CN114368767A - Method for removing iron in Bayer process for preparing alumina - Google Patents

Method for removing iron in Bayer process for preparing alumina Download PDF

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Publication number
CN114368767A
CN114368767A CN202210055399.8A CN202210055399A CN114368767A CN 114368767 A CN114368767 A CN 114368767A CN 202210055399 A CN202210055399 A CN 202210055399A CN 114368767 A CN114368767 A CN 114368767A
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iron
active
sodium aluminate
slag
mother liquor
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晏华钎
戴静
卞磊
熊德芬
王花
孔令丽
朱杨昆
罗俊松
杜银江
王治国
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Yunnan Wenshan Aluminum Co ltd
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Yunnan Wenshan Aluminum Co ltd
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    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01F—COMPOUNDS OF THE METALS BERYLLIUM, MAGNESIUM, ALUMINIUM, CALCIUM, STRONTIUM, BARIUM, RADIUM, THORIUM, OR OF THE RARE-EARTH METALS
    • C01F7/00—Compounds of aluminium
    • C01F7/02—Aluminium oxide; Aluminium hydroxide; Aluminates
    • C01F7/04—Preparation of alkali metal aluminates; Aluminium oxide or hydroxide therefrom
    • C01F7/06—Preparation of alkali metal aluminates; Aluminium oxide or hydroxide therefrom by treating aluminous minerals or waste-like raw materials with alkali hydroxide, e.g. leaching of bauxite according to the Bayer process
    • C01F7/0646—Separation of the insoluble residue, e.g. of red mud
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01F—COMPOUNDS OF THE METALS BERYLLIUM, MAGNESIUM, ALUMINIUM, CALCIUM, STRONTIUM, BARIUM, RADIUM, THORIUM, OR OF THE RARE-EARTH METALS
    • C01F7/00—Compounds of aluminium
    • C01F7/02—Aluminium oxide; Aluminium hydroxide; Aluminates
    • C01F7/04—Preparation of alkali metal aluminates; Aluminium oxide or hydroxide therefrom
    • C01F7/06—Preparation of alkali metal aluminates; Aluminium oxide or hydroxide therefrom by treating aluminous minerals or waste-like raw materials with alkali hydroxide, e.g. leaching of bauxite according to the Bayer process
    • C01F7/066—Treatment of the separated residue
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01F—COMPOUNDS OF THE METALS BERYLLIUM, MAGNESIUM, ALUMINIUM, CALCIUM, STRONTIUM, BARIUM, RADIUM, THORIUM, OR OF THE RARE-EARTH METALS
    • C01F7/00—Compounds of aluminium
    • C01F7/02—Aluminium oxide; Aluminium hydroxide; Aluminates
    • C01F7/04—Preparation of alkali metal aluminates; Aluminium oxide or hydroxide therefrom
    • C01F7/14—Aluminium oxide or hydroxide from alkali metal aluminates

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  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Geology (AREA)
  • Inorganic Chemistry (AREA)
  • General Life Sciences & Earth Sciences (AREA)
  • Geochemistry & Mineralogy (AREA)
  • Analytical Chemistry (AREA)
  • Compounds Of Alkaline-Earth Elements, Aluminum Or Rare-Earth Metals (AREA)

Abstract

The invention provides a method for removing iron in a Bayer process for preparing alumina, and relates to the technical field of alumina preparation. On one hand, the method utilizes positive and negative ions in the active dissolved slag to destroy the electric structure of the iron sol, so that iron is more easily precipitated; on the other hand, the non-coagulated iron sol is adsorbed by a porous structure which utilizes active dissolved slag. Under the dual function, reach better deironing effect. In addition, the active dissolved slag is an intermediate product in the aluminum ash treatment process, and the resource recycling of the aluminum ash is better realized by utilizing the active dissolved slag, so that the method has certain environmental protection significance. The method is simple to operate, high in feasibility and high in practical value.

