CN113562772B - Preparation method of ferrous sulfate tetrahydrate - Google Patents
Preparation method of ferrous sulfate tetrahydrate Download PDFInfo
- Publication number
- CN113562772B CN113562772B CN202110889957.6A CN202110889957A CN113562772B CN 113562772 B CN113562772 B CN 113562772B CN 202110889957 A CN202110889957 A CN 202110889957A CN 113562772 B CN113562772 B CN 113562772B
- Authority
- CN
- China
- Prior art keywords
- ferrous sulfate
- sulfate tetrahydrate
- treatment
- temperature
- crystal transformation
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 229910000359 iron(II) sulfate Inorganic materials 0.000 title claims abstract description 102
- 239000011790 ferrous sulphate Substances 0.000 title claims abstract description 90
- 235000003891 ferrous sulphate Nutrition 0.000 title claims abstract description 90
- 238000002360 preparation method Methods 0.000 title claims abstract description 16
- BAUYGSIQEAFULO-UHFFFAOYSA-L iron(2+) sulfate (anhydrous) Chemical compound [Fe+2].[O-]S([O-])(=O)=O BAUYGSIQEAFULO-UHFFFAOYSA-L 0.000 title claims abstract 22
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims abstract description 65
- 239000013078 crystal Substances 0.000 claims abstract description 52
- GWEVSGVZZGPLCZ-UHFFFAOYSA-N titanium dioxide Inorganic materials O=[Ti]=O GWEVSGVZZGPLCZ-UHFFFAOYSA-N 0.000 claims abstract description 50
- 230000009466 transformation Effects 0.000 claims abstract description 49
- 239000012452 mother liquor Substances 0.000 claims abstract description 38
- 238000000034 method Methods 0.000 claims abstract description 37
- 229910052742 iron Inorganic materials 0.000 claims abstract description 35
- 238000000926 separation method Methods 0.000 claims abstract description 22
- 239000007791 liquid phase Substances 0.000 claims abstract description 18
- 239000007788 liquid Substances 0.000 claims abstract description 11
- 239000011259 mixed solution Substances 0.000 claims abstract description 11
- 239000002253 acid Substances 0.000 claims description 16
- 238000010438 heat treatment Methods 0.000 claims description 16
- 238000006243 chemical reaction Methods 0.000 claims description 15
- 239000000126 substance Substances 0.000 claims description 15
- 238000003756 stirring Methods 0.000 claims description 12
- 238000004519 manufacturing process Methods 0.000 claims description 10
- 239000007787 solid Substances 0.000 claims description 8
- 238000002156 mixing Methods 0.000 claims description 4
- 239000004568 cement Substances 0.000 abstract description 9
- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 abstract description 6
- 229910052804 chromium Inorganic materials 0.000 abstract description 6
- 239000011651 chromium Substances 0.000 abstract description 6
- 230000007613 environmental effect Effects 0.000 abstract description 4
- SURQXAFEQWPFPV-UHFFFAOYSA-L iron(2+) sulfate heptahydrate Chemical compound O.O.O.O.O.O.O.[Fe+2].[O-]S([O-])(=O)=O SURQXAFEQWPFPV-UHFFFAOYSA-L 0.000 description 90
- 239000000243 solution Substances 0.000 description 22
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 20
- 230000008569 process Effects 0.000 description 13
- 230000000052 comparative effect Effects 0.000 description 12
- 239000002699 waste material Substances 0.000 description 10
- 238000002425 crystallisation Methods 0.000 description 9
- 239000000047 product Substances 0.000 description 9
- 230000008025 crystallization Effects 0.000 description 8
- -1 iron ions Chemical class 0.000 description 8
- XBDUTCVQJHJTQZ-UHFFFAOYSA-L iron(2+) sulfate monohydrate Chemical compound O.[Fe+2].[O-]S([O-])(=O)=O XBDUTCVQJHJTQZ-UHFFFAOYSA-L 0.000 description 8
- 238000003825 pressing Methods 0.000 description 8
- YDZQQRWRVYGNER-UHFFFAOYSA-N iron;titanium;trihydrate Chemical compound O.O.O.[Ti].[Fe] YDZQQRWRVYGNER-UHFFFAOYSA-N 0.000 description 7
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 7
- 230000000694 effects Effects 0.000 description 5
- 239000012047 saturated solution Substances 0.000 description 5
- 235000010215 titanium dioxide Nutrition 0.000 description 5
- 239000003638 chemical reducing agent Substances 0.000 description 4
- 238000001914 filtration Methods 0.000 description 4
- 230000007062 hydrolysis Effects 0.000 description 4
- 238000006460 hydrolysis reaction Methods 0.000 description 4
- 238000002386 leaching Methods 0.000 description 4
- 239000000203 mixture Substances 0.000 description 4
- 239000007790 solid phase Substances 0.000 description 4
- CWYNVVGOOAEACU-UHFFFAOYSA-N Fe2+ Chemical compound [Fe+2] CWYNVVGOOAEACU-UHFFFAOYSA-N 0.000 description 3
- 230000008901 benefit Effects 0.000 description 3
- 238000005660 chlorination reaction Methods 0.000 description 3
