CN113479938A - Method for preparing high-purity iron oxide by using iron oxide - Google Patents
Method for preparing high-purity iron oxide by using iron oxide Download PDFInfo
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- CN113479938A CN113479938A CN202110752992.3A CN202110752992A CN113479938A CN 113479938 A CN113479938 A CN 113479938A CN 202110752992 A CN202110752992 A CN 202110752992A CN 113479938 A CN113479938 A CN 113479938A
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- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01G—COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSES C01D OR C01F
- C01G49/00—Compounds of iron
- C01G49/02—Oxides; Hydroxides
- C01G49/06—Ferric oxide (Fe2O3)
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- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2006/00—Physical properties of inorganic compounds
- C01P2006/80—Compositional purity
Abstract
The invention discloses a method for preparing high-purity ferric oxide by using iron oxide. The iron element in the raw material can be greatly enriched by converting the iron oxide into the sodium ferrite, the purity of the obtained iron oxide product is higher than 99.9 percent, the quality is stable, the performance is high, and the source of the raw material for preparing the high-purity iron oxide is greatly expanded.
Description
Technical Field
The invention relates to the field of preparation of high-purity iron oxide, and in particular relates to a method for preparing high-purity iron oxide by using iron oxide.
Background
Iron oxide and oxides of other metal elements can be made into magnetic materials with different crystal structures under different conditions, such as soft magnetic ferrite, permanent magnetic ferrite, gyromagnetic ferrite and piezomagnetic ferrite, which are one of the important raw materials of the magnetic materials. The high-purity ferrite is mainly used for preparing components of products such as electronics, automobiles, household appliances, medical treatment, electric toys and the like, so the purity of the high-purity iron oxide directly determines the performance and the price of the high-purity ferrite. For example, high-quality microwave ferrite materials made of high-purity iron oxide can be used for military radars to improve the performance of the radars and play an important role in the development of electrons.
Patent CN102390869 provides a method for preparing high-purity iron oxide from alumina red mud, the method utilizes waste-alumina red mud to prepare high-purity iron oxide, iron and aluminum in the red mud are enriched in the process of enriching rare earth elements in the process of extracting the rare earth elements from the alumina red mud, and the iron and aluminum are recycled to prepare the high-purity iron oxide, and the patent does not mention the purity of the high-purity iron oxide. Patent CN107572596 discloses a method for preparing high-purity iron oxide red from high-phosphorus oolitic hematite. The high-purity iron oxide red is obtained by mixing the high-phosphorus oolitic hematite and the coal powder, and the high-purity iron oxide red is prepared by taking the high-phosphorus oolitic hematite which is difficult to utilize as a raw material, so that waste is changed into valuable; meanwhile, the problem that the utilization is influenced due to the overhigh phosphorus content in the high-phosphorus oolitic hematite is solved. Patent CN1683251 discloses a method for preparing iron oxide powder, which uses steel rolling acid washing iron mud as a base material, not only can omit the crushing procedure, but also can prepare iron sesquioxide with purity of more than 99.7% only by chemical and physical methods, and the method can greatly reduce the cost, but the hydrogen fluoride gas used in the silicon removing process can not only remove silicon, but also consume a large amount of iron in the material, so the method can obtain high-purity iron sesquioxide, but the yield of iron is lower. The patent CN102139927 provides a high-purity iron oxide black pigment and a production method thereof, the method adopts a production process of a liquid phase method, takes high-purity iron hydroxide seed crystals as carriers, adopts ferrous sulfate and sodium hydroxide to react in an oxidation barrel, immediately generates ferrous hydroxide sol under an alkaline condition, introduces steam to heat up for reaction, after reaching a specified temperature, introduces air to oxidize, and after reacting for a certain time, the required high-purity iron oxide black can be prepared. The granularity of the product obtained by the method is smaller and more uniform than that of the product obtained by the synthesis method, and the product has high yield and good color light; meanwhile, the purity of the product is controlled, and the industrial use requirement is met. The high-purity iron oxide black pigment with ferroferric oxide as the component can be prepared by the method.
With the rapid development of the information industry, the demand of ferrite is increasing day by day, and most of high-purity iron oxide in China needs to be imported, so that how to produce the iron oxide with stable quality and high performance is a problem to be solved urgently.
Disclosure of Invention
Aiming at the defects in the prior art, the invention provides a preparation method for obtaining a high-purity iron oxide product by taking iron oxide as a raw material and carrying out preparation procedures of reaction with carbonate, purification, roasting and the like, wherein the purity of the obtained iron oxide can reach more than 99.9%.