Description

Method for removing iron in Bayer process for preparing alumina
Technical Field
The invention relates to the technical field of alumina preparation, in particular to a method for removing iron in a Bayer process for preparing alumina.
Background
The iron in the sodium aluminate solution is mainly from bauxite, and the corrosion of the equipment also increases the iron content in the solution. In the bayer process for producing alumina, the iron minerals in bauxite are mostly removed by sedimentation in the form of red mud, but some small particles of very fine iron compounds cannot be removed and enter the solution. When the iron content in the sodium aluminate solution is too high, aluminum hydroxide enters in the seed precipitation process to cause the content of iron aluminum oxide to exceed the standard, and aluminum ingots enter in the electrolysis process. At present, the domestic metallurgical grade alumina first-grade product requires Fe2O3Less than 0.020%, but with the development of electrolytic aluminum industry and multi-variety alumina industry, the purity and whiteness of the product are difficult to meet the quality requirements, so the requirement on the iron content in the alumina is higher and higher, and the iron in the sodium aluminate solution must be removed to control the iron content in a lower range.
Disclosure of Invention
The invention aims to provide a method for removing iron in a Bayer process for preparing alumina, which has the advantages of simple operation and high feasibility, and can effectively remove the iron content in a sodium aluminate solution and improve the product quality of the alumina.
The embodiment of the invention is realized by the following steps:
a method for removing iron in a Bayer process for preparing alumina comprises the following steps:
mixing the crude sodium aluminate solution obtained after the separation of the dissolved slurry with the active dissolved slag, and carrying out sedimentation separation to obtain refined sodium aluminate solution;
wherein the active dissolving out slag is the solid residue left after the decomposition mother liquor in the process of preparing the aluminum oxide by the Bayer process and the aluminum ash are mixed and dissolved out.
The embodiment of the invention has the beneficial effects that:
the invention provides a method for removing iron in a Bayer process for preparing alumina, which is characterized in that crude sodium aluminate solution obtained after separation of dissolved slurry is mixed with active dissolved slag, and then precipitation separation is carried out to obtain refined sodium aluminate solution. On one hand, the method utilizes positive and negative ions in the active dissolved slag to destroy the electric structure of the iron sol, so that iron is more easily precipitated; on the other hand, the non-coagulated iron sol is adsorbed by a porous structure which utilizes active dissolved slag. Under the dual function, reach better deironing effect. In addition, the active dissolved slag is an intermediate product in the aluminum ash treatment process, and the resource recycling of the aluminum ash is better realized by utilizing the active dissolved slag, so that the method has certain environmental protection significance. The method is simple to operate, high in feasibility and high in practical value.
Detailed Description
In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. The examples, in which specific conditions are not specified, were conducted under conventional conditions or conditions recommended by the manufacturer. The reagents or instruments used are not indicated by the manufacturer, and are all conventional products available commercially.
The method for removing iron in the process of preparing alumina by a Bayer process according to the embodiment of the invention is specifically described below.
The embodiment of the invention provides a method for removing iron in a process of preparing alumina by a Bayer process, which comprises the following steps:
mixing the crude sodium aluminate solution obtained after the separation of the dissolved slurry with the active dissolved slag, and carrying out sedimentation separation to obtain refined sodium aluminate solution;
wherein the active dissolving out slag is the solid residue left after the decomposition mother liquor in the process of preparing the aluminum oxide by the Bayer process and the aluminum ash are mixed and dissolved out.
In the Bayer process of producing alumina, bauxite is first crushed and then wet milled and leached with circular mother liquor, and the leached ore pulp is diluted, settled and separated to obtain coarse sodium aluminate liquid and red mud slurry. Although most of the iron in the digestion slurry is discharged into the red mud slurry, part of the fine iron sol remains in the sodium aluminate crude liquor. In the subsequent flow, the crude sodium aluminate solution is filtered to obtain refined sodium aluminate solution, the refined sodium aluminate solution is subjected to seed crystal decomposition and sedimentation separation to obtain decomposition mother liquor and aluminum hydroxide, and the aluminum hydroxide is calcined to obtain aluminum oxide. Because the diameter of the iron sol is smaller than that of the filter holes, the iron sol can not be removed in the filtering process, and the iron sol can continuously enter the sodium aluminate fine solution and even the aluminum hydroxide and finally enter the finished product of aluminum oxide, thereby greatly influencing the quality of the aluminum oxide.
The inventor of the application discovers through long-term production practice that the quality of the alumina can be effectively improved by adding the iron removing agent into the sodium aluminate crude liquid to remove the iron sol. In the selection of the iron remover, the main problem that the skilled person in the art seeks is how to find a suitable iron remover by not only ensuring the iron removing effect, but also considering various problems such as cost, operability and the like.
The aluminum ash is scum floating on the aluminum liquid of the electrolytic bath generated in the aluminum electrolysis process. The aluminum ash is mainly divided into primary aluminum ash (white ash) and secondary aluminum ash (black ash). The primary aluminum ash is aluminum slag generated in the aluminum production process of original aluminum, and the primary aluminum ash mainly comprises metallic aluminum and aluminum oxide, wherein the content of the metallic aluminum can reach 30-70%. In the prior art, more aluminum ash is treated in a landfill mode, so that resource waste is caused on one hand, and environmental problems are caused on the other hand. The inventor of the application regards the intermediate product-active slag that dissolves in the aluminium ash processing procedure as the iron removing agent, when deironing, can also retrieve the aluminium in the aluminium ash and recycle, increases the output of aluminium oxide.