- 238000005516 engineering process Methods 0.000 description 3
- 238000003860 storage Methods 0.000 description 3
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 description 2
- 238000005054 agglomeration Methods 0.000 description 2
- 230000002776 aggregation Effects 0.000 description 2
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 2
- 239000003795 chemical substances by application Substances 0.000 description 2
- JOPOVCBBYLSVDA-UHFFFAOYSA-N chromium(6+) Chemical compound [Cr+6] JOPOVCBBYLSVDA-UHFFFAOYSA-N 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 238000010899 nucleation Methods 0.000 description 2
- 229910052760 oxygen Inorganic materials 0.000 description 2
- 239000001301 oxygen Substances 0.000 description 2
- 239000002994 raw material Substances 0.000 description 2
- 230000009467 reduction Effects 0.000 description 2
- 239000010802 sludge Substances 0.000 description 2
- 235000008733 Citrus aurantifolia Nutrition 0.000 description 1
- 239000011398 Portland cement Substances 0.000 description 1
- 235000011941 Tilia x europaea Nutrition 0.000 description 1
- 238000009825 accumulation Methods 0.000 description 1
- 239000000654 additive Substances 0.000 description 1
- 230000000844 anti-bacterial effect Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 239000003153 chemical reaction reagent Substances 0.000 description 1
- ZCDOYSPFYFSLEW-UHFFFAOYSA-N chromate(2-) Chemical compound [O-][Cr]([O-])(=O)=O ZCDOYSPFYFSLEW-UHFFFAOYSA-N 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 125000004122 cyclic group Chemical group 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 230000001419 dependent effect Effects 0.000 description 1
- 239000010842 industrial wastewater Substances 0.000 description 1
- 229910052500 inorganic mineral Inorganic materials 0.000 description 1
- 150000002506 iron compounds Chemical class 0.000 description 1
- JEIPFZHSYJVQDO-UHFFFAOYSA-N iron(III) oxide Inorganic materials O=[Fe]O[Fe]=O JEIPFZHSYJVQDO-UHFFFAOYSA-N 0.000 description 1
- 239000004571 lime Substances 0.000 description 1
- 235000010755 mineral Nutrition 0.000 description 1
- 239000011707 mineral Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000006386 neutralization reaction Methods 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 239000008188 pellet Substances 0.000 description 1
- 238000005453 pelletization Methods 0.000 description 1
- 239000000843 powder Substances 0.000 description 1
- 239000002244 precipitate Substances 0.000 description 1
- 238000001556 precipitation Methods 0.000 description 1
- 238000000746 purification Methods 0.000 description 1
- 238000003908 quality control method Methods 0.000 description 1
- 238000004064 recycling Methods 0.000 description 1
- 239000004575 stone Substances 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 238000012876 topography Methods 0.000 description 1
- 229910052720 vanadium Inorganic materials 0.000 description 1
- LEONUFNNVUYDNQ-UHFFFAOYSA-N vanadium atom Chemical compound [V] LEONUFNNVUYDNQ-UHFFFAOYSA-N 0.000 description 1
- 238000004065 wastewater treatment Methods 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01G—COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSES C01D OR C01F
- C01G49/00—Compounds of iron
- C01G49/14—Sulfates
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Inorganic Chemistry (AREA)
- Inorganic Compounds Of Heavy Metals (AREA)
Abstract
The invention relates to the technical field of ferrous sulfate tetrahydrate preparation, in particular to a preparation method of ferrous sulfate tetrahydrate. The preparation method of ferrous sulfate tetrahydrate comprises the following steps: concentrating and crystal transformation are carried out on the synthetic rutile mother liquor, and then solid-liquid separation is carried out, so as to obtain ferrous sulfate tetrahydrate and a liquid phase system containing ferrous sulfate; the temperature of the concentration treatment is 60-80 ℃; the concentration treatment is carried out until the mass percentage of iron in the mixed solution is 14-18%; the temperature of the crystal transformation treatment is 60-80 ℃. The method greatly reduces the treatment cost of the synthetic rutile mother liquor, scientifically and effectively utilizes the synthetic rutile mother liquor, and simultaneously produces ferrous sulfate tetrahydrate with high added value, which is used for environmental protection, cement chromium removal and the like.
Description
Technical Field
The invention relates to the technical field of ferrous sulfate tetrahydrate preparation, in particular to a preparation method of ferrous sulfate tetrahydrate.