In order to overcome and solve the defects and shortcomings in the prior art, the invention adopts the following scheme:
a method for preparing high-purity iron oxide by using iron oxide comprises the following steps:
(1) uniformly mixing iron oxide and carbonate, putting the mixture into a muffle furnace for heating, heating to 1200 ℃, preserving heat for 1-1.5 hours, and cooling to obtain sodium ferrite;
(2) dissolving sodium ferrite with an acid solution to obtain an unpurified iron salt solution, adjusting the pH value of the solution to be between 0 and 2.5, and extracting, washing and back-extracting the unpurified iron salt solution and an organic phase to obtain a purified iron salt solution;
(3) Adding a precipitator into the ferric salt solution until no precipitate is generated, filtering, washing the precipitate, drying, and roasting in a muffle furnace to obtain a high-purity ferric oxide product.
Preferably, the iron oxide is one or more of iron ore with the iron content of more than 25%, iron scale and iron-containing slag.
Preferably, the weight ratio of the iron oxide to the carbonate in the step (1) is (1-5) to (1-5); the heating rate is 20-50 deg.C/min.
Preferably, the carbonate is one or a mixture of more than two of sodium carbonate, sodium bicarbonate and potassium carbonate.
Preferably, the acid solution in the step (2) is one of nitric acid, hydrochloric acid and sulfuric acid; the volume concentration of the acid solution is 20-60%.
Preferably, the reaction time of the sodium ferrite and the acid solution in the step (2) is 25-40 ℃ and the reaction time is 30-300 minutes.
Preferably, the component of the iron salt solution unpurified in the step (2) is that the content of the iron element is Fe2O3＝0.1-35g/L、SiO2The content of (A) is 0.05-2.5g/L, Al2O3The content of (A) is 0.06-3.5g/L, MnO2The content of CaO is 0.05-6.5g/L and the content of CaO is 0.01-6.5 g/L.
Preferably, the organic phase in the extraction process is prepared from sulfonated kerosene and an extracting agent according to the volume ratio of (1:2) - (1:2), and the extracting agent is at least one of N235, P204 and TBP.
Preferably, the specific operation of step (3) is: washing the precipitate with anhydrous ethanol, and drying at 60-80 deg.C for 30-60 min; the filtrate is washed by deionized water and then recycled.
Preferably, the roasting temperature is controlled to be 500-650 ℃, the roasting time is 0.5-3h, and the furnace cooling is carried out.
Preferably, the precipitant is at least one of sodium hydroxide, ammonia water, or oxalic acid.
The invention also provides the high-purity iron oxide prepared by the method.
The invention has the beneficial effects that:
the invention takes iron oxide such as iron oxide and the like as raw materials, firstly prepares the iron oxide into sodium ferrite, then dissolves the sodium ferrite into iron salt solution, converts iron ions into ferric hydroxide precipitate after purification, and then calcines the ferric oxide to obtain high-purity ferric oxide. The iron element in the raw material can be greatly enriched by converting the iron oxide into the sodium ferrite, and the obtained iron oxide product has the purity higher than 99.9 percent, stable quality and high performance.
Detailed Description
Hereinafter, embodiments of the present invention will be described in detail. The following examples are only for illustrating the technical solutions of the present invention more clearly, and therefore are only examples, and the protection scope of the present invention is not limited thereby.
It is to be noted that, unless otherwise specified, technical or scientific terms used herein shall have the ordinary meaning as understood by those skilled in the art to which the invention pertains.
Example 1
The preparation method comprises the following steps:
(1) uniformly mixing 120 g of iron ore with 55% of iron content and 50 g of sodium carbonate, putting the mixture into a graphite crucible, putting the graphite crucible into a muffle furnace for heating, heating to 1200 ℃, preserving heat for 1 hour, and cooling along with the furnace to obtain sodium ferrite;
preparing 100ml of hydrochloric acid solution with the volume concentration of 20%, adding the sodium ferrite prepared in the step (1), stirring for 60 minutes at 40 ℃, filtering, and adjusting the pH of the solution to 2 by using ammonia water to obtain ferric chloride solution;
(2) mixing 1.5mol/L N235 and sulfonated kerosene according to the proportion of 1:1 to be used as an extraction organic phase, and performing extraction, washing and back extraction in fractional extraction tanks of extraction 3 level, washing 8 level and back extraction 5 level, wherein the flow ratio is as follows: an organic phase, namely rare earth solution and washing liquid are 2.5:1:0.4, and purified ferric chloride solution is obtained;
(3) adding ammonia water with the volume concentration of 20% into the back extraction organic phase, stirring for 3 minutes, standing for more than 2 hours until no precipitate is generated, filtering, washing the precipitate for 2 times by using absolute ethyl alcohol, drying for 30 minutes at 75 ℃, sending the precipitate into a muffle furnace, and roasting for 2 hours at 600 ℃ to obtain a high-purity iron oxide product.
