method titanium pigment by product spent acid condensed slag with high cost.Ferrous slag is high, big, the thick corrodibility mud of acidity of a kind of khaki color, iron content, and its molecule constitutes FeSO
4XH
2SO
4YH
2O, x=0.5～0.6, y=0.9～1.2.It can't directly be used as iron vitriol; Big to environmental hazard; So far do not find the gratifying approach that effectively utilizes yet; Can only be as in addition harmless treatment of Hazardous wastes, though or infiltrate that pyrite-based sulfuric acid production---these means have reached the purpose of decontamination basically, the cost of paying extremely expensive (so many white titanium pigments enterprise all takes the environmental protection responsibility of means escapes oneself such as row steathily).
Summary of the invention
In order to improve the raw material mix of ferrous ammonium sulphate traditional preparation process technology, the useless ferrous slag of recycling sulfuric acid method titanium pigment industry (hereinafter to be referred as useless ferrous slag), the present invention provides the method for preparing ferrous ammonium sulphate with the useless ferrous slag of sulfuric acid method titanium pigment industry; With useless ferrous slag is main raw material, is reagent with sulfuric acid, ammonia, makes ferrous ammonium sulphate; Make a silk purse out of a sow's ear; Not only eliminated the environmental protection puzzlement of sulfuric acid method titanium pigment industry development, economized on resources, reduced cost; And started the new preparation process of ferrous ammonium sulphate, have important theoretical and be worth and realistic meaning.The present invention realizes through following technical scheme.
The method for preparing ferrous ammonium sulphate with the useless ferrous slag of sulfuric acid method titanium pigment industry; Comprise the steps: that (1) is that the lysate of 7.5～7.6wt% pumps into reactor with the sulfuric acid content of 2 parts of weight; Start stirrer; Restir behind the useless ferrous slag of 1 part of weight of adding is when temperature no longer raises, when feed liquid has been converted into the tawny clear liquid, accomplish dissolving and hydrolysis; (2) add ammonia again, the liquid temperature is no more than 110 ℃ in the control reactor, and the pH value when the pH value is elevated to 0.5, shows that the dosage of ammonia is enough below 1.0, stops ammonification immediately, continues insulation reaction 0.5～1.5h, gets the ferrous ammonium sulphate mixing solutions; (3) mixing solutions solid phase after crystallisation by cooling, separation and purification is the ferrous ammonium sulphate product, and last liquid phase is as the mother liquor that can be recycled.
The above-mentioned method for preparing ferrous ammonium sulphate with the useless ferrous slag of sulfuric acid method titanium pigment industry; Be used as lysate after in the conditioning groove, adding sulfuric acid/water behind the said mother liquor; Pump into reactor and recycle, the additional amount of sulfuric acid/water so that in the lysate sulfuric acid content be 7.5～7.6wt%.
Above-mentionedly prepare the method for ferrous ammonium sulphate with the useless ferrous slag of sulfuric acid method titanium pigment industry, the said restir time of step (1) is 0.5～1.5h.
Above-mentionedly prepare the method for ferrous ammonium sulphate with the useless ferrous slag of sulfuric acid method titanium pigment industry, said useless ferrous slag is the hydrolysis of sulfuric acid method titanium pigment industry titanyl sulfate, separate metatitanic acid after mother liquor behind enrichment process, discharge, its molecule constitutes FeSO
4XH
2SO
4YH
2O, x=0.5～0.6, y=0.9～1.2.
Above-mentionedly prepare the method for ferrous ammonium sulphate with the useless ferrous slag of sulfuric acid method titanium pigment industry, said ammonia is one or both of liquefied ammonia, ammoniacal liquor.
Above-mentionedly prepare the method for ferrous ammonium sulphate with the useless ferrous slag of sulfuric acid method titanium pigment industry, said sulfuric acid, liquefied ammonia and ammoniacal liquor are one or more of chemical reagent, industrial goods, waste material of different grades.
Compared with prior art, the present invention has following advantage:
(1) useless ferrous slag is that the sulfuric acid method titanium pigment industry is difficult to primary pollution source of effectively utilizing and the main bottleneck that restricts industry development, important prerequisite and basic guarantee that it is the sulfuric acid method titanium pigment industry development that low-cost high-efficiency is eliminated its harm to ecotope beneficially.The present invention is the new channel that useless ferrous slag has been opened up a comprehensive utilization of resources, and it is made a silk purse out of a sow's ear, and makes the best use of everything, and will significantly improve sulfuric acid method titanium pigment industry cleaner production level, and will produce remarkable economical, social benefit.
(2) the present invention has thoroughly changed the raw material mix of ferrous ammonium sulphate traditional processing technology; With useless ferrous slag is main raw material; With sulfuric acid, ammonia (liquefied ammonia or ammoniacal liquor) is reagent, replaces scrap iron (iron powder or iron plate), dilute sulphuric acid and the ammonium sulfate of traditional processing technology, makes the high-quality ferrous ammonium sulphate; Further shorten and simplified technical process, started the new preparation process of ferrous ammonium sulphate.