Background
The titanium white by the chlorination method has the advantages of short production flow, easily enlarged production capacity, high continuous automation degree, stable product quality control compared with the sulfuric acid method, less three wastes and less environmental protection problem, and becomes the main stream production technology of titanium white. With the gradual expansion of the productivity of the chlorination process, the demand for raw materials is also gradually increasing. At present, the preparation methods of the synthetic rutile are numerous, but the technological process is complex, and the main methods capable of realizing industrialization at present are a reduction rust method and an acid leaching method. The hydrochloric acid leaching method can obtain high-grade synthetic rutile, but the granularity of the product is too fine, and meanwhile, the secondary flow is long, the production cost is high, and the equipment corrosion is serious in the production process, so that the industrial application of the process is limited. With the continuous development of the technology for preparing the synthetic rutile, the method for preparing the synthetic rutile by adopting the titanium white waste acid to leach and reduce ilmenite has the advantages of low cost, good quality, high yield and low equipment requirement, but the problem that the separated synthetic rutile mother liquor is difficult to treat exists, and if the obtained synthetic rutile mother liquor cannot be reasonably treated or utilized, the development of the method is directly restricted.
The method is characterized in that the synthetic rutile mother liquor ferrous sulfate solution separated from the synthetic rutile prepared by leaching and reducing ilmenite with titanium white waste acid is saturated solution, the crystallization rate is only about 30% by direct vacuum cooling crystallization, and the residual solution needs further treatment; and the solution contains about 3 percent of sulfuric acid, so that a large amount of iron ions consume a large amount of stone powder or carbide sludge to generate a large amount of yellow sludge, which is difficult to use and causes resource waste.
Ferrous sulfate tetrahydrate is different from ferrous sulfate monohydrate (Huang Yatie) and ferrous sulfate heptahydrate (green vanadium), the appearance of the product is light green or light yellow green crystalline solid, the pH value of alkaline water can be adjusted by adding a certain amount, the product is organically combined with suspended matters in water, and the precipitation is accelerated, so that the product is mainly applied to water quality purification and industrial wastewater treatment, and meanwhile, the product has a bactericidal effect; can also be used as hexavalent chromium reducing agent in cement. Although copperas and ferrous yellow can also be used as reducing agents for hexavalent chromium in cement manufacture. Both materials have drawbacks. The disadvantage of copperas is that the material is difficult to store and handle, it tends to agglomerate during storage, and therefore problems are encountered in the storage tank blanking, and poor flow characteristics also make the addition process more difficult. In addition, the copperas may precipitate out attached water, which then may collect at the bottom of the copperas storage tank and cause problems. In this wet state, copperas are easily oxidized by oxygen in the air, and thus the reduction effect is greatly reduced. Oxidation of copperas occurs more readily at higher temperatures. The solubility of copperas is also strongly dependent on temperature. Starting at about 40 ℃, copperas dissolve in its own crystal water and are then easily oxidized by the oxygen in the air, losing their role as chromate reducer.
On the other hand, ferrous sulfate monohydrate has the disadvantage of having a large amount of attached sulfuric acid, usually 20% or more. Whereas ordinary portland cement is alkaline, the sulfuric acid reacts with the cement clinker and thus produces large agglomerates. Thus, ferrous yellow must be neutralized with mineral additives such as lime or treated with metallic iron and basic iron compounds to form additional ferrous sulfate mixtures. The same applies to mixtures of copperas and ferrous yellow. To improve the flowability of the neutralized ferrous sulfate, it may be granulated. However, the disadvantage of pelletization is that ferrous sulfate loses its reducing power if the pellets become too hard. Since ferrous sulfate monohydrate (Huang Yatie) is less soluble in water than ferrous sulfate heptahydrate (copperas), the solubility can be increased by adding water to ferrous sulfate peryellow. But even so, sulfuric acid attached to the ferrous sulfate monohydrate (Huang Yatie) must be neutralized.
In view of this, the present invention has been made.
Disclosure of Invention
The invention aims to provide a preparation method of ferrous sulfate tetrahydrate, which is characterized in that synthetic rutile mother liquor is concentrated and subjected to crystal transformation, and ferrous sulfate tetrahydrate is obtained by controlling the concentration temperature and the content of iron ions in the solution and the crystal transformation temperature; the method greatly reduces the treatment cost of the synthetic rutile mother liquor, scientifically and effectively utilizes the synthetic rutile mother liquor, and simultaneously produces ferrous sulfate tetrahydrate with high added value, which is used for environmental protection, cement chromium removal and the like.
In order to achieve the above object of the present invention, the following technical solutions are specifically adopted:
the preparation method of ferrous sulfate tetrahydrate comprises the following steps:
concentrating and crystal transformation are carried out on the synthetic rutile mother liquor, and then solid-liquid separation is carried out, so as to obtain ferrous sulfate tetrahydrate and a liquid phase system containing ferrous sulfate;
the temperature of the concentration treatment is 60-80 ℃; the concentration treatment is carried out until the mass percentage of iron in the mixed solution is 14-18%;
the temperature of the crystal transformation treatment is 60-80 ℃.
Preferably, the synthetic rutile mother liquor is subjected to pretreatment, and the pretreatment comprises the following steps:
mixing and reacting an iron simple substance and/or a substance containing the iron simple substance with the synthetic rutile mother liquor until the mass percentage of acid in a mixed system after the reaction is less than 0.1%, then carrying out solid-liquid separation, and collecting liquid for concentration treatment;
preferably, the mass percentage of the acid in the mixed system after the reaction is 0.03-0.95%.