The decomposition mother liquor is a liquid phase component remained after crystal seed decomposition and sedimentation separation of the sodium aluminate fine liquor are carried out in the process of producing the aluminum oxide by the Bayer process. The decomposition mother liquor mainly contains sodium aluminate, aluminum hydroxide and sodium carbonate generated by reaction, which are not separated out. In general, the decomposition mother liquor is evaporated to separate out sodium carbonate crystals, and the residual liquid phase is used as circulating mother liquor to be conveyed to a wet grinding link of bauxite to recycle aluminum element in the bauxite. In the invention, after the aluminum ash is treated by the decomposition mother liquor, residual sodium aluminate and aluminum hydroxide in the decomposition mother liquor are also recycled, thereby further increasing the yield of aluminum oxide.
Wherein the active digestion slag contains 20-25 wt% of NaAlSiO420 to 30 weight percent of alpha-Al2O33 to 8 weight percent of MgAl2O43 to 8 weight percent of NaAl11O1730wt% -40 wt% of Al (OH)3And 2wt% -6 wt% of K11Si12Al12O48. The above-mentioned component contents may fluctuate depending on the component differences of the aluminum ash. Wherein, a large amount of positive and negative ions such as sodium, potassium, hydroxyl and the like in the active dissolving residues can damage the electric structure of the iron sol, so that iron is more easily precipitated. In addition thereto, NaAlSiO4，K11Si12Al12O48Also known as zeolites, the porous structure of which is effective for adsorption of the uncoalesced iron sol. Under the above-mentioned dual function, reach better deironing effect.
Optionally, the mass volume ratio of the aluminum ash to the decomposition mother liquor is 250-300 g/L. The alkali ratio of the decomposition mother liquor is 2.50-3.00. Within the proportion range, the aluminum ash has better dissolution effect, and the obtained active dissolution slag has better iron removal effect.
In addition, the active dissolved slag is obtained by mixing the decomposition mother liquor with aluminum ash and then carrying out closed reaction at 100-150 ℃ for dissolution. At the temperature, the activation effect of the active dissolved slag is better, and a more ideal iron removal effect can be achieved.
Further, in the embodiment of the invention, the mass-to-volume ratio of the active dissolving slag to the sodium aluminate crude liquid is 1-5 g/L. The inventor finds that the required iron removal effect cannot be achieved when the mass-volume ratio is too low; when the mass-to-volume ratio is too high, the iron removal effect can be achieved, but most of other ions are introduced, the precipitation effect is not ideal, and the quality of alumina is also affected. Under comprehensive consideration, the iron removal effect of the active dissolved slag is better within the proportion range of the mass-volume ratio of 1-5 g/L.
Optionally, the temperature for settling separation after mixing the sodium aluminate crude liquid and the active digestion residues is 80-100 ℃, and the time is 3-10 min. Under the sedimentation condition, the active dissolved slag and the iron sol can fully act, and a better sedimentation effect is achieved.
In addition, the method also comprises the step of filtering after the sedimentation separation of the crude sodium aluminate solution and the active dissolved-out slag is finished to obtain the refined sodium aluminate solution. After the iron sol and the active dissolved slag act, the colloid state is destroyed, but the formed particles can be suspended in the solution, and at this time, a filtering link can be added to remove suspended particles, so that a better iron removal effect is achieved.
The features and properties of the present invention are described in further detail below with reference to examples.
Example 1
The embodiment provides a method for removing iron in a Bayer process for preparing alumina, which comprises the following steps:
s1, adding the crushed bauxite into the circulating mother liquor to carry out wet grinding and dissolution to obtain dissolved ore pulp.
S2, diluting the dissolved ore pulp, settling and separating to obtain a sodium aluminate crude liquid and red mud slurry.
And S3, mixing the active dissolved slag and the sodium aluminate crude liquid according to the mass-volume ratio of 1 g/L, then settling for 3 min at 100 ℃, and separating to obtain sodium aluminate fine liquid.
Wherein the active dissolving out slag is solid residue remained after mixing decomposition mother liquor in the process of preparing alumina by a Bayer process with aluminum ash and dissolving out at 150 ℃. The mass volume ratio of the aluminum ash to the decomposition mother liquor is 270 g/L. The alkali ratio of the decomposition mother liquor was 2.50.
The active digestion slag contains 23.46wt% of NaAlSiO421.92wt% of alpha-Al2O34.97wt% of MgAl2O44.22wt% of NaAl11O1733.89wt% of Al (O)H)3And 3.97wt% of K11Si12Al12O48。
S4, decomposing the sodium aluminate fine liquid by using seed crystals to obtain aluminum hydroxide slurry, and further settling and separating to obtain aluminum hydroxide and decomposition mother liquor.
S5, evaporating the decomposed mother liquor, separating sodium carbonate to obtain circulating mother liquor, and conveying the circulating mother liquor back to the bauxite wet grinding process.
S6, calcining the aluminum hydroxide to obtain the aluminum oxide.
Example 2
The embodiment provides a method for removing iron in a Bayer process for preparing alumina, which comprises the following steps:
s1, adding the crushed bauxite into the circulating mother liquor to carry out wet grinding and dissolution to obtain dissolved ore pulp.
S2, diluting the dissolved ore pulp, settling and separating to obtain a sodium aluminate crude liquid and red mud slurry.
And S3, mixing the active dissolved slag and the sodium aluminate crude liquid according to the mass-volume ratio of 3 g/L, then settling for 10 min at 80 ℃, and separating to obtain sodium aluminate fine liquid.
Wherein the active dissolving out slag is solid residue remained after mixing decomposition mother liquor in the Bayer process for preparing alumina with aluminum ash and dissolving out at 120 ℃. The mass volume ratio of the aluminum ash to the decomposition mother liquor is 250 g/L. The alkali ratio of the decomposition mother liquor was 2.50.
The active digestion slag contains 22.74wt% of NaAlSiO423.49wt% of alpha-Al2O33.72wt% of MgAl2O47.31wt% of NaAl11O1738.94wt% of Al (OH)3And 5.27 wt.% of K11Si12Al12O48。
S4, decomposing the sodium aluminate fine liquid by using seed crystals to obtain aluminum hydroxide slurry, and further settling and separating to obtain aluminum hydroxide and decomposition mother liquor.
S5, evaporating the decomposed mother liquor, separating sodium carbonate to obtain circulating mother liquor, and conveying the circulating mother liquor back to the bauxite wet grinding process.
S6, calcining the aluminum hydroxide to obtain the aluminum oxide.
Example 3
The embodiment provides a method for removing iron in a Bayer process for preparing alumina, which comprises the following steps:
s1, adding the crushed bauxite into the circulating mother liquor to carry out wet grinding and dissolution to obtain dissolved ore pulp.