(3) new preparation process of the ferrous ammonium sulphate of the present invention's proposition; Not only raw material sources are recycled in the resource utilization of refuse; And do not have pollutents such as alkaline degreasing impurity elimination waste water, waste gas and waste residue to efflux, and mother liquid recycling, technology itself is more green, more environmental protection, more energy-conservation.
(4) clean process to scrap iron (iron powder or iron plate) itself, thermokalite oil removing impurity elimination and clear water in the ferrous ammonium sulphate traditional processing technology and possibly comprise impurity; The concentration and evaporation process also possibly cause defectives such as ferrous oxidation; The ferrous ammonium sulphate preparation method that the present invention adopted does not comprise fully that then these mainly cause general labourer's preface; The raw material that is adopted does not contain the detrimental impurity that influences quality of finished basically yet, so technology of the present invention more can be guaranteed the ferrous ammonium sulphate quality.
Description of drawings
Fig. 1 is the traditional preparation process process diagram of ferrous ammonium sulphate.
Fig. 2 is a technical matters general flow chart of the present invention.
Embodiment
Below to combine embodiment that enforcement of the present invention is described further.
Embodiment1
The dilute sulphuric acid that takes by weighing 500g concentration and be 7.6wt% is made lysate, pours the flat there-necked flask of 1000mL of band magnetic agitation into, under agitation condition, slowly adds the useless ferrous slag of 250g, and 30min accomplishes and dissolves and hydrolysis; Open the liquefied ammonia valve, slowly charge into ammonia, the liquid temperature is no more than 110 ℃ in the control reactor, and the pH value increases to 0.5 behind about 56min, fastens the liquefied ammonia valve, continues reaction 30min; Stirring, water-bath cooling, a large amount of light blue crystal grain are high-visible, and again with the ice-water bath cooling, the 30min post crystallization is accomplished when near room temperature; Utilize centrifugation apparatus to separate mother liquor and crystal grain, get the mother liquor about 313.4g ferrous ammonium sulphate and 460.0g.Add the 40g vitriol oil (95wt%) in the mother liquor and promptly can be used as lysate (amount to 500g) and recycle, finished product ferrous ammonium sulphate content reaches 95.76wt%, the content standard of far ultra ferrous ammonium sulphate industrial goods 90wt%.
Embodiment2
Take by weighing the lysate of 200g from embodiment 1, pour the flat there-necked flask of 500mL of band magnetic agitation into, under agitation condition, slowly add the useless ferrous slag of 100g, 70min accomplishes dissolving and hydrolysis; Then the velocity flow with 5.00mL/min adds 28wt% analytical pure ammoniacal liquor, and the liquid temperature is no more than 110 ℃ in the control reactor, and the pH value increases to 0.5 behind about 10min, and termination of pumping immediately continues reaction 30min; Through water-bath, ice-water bath cooling, utilize centrifugation apparatus to separate mother liquor and crystal grain, get the mother liquor about 149.8g ferrous ammonium sulphate and 184g.Add the 16g vitriol oil in the mother liquor and promptly can be used as lysate and recycle, the ferrous ammonium sulphate effective content of finished product reaches 93.67wt%, surpasses the content standard of ferrous ammonium sulphate industrial goods 90wt%.
Embodiment3
Operate equally with embodiment 2, just substitute 28wt% analytical pure ammoniacal liquor, finally can get the mother liquor about 153.5g ferrous ammonium sulphate and 179.5g with the 35wt% industrial ammonia.Adding 20.5g concentration in the mother liquor and be 75% sulfur waste acid can recycle as lysate, and the ferrous ammonium sulphate effective content of finished product reaches 92.31wt%, surpasses the content standard of ferrous ammonium sulphate industrial goods 90wt%.
Embodiment4
The dilute sulphuric acid that takes by weighing 500kg concentration and be 7.6wt% is made lysate, pumps into the 1000L dissolving hydrolytic tank that band stirs, and starts stirrer, slowly adds the useless ferrous slag of 250kg, finishes and continues to stir 30min; Then open the liquefied ammonia valve, with the filling of the speed about 0.5kg/min liquefied ammonia, the liquid temperature is no more than 110 ℃ in the control reactor, and the pH value increases to 0.5 behind about 61min, closes the liquefied ammonia valve, continues reaction 30min; Mixed solution is put into mold carry out crystallisation by cooling, separation and purification, get the mother liquor about 308.1kg ferrous ammonium sulphate and 460.3kg.Mother liquor enters the conditioning groove, add the 38.5kg industrial sulphuric acid (98～99wt%) with the 1.2L tap water, promptly can be used as lysate (amount to 500kg) and recycle.The ferrous ammonium sulphate content 94.89wt% of finished product is above the specification of quality of ferrous ammonium sulphate industrial goods 90wt%.