Preferably, the temperature of the reaction is 15-90 ℃;
preferably, the temperature of the reaction is 45-70 ℃.
Preferably, the time of the crystal transformation treatment is 2-4 hours;
preferably, the time of the crystal transformation treatment is 2.5-3.5 h.
Preferably, stirring is performed during the crystal transformation treatment;
preferably, the stirring speed is 100-300 rpm.
Preferably, the temperature of the concentration treatment is 70-80 ℃;
preferably, the concentration treatment is carried out until the mass percentage of iron in the mixed solution is 15.5-17%.
Preferably, the temperature of the crystal transformation treatment is 70-75 ℃.
Preferably, the liquid phase system containing ferrous sulfate is subjected to heat treatment and then subjected to liquid-solid separation, and the liquid phase after the liquid-solid separation is subjected to concentration treatment and crystal transformation treatment.
Preferably, the temperature of the heat treatment is 90 to 95 ℃.
Preferably, the ferrous sulfate solution obtained after the separation is subjected to concentration treatment and crystal transformation treatment.
Preferably, the concentrating treatment apparatus comprises at least one of a double effect evaporator, a multiple effect evaporator and a MVR evaporator.
Compared with the prior art, the invention has the beneficial effects that:
(1) The invention provides a brand new mother liquor recycling mode for ferrous sulfate solution separated after the ilmenite is leached and reduced by waste sulfuric acid to prepare the artificial rutile, has simple process and relatively low operation cost, and obtains the ferrous sulfate tetrahydrate with high added value, so that the mother liquor of the artificial rutile is effectively and reasonably utilized, the development of the technology for preparing the artificial rutile by leaching and reducing ilmenite by titanium white waste acid can be promoted, and the environment protection guarantee is provided for the high-quality artificial rutile raw material provided by a chlorination method by the process expansion production.
(2) The invention improves the utilization value of the synthetic rutile mother liquor to the maximum extent, obtains ferrous sulfate tetrahydrate, effectively avoids secondary pollution caused by solid matter accumulation brought by the traditional treatment method or high treatment cost of the synthetic rutile mother liquor concentration crystallization method, realizes diversified utilization, comprehensive utilization and cyclic utilization of waste, has good economic benefit, and changes the traditional waste rough treatment mode.
(3) The ferrous sulfate tetrahydrate prepared by the invention is granular, is easy to disperse and not agglomerated, and has better development prospect when being used as a cement chromium removing agent, and compared with ferrous sulfate heptahydrate, the ferrous sulfate tetrahydrate is convenient to transport, store and the like.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings that are needed in the description of the embodiments or the prior art will be briefly described, and it is obvious that the drawings in the description below are some embodiments of the present invention, and other drawings can be obtained according to the drawings without inventive effort for a person skilled in the art.
FIG. 1 is a process flow diagram of the preparation of ferrous sulfate tetrahydrate in accordance with the present invention;
fig. 2 is a topography of the prepared ferrous sulfate under different conditions.
Detailed Description
Embodiments of the present invention will be described in detail below with reference to examples, but it will be understood by those skilled in the art that the following examples are only for illustrating the present invention and should not be construed as limiting the scope of the present invention. The specific conditions are not noted in the examples and are carried out according to conventional conditions or conditions recommended by the manufacturer. The reagents or apparatus used were conventional products commercially available without the manufacturer's attention.
According to one aspect of the invention, the invention relates to a method for preparing ferrous sulfate tetrahydrate, comprising the following steps:
concentrating and crystal transformation are carried out on the synthetic rutile mother liquor, and then solid-liquid separation is carried out, so as to obtain ferrous sulfate tetrahydrate and a liquid phase system containing ferrous sulfate;
the temperature of the concentration treatment is 60-80 ℃; the concentration treatment is carried out until the mass percentage of iron in the mixed solution is 14-18%;
the temperature of the crystal transformation treatment is 60-80 ℃.
In order to avoid the conditions of resource waste and high treatment cost caused by direct crystallization and neutralization and secondary pollution, the invention prepares ferrous sulfate tetrahydrate with higher added value for environmental protection, cement chromium removal and the like by simply concentrating and carrying out low-temperature crystal transformation according to the defects of copperas, huang Yatie and the mixture of copperas and ferrous sulfate described by the reducing agent for the cement chromium removal agent.
The synthetic rutile mother liquor of the invention can also be replaced by other waste liquid containing ferrous sulfate.
The temperature of the concentration treatment is controlled to be 60-80 ℃, and the obtained ferrous sulfate tetrahydrate has higher purity and higher quality. If the temperature of the concentration process is too high, ferrous sulfate monohydrate is produced, if the temperature of the concentration process is too low, the concentration efficiency is low, and if too low, ferrous sulfate heptahydrate is produced.
In one embodiment, the concentration treatment may be performed at a temperature of 60 to 80 ℃, and 60 ℃, 61 ℃, 62 ℃, 63 ℃, 64 ℃, 65 ℃, 66 ℃, 67 ℃, 68 ℃, 69 ℃, 70 ℃, 71 ℃, 72 ℃, 73 ℃, 74 ℃, 75 ℃, 76 ℃, 77 ℃, 78 ℃, 79 ℃, or 80 ℃ may be selected.