S2, diluting the dissolved ore pulp, settling and separating to obtain a sodium aluminate crude liquid and red mud slurry.
And S3, mixing the active dissolved slag and the crude sodium aluminate solution according to the mass-to-volume ratio of 5 g/L, then settling for 6 min at 90 ℃, and separating to obtain the refined sodium aluminate solution.
Wherein the active dissolving out slag is solid residue remained after mixing decomposition mother liquor in the Bayer process for preparing alumina with aluminum ash and dissolving out at 130 ℃. The mass volume ratio of the aluminum ash to the decomposition mother liquor is 270 g/L. The alkali ratio of the decomposition mother liquor was 2.75.
The active digestion slag contains 24.61wt% of NaAlSiO420.23wt% of alpha-Al2O33.57wt% of MgAl2O45.93wt% of NaAl11O1731.28wt% of Al (OH)3And 2.58 wt.% of K11Si12Al12O48。
S4, decomposing the sodium aluminate fine liquid by using seed crystals to obtain aluminum hydroxide slurry, and further settling and separating to obtain aluminum hydroxide and decomposition mother liquor.
S5, evaporating the decomposed mother liquor, separating sodium carbonate to obtain circulating mother liquor, and conveying the circulating mother liquor back to the bauxite wet grinding process.
S6, calcining the aluminum hydroxide to obtain the aluminum oxide.
Example 4
The embodiment provides a method for removing iron in a Bayer process for preparing alumina, which comprises the following steps:
s1, adding the crushed bauxite into the circulating mother liquor to carry out wet grinding and dissolution to obtain dissolved ore pulp.
S2, diluting the dissolved ore pulp, settling and separating to obtain a sodium aluminate crude liquid and red mud slurry.
S3, mixing the active dissolved slag and the crude sodium aluminate solution according to the mass-to-volume ratio of 5 g/L, then settling for 3 min at 100 ℃, and then filtering and separating to obtain the refined sodium aluminate solution.
Wherein the active dissolving out slag is solid residue remained after mixing decomposition mother liquor in the process of preparing alumina by a Bayer process with aluminum ash and dissolving out at 150 ℃. The mass volume ratio of the aluminum ash to the decomposition mother liquor is 300 g/L. The alkali ratio of the decomposition mother liquor was 2.95.
The active digestion slag contains 24.37wt% of NaAlSiO423.13wt% of alpha-Al2O34.81wt% of MgAl2O46.24wt% of NaAl11O1733.95wt% Al (OH)3And 4.13wt% of K11Si12Al12O48。
S4, decomposing the sodium aluminate fine liquid by using seed crystals to obtain aluminum hydroxide slurry, and further settling and separating to obtain aluminum hydroxide and decomposition mother liquor.
S5, evaporating the decomposed mother liquor, separating sodium carbonate to obtain circulating mother liquor, and conveying the circulating mother liquor back to the bauxite wet grinding process.
S6, calcining the aluminum hydroxide to obtain the aluminum oxide.
Comparative example 1
This comparative example 1 provides a method for removing iron in a bayer process for producing alumina, which has substantially the same operational steps as in example 1, except that the amount of the leaching active slag was replaced with the same amount of aluminum hydroxide.
Comparative example 2
The comparative example 2 provides a method for removing iron in a bayer process for producing alumina, which has substantially the same operation steps as those of the example 2, except that the amount of the dissolved active slag is replaced with the same amount of aluminum hydroxide.
Comparative example 3
This comparative example 3 provides a method for removing iron in a bayer process for producing alumina, which has substantially the same operational steps as in example 3, except that the amount of the leaching active slag was replaced with the same amount of aluminum hydroxide.
Comparative example 4
This comparative example 4 provides a method for removing iron in a bayer process for producing alumina, which has substantially the same operational steps as in example 4, except that the amount of the leaching active slag was replaced with the same amount of aluminum hydroxide.
Test examples
The iron removal is carried out by adopting the methods of examples 1 to 4 and comparative examples 1 to 4, and the iron contents in the sodium aluminate concentrate and the final alumina product are respectively measured (both are converted into Fe)2O3Metering), and the iron removal rate was calculated using the amount of decrease in iron content of the examples or comparative examples from the blank with no iron remover treatment as the blank, and the calculation results are shown in table 1.
TABLE 1 iron removal test results
Iron content in sodium aluminate concentrate (g/L) Iron removal Rate (%) Iron content (wt%) of alumina product
Blank example 0.087 - 0.022
Example 1 0.067 22.98 0.017
Example 2 0.062 28.74 0.016
Example 3 0.059 32.18 0.015
Example 4 0.050 42.52 0.013
Comparative example 1 0.081 6.90 0.021
Comparative example 2 0.078 10.34 0.020
Comparative example 3 0.076 12.64 0.020
Comparative example 4 0.066 24.14 0.017
As can be seen from table 1, the iron removal rate of the iron removal method provided in the embodiment of the present invention can reach 22.98% to 32.18% (examples 1 to 3) under the condition of natural settling, and in contrast, if aluminum hydroxide is used for iron removal, the iron removal rate is only up to 12.3% at the highest under the same measurement (comparative example 3). The embodiment of the invention has obvious iron removal effect. Further, in the example of the present invention, the iron removal rate can be increased to 42.52% by adding a filtration step after natural settling (example 4). In contrast, when aluminum hydroxide is used as the iron remover, the iron removal rate of 24.14% (comparative example 4) can be achieved even if the filtering process is added, and the effect comparison is obvious. In addition, the iron removal method provided by the embodiment of the invention can reduce the iron content in the alumina product to be below 0.020wt%, thereby meeting the requirement of domestic metallurgical grade alumina first-grade products.
In conclusion, the invention provides a method for removing iron in a process of preparing alumina by a Bayer process, which mixes the crude sodium aluminate solution obtained after red mud separation with active dissolved slag, and carries out sedimentation separation to obtain refined sodium aluminate solution. On one hand, the method utilizes positive and negative ions in the active dissolved slag to destroy the electric structure of the iron sol, so that iron is more easily precipitated; on the other hand, the non-coagulated iron sol is adsorbed by a porous structure which utilizes active dissolved slag. Under the dual function, reach better deironing effect. In addition, the active dissolved slag is an intermediate product in the aluminum ash treatment process, and the resource recycling of the aluminum ash is better realized by utilizing the active dissolved slag, so that the method has certain environmental protection significance. The method is simple to operate, high in feasibility and high in practical value.
The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims (8)