Embodiment5
500kg lysate in the embodiment 4 conditioning grooves is pumped into the 1000L dissolving hydrolytic tank that band stirs, start stirrer, slowly add the useless ferrous slag of 250kg, finish and continue to stir 80min; Then open the liquefied ammonia valve, with the filling of the speed about 0.5kg/min liquefied ammonia, the liquid temperature is no more than 110 ℃ in the control reactor, and the pH value increases to 0.5 behind about 67min, closes the liquefied ammonia valve, continues reaction 30min; Mixed solution is put into mold carry out crystallisation by cooling, separation and purification, get the mother liquor about 368.5kg ferrous ammonium sulphate and 416.7kg.Mother liquor enters the conditioning groove, adds the acid of 76kg sulfur waste (50wt%) and 7.3L tap water.The effective content 95.01wt% of finished product ferrous ammonium sulphate is above the specification of quality of ferrous ammonium sulphate industrial goods 90wt%.
Embodiment6
Operate equally with embodiment 5, just substitute liquefied ammonia with the 35wt% industrial ammonia, finally can get the ferrous sulfate ammonium product of 375.4kg content 93.22wt% and the mother liquor about 461kg, mother liquor only need be added the 39kg industrial sulphuric acid at the conditioning groove, and (98～99wt%) get final product.
Claims (4)
1. the method for preparing ferrous ammonium sulphate with the useless ferrous slag of sulfuric acid method titanium pigment industry; It is characterized in that comprising the steps: that (1) is that the lysate of 7.5～7.6wt% pumps into reactor with the sulfuric acid content of 2 parts of weight; Start stirrer; Restir behind the useless ferrous slag of 1 part of weight of adding is when temperature no longer raises, when feed liquid has been converted into the tawny clear liquid, accomplish dissolving and hydrolysis; (2) add ammonia again, the liquid temperature is no more than 110 ℃ in the control reactor, and the pH value when the pH value is elevated to 0.5, stops ammonification below 1.0 immediately, continues insulation reaction 0.5～1.5h, gets the ferrous ammonium sulphate mixing solutions; Said ammonia is one or both of liquefied ammonia, ammoniacal liquor; (3) mixing solutions solid phase after crystallisation by cooling, separation and purification is the ferrous ammonium sulphate product, and last liquid phase is as the mother liquor that can be recycled; As lysate, pump into reactor and recycle said mother liquor is added sulfuric acid/water in the conditioning groove after, sulfuric acid content is 7.5～7.6wt% in the lysate.
2. according to claim 1ly prepare the method for ferrous ammonium sulphate, it is characterized in that the said restir time of step (1) is 0.5～1.5h with the useless ferrous slag of sulfuric acid method titanium pigment industry.
3. the method for preparing ferrous ammonium sulphate with the useless ferrous slag of sulfuric acid method titanium pigment industry according to claim 1; It is characterized in that said useless ferrous slag is that mother liquor is discharged behind enrichment process behind the hydrolysis of sulfuric acid method titanium pigment industry titanyl sulfate, the separation metatitanic acid, its molecule constitutes FeSO
4XH
2SO
4YH
2O, x=0.5～0.6, y=0.9～1.2.
4. according to claim 3ly prepare the method for ferrous ammonium sulphate, it is characterized in that said sulfuric acid, liquefied ammonia and ammoniacal liquor are one or more of chemical reagent, industrial goods, waste material of different grades with the useless ferrous slag of sulfuric acid method titanium pigment industry.
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| CN102419321B (en) * | 2011-08-24 | 2013-11-13 | 同济大学 | Method for determining maximum value of ferrous ion impurity content |
| CN110586950A (en) * | 2019-10-14 | 2019-12-20 | 王敏 | Method for preparing 3D printing material by using titanium dioxide byproduct |
| CN111847520A (en) * | 2020-08-07 | 2020-10-30 | 攀枝花学院 | Preparation method of ammonium ferrous sulfate |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4058389A (en) * | 1974-12-20 | 1977-11-15 | Societa' Italiana Resine S.I.R. S.P.A. | Process for the preparation of fertilizers and soil modifiers |
| CN1200364A (en) * | 1997-05-22 | 1998-12-02 | 上海太平洋化工(集团)有限公司 | Method for preparing ferrous ammonium sulfate by using waste water from sulfuric acid method prodn. of titanium dioxide |
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| CA2527494A1 (en) * | 2003-05-27 | 2004-12-09 | Environmental Technologies Capital Partners, Llc | Organic recycling with metal addition |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4058389A (en) * | 1974-12-20 | 1977-11-15 | Societa' Italiana Resine S.I.R. S.P.A. | Process for the preparation of fertilizers and soil modifiers |
| CN1200364A (en) * | 1997-05-22 | 1998-12-02 | 上海太平洋化工(集团)有限公司 | Method for preparing ferrous ammonium sulfate by using waste water from sulfuric acid method prodn. of titanium dioxide |
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