The invention comprehensively considers the yield and the purity, controls the mass percentage content of iron in the mixed solution after the concentration treatment to be 14-18%, and can obtain the ferrous sulfate tetrahydrate with high yield and high purity in the range. If the mass percentage of iron in the mixed solution after the concentration treatment is lower than 14%, the yield of ferrous sulfate tetrahydrate is low. If the mass percentage of iron in the mixed solution after the concentration treatment is more than 18%, ferrous sulfate monohydrate can be generated, and the purity of the obtained ferrous sulfate tetrahydrate is reduced.
In one embodiment, the concentration treatment is performed until the mass percentage of iron in the mixed solution is 14% -18%, and 14%, 14.5%, 15%, 16%, 16.5%, 17%, 17.5% or 18% may be selected.
The temperature of the crystal transformation process is controlled to be 60-80 ℃, and ferrous sulfate monohydrate is generated if the temperature is too high; if the temperature is too low, ferrous sulfate heptahydrate is produced.
In one embodiment, the temperature of the crystal transformation treatment is 60 to 80 ℃, and 60 ℃, 61 ℃, 62 ℃, 63 ℃, 64 ℃, 65 ℃, 66 ℃, 67 ℃, 68 ℃, 69 ℃, 70 ℃, 71 ℃, 72 ℃, 73 ℃, 74 ℃, 75 ℃, 76 ℃, 77 ℃, 78 ℃, 79 ℃, or 80 ℃ can be selected.
Preferably, the synthetic rutile mother liquor is subjected to pretreatment, and the pretreatment comprises the following steps:
mixing and reacting the iron simple substance and/or the substance containing the iron simple substance with the synthetic rutile mother liquor until the mass percentage of acid in the mixed system after the reaction is less than 0.1%, then carrying out solid-liquid separation, and collecting liquid for concentration treatment.
The substances containing the iron simple substance comprise iron powder, reduced ilmenite, other substances containing metallic iron and the like.
The mass percentage content (less than 0.1%) of acid in the synthetic rutile mother liquor is reduced by mixing the iron simple substance and/or the substance containing the iron simple substance with the synthetic rutile mother liquor, so that the utilization value of the obtained ferrous sulfate tetrahydrate can be improved, and the ferrous sulfate tetrahydrate can be better applied to cement chromium removal.
In one embodiment, the mass percent of acid in the mixed system after the reaction is 0.01%, 0.02%, 0.03%, 0.04%, 0.05%, 0.06%, 0.07%, 0.08%, 0.09%, or 0.095%.
Preferably, the mass percentage of the acid in the mixed system after the reaction is 0.03-0.95%.
Preferably, the temperature of the reaction is 15 to 90 ℃.
In one embodiment, the temperature of the reaction is 15 to 90 ℃, and 20 ℃, 25 ℃, 30 ℃, 35 ℃, 40 ℃, 45 ℃, 50 ℃, 55 ℃, 60 ℃, 65 ℃, 70 ℃, 75 ℃, 80 ℃, 85 ℃, or 90 ℃ can also be selected.
Preferably, the temperature of the reaction is 45-70 ℃.
Preferably, the time of the crystal transformation treatment is 2-4 hours.
In one embodiment, the time of the crystal transformation treatment is 2-4 h, and 2h, 2.1h, 2.2h, 2.3h, 2.4h, 2.5h, 2.6h, 2.7h, 2.8h, 2.9h, 3h, 3.1h, 3.2h, 3.3h, 3.4h, 3.5h, 3.6h, 3.7h, 3.8h, 3.9h or 4h may be selected.
Preferably, the time of the crystal transformation treatment is 2.5-3.5 h.
Preferably, stirring is performed during the crystal transformation process.
Preferably, the stirring speed is 100-300 rpm.
The invention stirs under the condition of 100-300 rpm, can accelerate crystal transformation, and simultaneously obtains high-quality ferrous sulfate tetrahydrate.
In one embodiment, the rotational speed of the stirring is 100 to 300rpm, and 110rpm, 120rpm, 130rpm, 140rpm, 150rpm, 160rpm, 170rpm, 180rpm, 190rpm, 200rpm, 210rpm, 220rpm, 230rpm, 240rpm, 250rpm, 260rpm, 270rpm, 280rpm, 290rpm or 300rpm may be selected.
Preferably, the temperature of the concentration treatment is 70-80 ℃.
Preferably, the concentration treatment is carried out until the mass percentage of iron in the mixed solution is 15.5-17%.
Preferably, the temperature of the crystal transformation treatment is 70-75 ℃.
Preferably, the liquid phase system containing ferrous sulfate is subjected to heat treatment and then subjected to liquid-solid separation, and the liquid phase after the liquid-solid separation is subjected to concentration treatment and crystal transformation treatment.
The meta-titanic acid is obtained after the heat treatment. Concentrating and crystallizing the separated mixed solution again.
Preferably, the temperature of the heat treatment is 90 to 95 ℃.