1. A method for removing iron in a Bayer process for preparing alumina is characterized by comprising the following steps:
mixing the crude sodium aluminate solution obtained after the separation of the dissolved slurry with the active dissolved slag, and carrying out sedimentation separation to obtain refined sodium aluminate solution;
wherein the active dissolving slag is solid residue left after mixing and dissolving decomposition mother liquor and aluminum ash in the process of preparing alumina by a Bayer process.
2. The method for removing iron in the process of preparing alumina by the Bayer process according to claim 1, wherein the active digestion residues comprise 20-25 wt% of NaAlSiO420 to 30 weight percent of alpha-Al2O33 to 8 weight percent of MgAl2O43 to 8 weight percent of NaAl11O1730wt% -40 wt% of Al (OH)3And 2wt% -6 wt% of K11Si12Al12O48。
3. The method for removing iron in the process of preparing alumina by the Bayer process according to claim 2, wherein the mass-volume ratio of the aluminum ash to the decomposition mother liquor is 250-300 g/L.
4. The method for removing iron in the process of preparing alumina by the Bayer process according to claim 3, wherein the alkali ratio of the decomposition mother liquor is 2.50-3.00.
5. The method for removing iron in the process of preparing alumina by the Bayer process according to claim 4, wherein the active dissolved slag is dissolved out by mixing the decomposition mother liquor and the aluminum ash and then carrying out a closed reaction at 100-150 ℃.
6. The method for removing iron in the process of preparing alumina by using the Bayer process as claimed in claim 1, wherein the mass-to-volume ratio of the active dissolved slag to the crude liquid of sodium aluminate is 1-5 g/L.
7. The method for removing iron in the process of preparing alumina by the Bayer process according to claim 6, wherein the temperature for settling separation after mixing the crude sodium aluminate solution and the active dissolved slag is 80-100 ℃ and the time is 3-10 min.
8. The method for removing iron in the process of preparing alumina by the Bayer process according to claim 6, further comprising filtering after the precipitation separation of the crude sodium aluminate solution and the active digestion residues is finished, so as to obtain the refined sodium aluminate solution.
CN202210055399.8A 2022-01-18 2022-01-18 Method for removing iron in Bayer process for preparing alumina Pending CN114368767A (en)