Example 2
(1) Uniformly mixing 150 g of iron oxide sheet with iron content of 70% and 45 g of sodium carbonate, putting the mixture into a graphite crucible, putting the graphite crucible into a muffle furnace for heating, heating to 1200 ℃, preserving heat for 1 hour, and cooling along with the furnace to obtain sodium ferrite;
(2) preparing 100ml of sulfuric acid solution with the volume concentration of 30%, adding the sodium ferrite prepared in the step (1), stirring for 120 minutes at the temperature of 30 ℃, filtering, and adjusting the pH value of the solution to 1.5 by using ammonia water to obtain ferric sulfate solution; mixing 1.5mol/L P204 and sulfonated kerosene according to a ratio of 1:1 to obtain an extraction organic phase, and performing extraction, washing and back extraction in fractional extraction tanks of extraction 6, washing 9 and back extraction 4 stages, wherein the flow ratio is as follows: an organic phase, namely a rare earth solution and a washing solution are 2.8:1:0.6, and a purified ferric sulfate solution is obtained;
(3) adding ammonia water with the volume concentration of 25% into the back extraction organic phase, stirring for 3 minutes, standing for more than 2 hours until no precipitate is generated, filtering, washing the precipitate for 2 times by using absolute ethyl alcohol, drying for 30 minutes at 80 ℃, sending the precipitate into a muffle furnace, and roasting for 3 hours at 550 ℃ to obtain a high-purity iron oxide product.
Example 3
(1) Uniformly mixing 200 g of converter iron slag with 25% of iron content and 60 g of sodium carbonate, putting the mixture into a graphite crucible, putting the graphite crucible into a muffle furnace for heating, heating to 1200 ℃, preserving heat for 1 hour, and cooling along with the furnace to obtain sodium ferrite;
(2) Preparing 100ml of nitric acid solution with the volume concentration of 40%, adding the sodium ferrite prepared in the step (1), stirring for 180 minutes at 40 ℃, filtering, and adjusting the pH of the solution to 2.5 by using ammonia water to obtain ferric nitrate solution; mixing 1.5mol/L TBP and sulfonated kerosene according to a ratio of 1:1 to obtain an extraction organic phase, and performing extraction, washing and back extraction in fractional extraction tanks of extraction 5, washing 9 and back extraction 3 stages, wherein the flow ratio is as follows: an organic phase, namely rare earth solution and washing liquid are 3.2:1:0.8, and purified ferric nitrate solution is obtained;
(3) adding ammonia water with the volume concentration of 10% into the back extraction organic phase, stirring for 3 minutes, standing for more than 2 hours until no precipitate is generated, filtering, washing the precipitate for 2 times by using absolute ethyl alcohol, drying for 30 minutes at 80 ℃, sending the precipitate into a muffle furnace, and roasting for 0.5 hour at 500 ℃ to obtain a high-purity iron oxide product.
Example 4
(1) Uniformly mixing 100 g of iron oxide sheet with iron content of 75% and 65 g of sodium carbonate, putting the mixture into a graphite crucible, putting the graphite crucible into a muffle furnace for heating, heating to 1200 ℃, preserving heat for 1 hour, and cooling along with the furnace to obtain sodium ferrite;
(2) preparing 100ml of hydrochloric acid solution with the volume concentration of 60%, adding the sodium ferrite prepared in the step (1), stirring for 60 minutes at 30 ℃, filtering, and adjusting the pH of the solution to 2.5 by using ammonia water to obtain ferric chloride solution; mixing 1.5mol/L N235 and sulfonated kerosene according to the proportion of 1:1 to be used as an extraction organic phase, and performing extraction, washing and back extraction in fractional extraction tanks of extraction 6 stages, washing 9 stages and back extraction 4 stages, wherein the flow ratio is as follows: an organic phase, namely rare earth solution and washing liquid are 3.4:1:0.8, and purified ferric chloride solution is obtained;
(3) Adding ammonia water with the volume concentration of 20% into the back extraction organic phase, stirring for 3 minutes, standing for more than 2 hours until no precipitate is generated, filtering, washing the precipitate for 2 times by using absolute ethyl alcohol, drying for 30 minutes at 80 ℃, sending the precipitate into a muffle furnace, and roasting for 2 hours at 600 ℃ to obtain a high-purity iron oxide product.