In one embodiment, the temperature of the heat treatment is 90 to 95 ℃, and 90 ℃, 91 ℃, 92 ℃, 93 ℃, 94 ℃ or 95 ℃ can be selected.
Preferably, the ferrous sulfate solution obtained after the separation is subjected to concentration treatment and crystal transformation treatment.
The mixture after the crystal transformation treatment is ferrous sulfate tetrahydrate and ferrous sulfate solution, and the ferrous sulfate solution is concentrated again.
Preferably, the concentrating treatment apparatus comprises at least one of a double effect evaporator, a multiple effect evaporator and a MVR evaporator.
The concentration equipment adopted in the concentration treatment process can be a double-effect evaporator, a multiple-effect evaporator or an MVR evaporator.
The present invention will be further explained below with reference to specific examples and comparative examples.
The process flow diagram of the ferrous sulfate tetrahydrate prepared in the embodiment of the invention is shown in figure 1.
The indexes of the artificial rutile mother liquor used in the examples and comparative examples of the present invention are shown in the following table 1.
TABLE 1 Artificial rutile mother liquor index
Example 1
The preparation method of ferrous sulfate tetrahydrate comprises the following steps:
adding iron powder into the synthetic rutile mother liquor at 25 ℃, reacting until the sulfuric acid content in the synthetic rutile mother liquor is reduced to 0.1%, settling, and filtering to obtain a low-acidity ferrous sulfate saturated solution; concentrating at 60deg.C, crystallizing until the iron ion content in the solution is 14%, maintaining the crystallization temperature at 60deg.C, stirring at 150rpm, centrifuging after 3 hr crystallization to obtain ferrous sulfate tetrahydrate with iron content of 24.65%, and other indexes and primary crystallization yields shown in Table 2 below; and (3) carrying out heating hydrolysis on the liquid phase system after centrifugal separation to obtain solid-phase metatitanic acid, wherein the heating temperature is 90 ℃, carrying out filter pressing, and returning the liquid phase obtained after filter pressing to concentration treatment.
Example 2
The preparation method of ferrous sulfate tetrahydrate comprises the following steps:
adding reduced ilmenite into the synthetic rutile mother liquor at 50 ℃, reacting until the sulfuric acid content in the synthetic rutile mother liquor is reduced to 0.08%, settling, and filtering to obtain a low-acidity ferrous sulfate saturated solution; concentrating the saturated ferrous sulfate solution at 80 ℃ until the iron ion content in the solution is 18%, carrying out crystal transformation, keeping the crystal transformation temperature at 70 ℃, stirring at 200rpm, carrying out centrifugal separation after 4h of crystal transformation to obtain ferrous sulfate tetrahydrate with the iron content of 25.74%, wherein other indexes and primary crystal transformation yield are shown in the following table 2; and (3) carrying out heating hydrolysis on the liquid phase system after centrifugal separation to obtain solid-phase metatitanic acid, wherein the heating temperature is 93 ℃, carrying out filter pressing, and returning the liquid phase obtained after filter pressing to carry out concentration treatment.
Example 3
The preparation method of ferrous sulfate tetrahydrate comprises the following steps:
adding iron powder into the synthetic rutile mother liquor at 80 ℃ for reaction until the sulfuric acid content in the synthetic rutile mother liquor is reduced to 0.05%, and then settling and filtering to obtain a low-acidity ferrous sulfate saturated solution; concentrating the saturated ferrous sulfate solution at 75 ℃, carrying out crystal transformation after the iron ion content in the solution is 16%, keeping the crystal transformation temperature at 70 ℃, stirring at 300rpm, carrying out centrifugal separation after 2h of crystal transformation to obtain ferrous sulfate tetrahydrate with the iron content of 24.87%, wherein other indexes and primary crystal transformation yield are shown in the following table 2; and (3) carrying out heating hydrolysis on the liquid phase system after centrifugal separation to obtain solid-phase metatitanic acid, wherein the heating temperature is 95 ℃, carrying out filter pressing, and returning the liquid phase obtained after filter pressing to carry out concentration treatment.
Example 4
The preparation method of ferrous sulfate tetrahydrate comprises the following steps:
adding reduced ilmenite into the synthetic rutile mother liquor at 55 ℃, reacting until the sulfuric acid content in the synthetic rutile mother liquor is reduced to 0.075%, settling, and filtering to obtain a low-acidity ferrous sulfate saturated solution; concentrating the saturated ferrous sulfate solution at 70 ℃ until the iron ion content in the solution is 17%, carrying out crystal transformation, keeping the crystal transformation temperature at 65 ℃, stirring at 250rpm, carrying out crystal transformation for 2.5h, and carrying out centrifugal separation to obtain ferrous sulfate tetrahydrate with the iron content of 25.45%, wherein other indexes and primary crystal transformation yield are shown in the following table 2; and (3) carrying out heating hydrolysis on the liquid phase system after centrifugal separation to obtain solid-phase metatitanic acid, wherein the heating temperature is 93 ℃, carrying out filter pressing, and returning the liquid phase obtained after filter pressing to carry out concentration treatment.