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Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101314476A (en) * 2008-06-27 2008-12-03 中国铝业股份有限公司 Separation purification method for iron ion in sodium aluminate solution
US20130343971A1 (en) * 2011-05-11 2013-12-26 Inner Mongolia Datang International Recycling Resource Development Co., Ltd. Method for co-producing alumina and activated calcium silicate from high-alumina fly ash
CN104843752A (en) * 2015-03-27 2015-08-19 大唐国际发电股份有限公司高铝煤炭资源开发利用研发中心 Method for removing iron from sodium aluminate solution
WO2018233690A1 (en) * 2017-06-23 2018-12-27 东北大学 Method for preparing sodium aluminate by treating bayer red mud by using one-step alkali heat process of andradite

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101314476A (en) * 2008-06-27 2008-12-03 中国铝业股份有限公司 Separation purification method for iron ion in sodium aluminate solution
US20130343971A1 (en) * 2011-05-11 2013-12-26 Inner Mongolia Datang International Recycling Resource Development Co., Ltd. Method for co-producing alumina and activated calcium silicate from high-alumina fly ash
CN104843752A (en) * 2015-03-27 2015-08-19 大唐国际发电股份有限公司高铝煤炭资源开发利用研发中心 Method for removing iron from sodium aluminate solution
WO2018233690A1 (en) * 2017-06-23 2018-12-27 东北大学 Method for preparing sodium aluminate by treating bayer red mud by using one-step alkali heat process of andradite

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Application publication date: 20220419