The calcined high purity iron oxide was weighed and subjected to elemental analysis, the overall process iron yield and the product purity were analyzed, and the statistics of the results are shown in table 1.
TABLE 1 Total Process iron element yield and high purity iron oxide purity
| Iron oxide weight (g) | Purity of iron oxide | Overall yield of iron element | |
| Example 1 | 120 | 99.4％ | 96.8％ |
| Example 2 | 150 | 99.2％ | 95.4％ |
| Example 3 | 200 | 99.0％ | 96.2％ |
| Example 4 | 100 | 99.2％ | 95.1％ |
As can be seen from the above table, the yield of the iron element in the whole process is more than 95%, and the purity of the obtained iron oxide is more than 99%.
Finally, it should be noted that: the above embodiments are only used to illustrate the technical solution of the present invention, and not to limit the same; while the invention has been described in detail and with reference to the foregoing embodiments, it will be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; such modifications and substitutions do not depart from the spirit and scope of the present invention, and they should be construed as being included in the following claims and description.
Claims (10)
1. A method for preparing high-purity iron oxide by using iron oxide is characterized by comprising the following steps:
(1) uniformly mixing iron oxide and carbonate, putting the mixture into a muffle furnace for heating, heating to 1200 ℃, preserving heat for 1-1.5 hours, and cooling to obtain sodium ferrite;
(2) dissolving sodium ferrite with an acid solution to obtain an unpurified iron salt solution, adjusting the pH value of the solution to be between 0 and 2.5, and extracting, washing and back-extracting the unpurified iron salt solution and an organic phase to obtain a purified iron salt solution;
(3) adding a precipitator into the ferric salt solution until no precipitate is generated, filtering, washing the precipitate, drying, and roasting in a muffle furnace to obtain a high-purity ferric oxide product.
2. The method for preparing high-purity iron oxide by using the iron oxide as claimed in claim 1, wherein the iron oxide is one or more of iron ore with iron content of more than 25%, iron scale and iron-containing slag.
3. The method for preparing high purity iron oxide using iron oxide as claimed in claim 1, wherein the weight ratio of iron oxide to carbonate in step (1) is (1-5) to (1-5); the heating rate is 20-50 deg.C/min.
4. The method for preparing high-purity iron oxide by using iron oxide as claimed in claim 1, wherein the carbonate is one or a mixture of more than two of sodium carbonate, sodium bicarbonate and potassium carbonate.
5. The method for preparing high-purity iron oxide using iron oxide according to claim 1, wherein the acid solution in the step (2) is one of nitric acid, hydrochloric acid and sulfuric acid; the volume concentration of the acid solution is 20-60%.
6. The method for preparing high-purity iron oxide using iron oxide according to claim 1, wherein the reaction time of the sodium ferrite with the acid solution in the step (2) is 25-40 ℃ and the reaction time is 30-300 minutes.
7. The method for preparing high-purity iron oxide by using iron oxide as claimed in claim 1, wherein the unpurified solution of iron salt in step (2) contains Fe element in an amount of Fe2O3＝0.1-35g/L、SiO2The content of (A) is 0.05-2.5g/L, Al2O3The content of (A) is 0.06-3.5g/L, MnO2The content of CaO is 0.05-6.5g/L and the content of CaO is 0.01-6.5 g/L.
8. The method for preparing high-purity iron oxide by using iron oxide as claimed in claim 1, wherein the organic phase in the extraction process of step (2) is prepared by mixing sulfonated kerosene and an extracting agent according to the volume ratio of (1-2): (1-2), wherein the extracting agent is at least one of N235, P204 and TBP.
9. The method for preparing high-purity iron oxide by using iron oxide as claimed in claim 7, wherein the specific operation of step (3) is as follows: washing the precipitate with anhydrous ethanol, and drying at 60-80 deg.C for 30-60 min; washing the filtrate with deionized water and recycling;
Controlling the temperature to be 500-650 ℃ during roasting, controlling the roasting time to be 0.5-3h, and cooling along with the furnace;
the precipitator is at least one of sodium hydroxide, ammonia water or oxalic acid.
10. High purity iron oxide prepared by the process of any one of claims 1 to 9.
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113479937A (en) * | 2021-07-02 | 2021-10-08 | 内蒙古科技大学 | Method for preparing spheroidal iron oxide |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN113479937A (en) * | 2021-07-02 | 2021-10-08 | 内蒙古科技大学 | Method for preparing spheroidal iron oxide |
| CN113479937B (en) * | 2021-07-02 | 2023-01-03 | 内蒙古科技大学 | Method for preparing spheroidal iron oxide |
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