Comparative example 1
Except for the concentration of the saturated ferrous sulfate solution at 90 ℃, the conditions were the same as in example 4, and the obtained ferrous sulfate index and yield are shown in the following table 3.
Comparative example 2
The crystallization was performed after the iron ion content in the solution was 12%, and the obtained ferrous sulfate was subjected to the same conditions as in example 4, with the following index and yield shown in Table 3.
Comparative example 3
The crystallization was performed after the iron ion content in the solution was 20%, and the obtained ferrous sulfate was subjected to the same conditions as in example 4, as shown in Table 3 below.
Comparative example 4
The following table 3 shows the ferrous sulfate index and yield obtained in example 4, except that the seeding temperature was kept at 40 ℃.
Comparative example 5
The following table 3 shows the ferrous sulfate index and yield obtained in example 4, except that the seeding temperature was kept at 90 ℃.
Experimental example
The index of the ferrous sulfate obtained in the examples of the present invention is shown in table 2 below; the index of the ferrous sulfate obtained in the comparative example of the present invention is shown in the following table 3.
Table 2 index of ferrous sulfate obtained in examples
Table 3 index of ferrous sulfate obtained in comparative example
As can be seen from Table 2, the method of the present invention effectively utilizes the synthetic rutile mother liquor to produce ferrous sulfate tetrahydrate with high added value. Further, as shown in fig. 2 (a), the morphology of the ferrous sulfate tetrahydrate obtained in example 4 was shown, and it was found that the ferrous sulfate tetrahydrate obtained by the method of the present invention was granular, easy to disperse, and did not agglomerate; FIG. 2 (b) shows the morphology of the product obtained in comparative example 4, and the agglomeration is serious; in FIG. 2, (c) shows the morphology of the product obtained in comparative example 5, and agglomeration phenomenon occurred.
As can be seen from the comparative example, the concentration of iron in the concentrated synthetic rutile mother liquor is low, and the primary crystal transformation yield is low; the concentration temperature is high, the crystal transformation temperature is high, the iron concentration in the concentrated synthetic rutile mother liquor is high, ferrous sulfate after crystal transformation is formed by ferrous sulfate monohydrate, so that crystals turn yellow, the granularity is fine, and hardening is easy to occur; the crystal transformation temperature is low, and the crystal is mainly separated out in the form of ferrous sulfate heptahydrate.
Finally, it should be noted that: the above embodiments are only for illustrating the technical solution of the present invention, and not for limiting the same; although the invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical scheme described in the foregoing embodiments can be modified or some or all of the technical features thereof can be replaced by equivalents; such modifications and substitutions do not depart from the spirit of the invention.
Claims (12)
1. The preparation method of ferrous sulfate tetrahydrate is characterized by comprising the following steps:
concentrating and crystal transformation are carried out on the synthetic rutile mother liquor, and then solid-liquid separation is carried out, so as to obtain ferrous sulfate tetrahydrate and a liquid phase system containing ferrous sulfate;
the temperature of the concentration treatment is 60-80 ℃; the concentration treatment is carried out until the mass percentage of iron in the mixed solution is 16% -18%;
the temperature of the crystal transformation treatment is 69-79 ℃;
the synthetic rutile mother liquor is subjected to pretreatment, and the pretreatment comprises the following steps:
mixing and reacting the iron simple substance and/or the substance containing the iron simple substance with the synthetic rutile mother liquor until the mass percentage of acid in the mixed system after the reaction is less than 0.1%, then carrying out solid-liquid separation, and collecting liquid for concentration treatment.
2. The method for preparing ferrous sulfate tetrahydrate according to claim 1, wherein the mass percentage of acid in the mixed system after the reaction is 0.03% -0.95%.
3. The method for preparing ferrous sulfate tetrahydrate according to claim 2, wherein the reaction temperature is 15-90 ℃.
4. The method for preparing ferrous sulfate tetrahydrate according to claim 3, wherein the reaction temperature is 45-70 ℃.
5. The method for preparing ferrous sulfate tetrahydrate according to claim 1, wherein the time of the crystal transformation treatment is 2-4 hours.
6. The method for preparing ferrous sulfate tetrahydrate according to claim 1, wherein the time of the crystal transformation treatment is 2.5-3.5 h.
7. The method for producing ferrous sulfate tetrahydrate according to claim 1, wherein stirring is performed during the crystal transformation treatment;
the stirring speed is 100-300 rpm.
8. The method for preparing ferrous sulfate tetrahydrate according to claim 1, wherein the concentration treatment temperature is 70-80 ℃.
9. The method for preparing ferrous sulfate tetrahydrate according to claim 1, wherein the temperature of the crystal transformation treatment is 70-75 ℃.
10. The method for producing ferrous sulfate tetrahydrate according to any one of claims 1 to 9, wherein the liquid phase system containing ferrous sulfate is subjected to heat treatment and then subjected to liquid-solid separation, and the liquid phase after the liquid-solid separation is subjected to concentration treatment and crystal transformation treatment.
11. The method for preparing ferrous sulfate tetrahydrate according to claim 10, wherein the temperature of the heat treatment is 90-95 ℃.
12. The method for producing ferrous sulfate tetrahydrate according to any one of claims 1 to 9, wherein the concentrating equipment includes at least one of a multi-effect evaporator and an MVR evaporator.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110889957.6A CN113562772B (en) | 2021-08-04 | 2021-08-04 | Preparation method of ferrous sulfate tetrahydrate |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110889957.6A CN113562772B (en) | 2021-08-04 | 2021-08-04 | Preparation method of ferrous sulfate tetrahydrate |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN113562772A CN113562772A (en) | 2021-10-29 |
| CN113562772B true CN113562772B (en) | 2023-10-24 |
Family
ID=78170282
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110889957.6A Active CN113562772B (en) | 2021-08-04 | 2021-08-04 | Preparation method of ferrous sulfate tetrahydrate |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113562772B (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114162861B (en) * | 2021-12-30 | 2024-03-08 | 龙佰集团股份有限公司 | Synthetic rutile mother liquor comprehensive utilization method |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101792187A (en) * | 2009-12-30 | 2010-08-04 | 四川龙蟒钛业股份有限公司 | Method for producing feed grade ferrous sulfate monohydrate from titanium pigment waste acid condensed slag |
| CN108840373A (en) * | 2018-09-05 | 2018-11-20 | 襄阳龙蟒钛业有限公司 | A kind of method that titanium pigment waste acid recycles |
| CN110540246A (en) * | 2019-08-16 | 2019-12-06 | 中国有色集团（广西）平桂飞碟股份有限公司 | Method for preparing high-purity ferrous sulfate heptahydrate from sulfuric acid method titanium dioxide wastewater |
-
2021
- 2021-08-04 CN CN202110889957.6A patent/CN113562772B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101792187A (en) * | 2009-12-30 | 2010-08-04 | 四川龙蟒钛业股份有限公司 | Method for producing feed grade ferrous sulfate monohydrate from titanium pigment waste acid condensed slag |
| CN108840373A (en) * | 2018-09-05 | 2018-11-20 | 襄阳龙蟒钛业有限公司 | A kind of method that titanium pigment waste acid recycles |
| CN110540246A (en) * | 2019-08-16 | 2019-12-06 | 中国有色集团（广西）平桂飞碟股份有限公司 | Method for preparing high-purity ferrous sulfate heptahydrate from sulfuric acid method titanium dioxide wastewater |
Non-Patent Citations (1)
| Title |
|---|
| 何地平等编.实验22 硫酸亚铁铵的制备.《无机化学实验手册》.陕西师范大学出版社,2018,第129页. * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN113562772A (en) | 2021-10-29 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN108557877B (en) | Coproduction process of titanium white, iron oxide red and polymeric ferrous sulfate chloride | |
| CN101235440A (en) | Method of comprehensively utilizing serpentine | |
| CN101367546B (en) | Method for preparing titanium liquid and method for preparing titanium dioxide | |
| CN111634952B (en) | Method for preparing iron oxide red by using ferrous sulfate as byproduct of titanium dioxide, product and application | |
| CN1415665A (en) | Method for producing the red pigment of ferric oxide from ferrous sulphate of byproduct abolished by titanium white | |
| CN113562772B (en) | Preparation method of ferrous sulfate tetrahydrate | |
| CN111705226B (en) | Method for removing impurities from high-titanium slag | |
| CN104528834A (en) | Novel method for recycling synthetic rutile mother liquor | |
| CN104762474A (en) | Method for preparing ammonium molybdate through molybdenite | |
| CN114368781B (en) | Method for effectively recycling titanium in titanium-containing slag and improving value of byproducts | |
| CN1386710A (en) | Process for preparing superfine iron oxide | |
| CN113912130B (en) | Iron oxide red and preparation method thereof | |
| CN104291362A (en) | Method for producing potassium carbonate by using solid wastes containing potassium and chlorine ions | |
| US6696029B1 (en) | Method for the purification of zinc oxide controlling particle size | |
| CN1163415C (en) | High-purity iron oxide red producing process with iron ore powder and other iron-bearing material | |
| CN101358301A (en) | Method for directly extracting vanadium from vanadium titan magnetite concentrate | |
| CN114592120B (en) | Comprehensive utilization method for steel slag resource | |
| CN1446752A (en) | Method for preparing polymeric ferric sulfate by using partial oxidation process | |
| CN101880772A (en) | Method for recycling magnesium from magnesium-containing waste solution | |
| CN115505740A (en) | Resource method for treating red mud by adopting nitrate wastewater | |
| US4275041A (en) | Process for manufacturing a stable titanyl sulfate solution | |
| CN113772707A (en) | Treatment method of fluorine-containing potassium chloride | |
| CN101880771A (en) | Method for recovering magnesium from magnesium-contained waste liquid | |
| CN110407241A (en) | A kind of preparation method of highly active calcium oxide | |
| CN113699379B (en) | Method for recycling copper, tellurium and arsenic from black copper mud for harmless treatment |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |