Bauxite dissolution method for improving gallium leaching rate

Abstract

Disclosed in the present disclosure is a bauxite dissolution method for improving a gallium leaching rate. The method comprises the following steps: providing bauxite with an alumogoethite content of more than 10%; coarsely crushing the bauxite and then ball milling same together with an additive and a circulating mother liquor to obtain a raw ore pulp; pre-desiliconizing and dissolving the raw ore pulp to obtain a dissolved ore pulp; subjecting the dissolved ore pulp to sedimentation separation to obtain a clarified liquor; subjecting the clarified liquor to seed decomposition to obtain a decomposed mother liquor; and adding an ion exchange resin to the decomposed mother liquor, so as to adsorb and recover gallium in the decomposed mother liquor, wherein the additive comprises an alkaline earth metal compound, the alkaline earth metal compound comprises at least one of calcium oxide, calcium hydroxide, magnesium oxide and magnesium hydroxide, and the temperature during the dissolution treatment is 260°C or higher.

Description

Bauxite digestion method for improving gallium leaching rate Cross-reference to Related Applications

[0001] This application claims priority to Chinese Patent Application No. 202410785752.7, filed on June 18, 2024, the entire contents of which are incorporated herein by reference. TECHNICAL FIELD

[0002] The present disclosure relates to the aluminum industry, and in particular to a bauxite digestion process. BACKGROUND

[0003] Gallium is an essential raw material for the production of high-tech products, and has a wide range of applications in the fields of semiconductors, optoelectronic materials, solar cells, alloy materials, and military industries. With the rapid development of downstream application industries of gallium, especially the rapid development of the semiconductor industry and the solar cell industry, the demand for metallic gallium will steadily increase in the future. Gallium is a dispersed metal and has no independent ore deposit, more than 90% of which is associated with bauxite. The content of gallium oxide in bauxite is generally 0.006% to 0.015%. In the production of alumina, gallium enters the sodium aluminate solution in the form of sodium gallate and accumulates during the recycling process. Therefore, more than 90% of the gallium in the world is currently extracted from the production process of alumina. The ion exchange resin adsorption method is commonly used to recover metallic gallium from the production of alumina from domestic bauxite, and the production technology is relatively mature.

[0004] In recent years, with the increasing import of bauxite, more and more alumina enterprises have adopted imported ore to produce alumina. The imported ore is mainly gibbsite bauxite, which has the characteristics of low temperature and easy dissolution, so low temperature digestion process is mostly used. However, it is calculated that under this process condition, the leaching rate of gallium in the ore is about 60%, and 40% of the gallium enters the red mud, causing waste. Currently, the technology for extracting gallium in the production of alumina from imported ore mainly involves research on recovery methods, including the removal of impurity ions, optimization of resin adsorption process, etc., but does not involve how to improve the leaching rate of gallium in the bauxite digestion process. SUMMARY

[0005] The technical problem of low leaching rate of gallium in bauxite is solved by using one or more embodiments of the present disclosure.

[0006] The bauxite leaching method for improving gallium leaching rate according to some embodiments of the present disclosure comprises the following steps: providing a bauxite, the bauxite has an aluminum goethite content greater than 10%; after the bauxite is coarsely broken, the bauxite is ball milled together with an additive and a circulating mother liquor to obtain an ore slurry; the ore slurry is subjected to pre-desilication and leaching treatment to obtain a leaching slurry; the leaching slurry is subjected to sedimentation separation to obtain a refined liquid, and the refined liquid is subjected to seed decomposition to obtain a decomposition mother liquor; ion exchange resin is added to the decomposition mother liquor to adsorb and recover gallium in the decomposition mother liquor; wherein the additive comprises an alkaline earth metal compound, the alkaline earth metal compound comprises at least one of an oxide of calcium, a hydroxide of calcium, an oxide of magnesium, and a hydroxide of magnesium, and the leaching treatment has a treatment temperature above 260 DEG C. BRIEF DESCRIPTION OF DRAWINGS

[0007] The accompanying drawings, which are incorporated herein and constitute part of the specification, illustrate embodiments consistent with the present disclosure and, together with the description, serve to explain the principles of the disclosure.

[0008] In order to more clearly illustrate the technical solutions in the embodiments of the present disclosure or the related art, the accompanying drawings needed to be used in the embodiments or the related art description will be briefly introduced. Obviously, those skilled in the art can obtain other drawings according to these drawings without any creative effort.

[0009] FIG. 1 shows a flowchart of a bauxite leaching method for improving gallium leaching rate according to some embodiments of the present disclosure. DETAILED DESCRIPTION

[0010] In order to make the objects, technical solutions and advantages of the embodiments of the present disclosure clearer, the technical solutions in the embodiments of the present disclosure will be described clearly and completely below with reference to the drawings in the embodiments of the present disclosure. Obviously, the described embodiments are only some of the embodiments of the present disclosure, rather than all the embodiments of the present disclosure. Based on the embodiments in the present disclosure, all other embodiments obtained by those skilled in the art without any creative effort fall within the scope of protection of the present disclosure.

[0011] Unless otherwise specifically defined, the terms used herein are understood as having the meanings commonly used in the art. Therefore, unless otherwise defined, all technical and scientific terms used herein have the same meanings as generally understood by those skilled in the art to which the present disclosure belongs. If there is a conflict, the present specification takes precedence.

[0012] Unless otherwise specifically stated, the various raw materials, reagents, instruments and equipment used in the present disclosure can be purchased from the market or can be prepared by existing methods.

[0013] In the related art, there is a technical problem of low gallium leaching rate in the bauxite leaching process.

[0014] The technical solution according to some embodiments of the present disclosure is to solve the above technical problem, and the general idea is as follows:

[0015] The bauxite leaching method for improving gallium leaching rate according to some embodiments of the present disclosure comprises the following steps:

[0016] S1: providing bauxite, the bauxite has an aluminum goethite content greater than 10%;

[0017] S2: after the bauxite is coarsely broken, the bauxite is ball milled together with an additive and a circulating mother liquor to obtain an ore slurry;

[0018] S3: the ore slurry is subjected to pre-desilication and leaching treatment to obtain a leaching slurry;

[0019] S4: the leaching slurry is subjected to sedimentation separation to obtain a refined liquid, and the refined liquid is subjected to seed decomposition to obtain a decomposition mother liquor;

[0020] S5: ion exchange resin is added to the decomposition mother liquor to adsorb and recover gallium in the decomposition mother liquor;

[0021] The additive comprises an alkaline earth metal compound, the alkaline earth metal compound comprises at least one of an oxide of calcium, a hydroxide of calcium, an oxide of magnesium, and a hydroxide of magnesium, and the treatment temperature of the leaching treatment is above 260 DEG C.

[0022] As understood by those skilled in the art, the circulating mother liquor is a commonly used raw material in the Bayer process for producing aluminum oxide, and has strong alkalinity, which can leach the aluminum-containing compounds in the bauxite to form a solution containing sodium metaaluminate. After the solution containing sodium metaaluminate is treated to precipitate aluminum hydroxide, the remaining liquid phase can be recycled and used again to leach the aluminum-containing compounds in the bauxite after being treated by evaporation and concentration, and thus is called a circulating mother liquor.

[0023] As understood by those skilled in the art, the purpose of the pre-desilication in step S3 is to make the silicon-containing minerals (mainly kaolinite) in the ore slurry react to form hydrated sodium aluminum silicate and enter the solid phase, so as to prevent the silicon-containing minerals from forming scabs in the subsequent leaching treatment process.

[0024] As understood by those skilled in the art, the leaching treatment in step S3 refers to leaching the aluminum-containing compounds with a strong base at high temperature.

[0025] As understood by those skilled in the art, the sedimentation separation in step S4 refers to a process of adding a flocculating agent to the leaching slurry to flocculate and settle the solid in the leaching slurry.

[0026] The skilled in the art can understand that the liquid obtained after the leaching slurry is separated by sedimentation in step S4 is referred to as refined sodium aluminate solution, simply referred to as refined liquid. The seed decomposition of the refined liquid refers to the process of forming a supersaturated sodium aluminate solution and causing the aluminum hydroxide in the supersaturated sodium aluminate solution to crystallize and precipitate under the conditions of cooling, stirring and adding seed crystals.

[0027] Titanium minerals (anatase and rutile) in the bauxite react to produce sodium titanate under alkaline conditions. The solubility of sodium titanate is small, and sodium titanate is a dense precipitate. The sodium titanate wrapped on the surface of the aluminum goethite can prevent the aluminum goethite from reacting with the alkali solution, so that the gallium element in the aluminum goethite is difficult to release. In some embodiments of the present disclosure, by making the additive at least one of calcium oxide, calcium hydroxide, magnesium oxide and magnesium hydroxide, the additive can react with the titanium mineral to generate calcium titanate or magnesium titanate, which can eliminate the influence of the titanium mineral on the aluminum goethite, promote the leaching reaction of the aluminum goethite, and release the gallium element in the aluminum goethite. In addition, the additive can change the reaction product of the silicon mineral from hydrated sodium aluminum silicate to hydrated garnet, thereby reducing the alkali consumption.

[0028] In some embodiments of the present disclosure, by adding an additive during the ball milling process, the additive includes at least one of calcium oxide, calcium hydroxide, magnesium oxide and magnesium hydroxide, so that the aluminum goethite in the bauxite is converted into hematite, and the silicon mineral reacts to generate hydrated garnet, thereby promoting the leaching of the gallium associated with the aluminum goethite and the silicon mineral, and also reducing the consumption.

[0029] In some embodiments of the present disclosure, the additive can be added in an amount of 2% to 6% of the mass of the bauxite.

[0030] The beneficial effect of controlling the amount of the additive to be 2% to 6% of the mass of the bauxite is that the conversion of the aluminum goethite in the bauxite to goethite can be effectively promoted, the gallium associated with the aluminum goethite can be dissolved out, and too many Ca and / or Mg ions can be avoided from being introduced, thereby avoiding increasing impurities in the raw ore slurry.

[0031] In some embodiments of the present disclosure, the caustic alkali concentration of the circulating mother liquor is above 200 g / L.

[0032] In some embodiments of the present disclosure, the caustic alkali concentration of the circulating mother liquor is 200 g / L to 300 g / L.

[0033] The beneficial effect of the caustic alkali concentration of the circulating mother liquor being 200 g / L to 300 g / L is that the alumina in the bauxite can be leached out at a higher leaching rate, and the circulating mother liquor can also maintain a low viscosity, so that the red mud obtained after the leaching slurry is separated by sedimentation can be more easily separated and settled.

[0034] In some embodiments of the present disclosure, the concentration of gallium in the circulating mother liquor is not higher than 0.3 g / L.

[0035] The beneficial effect of controlling the concentration of gallium in the circulating mother liquor to be not higher than 0.3 g / L is that 0.3 g / L is far lower than the equilibrium concentration of gallium in the circulating mother liquor, which is conducive to dissolving gallium in the bauxite at a higher dissolution rate.

[0036] In some embodiments of the present disclosure, the dissolution temperature of the dissolution treatment is 260-280°C.

[0037] The beneficial effect of the dissolution temperature of the dissolution treatment being 260-280°C is that it can make the goethite in the bauxite fully react, which is conducive to dissolving aluminum oxide and gallium in the bauxite at a higher dissolution rate, and at the same time, the dissolution treatment can be carried out at a reasonable energy consumption.

[0038] In some embodiments of the present disclosure, the dissolution time of the dissolution treatment is 60 min or more.

[0039] The beneficial effect of the dissolution time of the dissolution treatment being 60 min or more is that sufficient dissolution time can ensure that the goethite is converted into hematite as much as possible, which is conducive to improving the dissolution rate of gallium (Ga).

[0040] In some embodiments of the present disclosure, the bauxite includes at least one of gibbsite-type bauxite and gibbsite-boehmite mixed-type bauxite.

[0041] It is easy to understand that both the gibbsite-type bauxite and the gibbsite-boehmite mixed-type bauxite are commonly used bauxites, and each of them contains a large amount of goethite.

[0042] In some embodiments of the present disclosure, the pre-desilication includes the following steps: stirring the raw ore slurry at 80-105°C for 6-10 h.

[0043] The present disclosure will be further described below in conjunction with specific embodiments. It should be understood that these embodiments are only used to illustrate the present disclosure and not to limit the scope of the present disclosure. The experimental methods not specified in the following embodiments are generally determined according to the industry standards. If there is no corresponding industry standard, it is determined according to the general international standards, conventional conditions, or according to the conditions suggested by the manufacturer.

[0044] Embodiment 1

[0045] The present embodiment provides a method for improving the dissolution rate of gallium in bauxite, which includes the following steps:

[0046] S1: providing bauxite;

[0047] S2: coarsely crushing the bauxite and then ball-milling the bauxite together with an additive and a circulating mother liquor to obtain a raw ore slurry;

[0048] S3: The raw ore slurry is subjected to pre-desilication and leaching treatment to obtain a leached ore slurry;

[0049] S4: The leached ore slurry is subjected to sedimentation separation to obtain a refined liquid, and the refined liquid is subjected to seed decomposition to obtain a decomposition mother liquor;

[0050] S5: Ion exchange resin is added to the decomposition mother liquor to adsorb and recover gallium in the decomposition mother liquor.

[0051] The bauxite is an imported ore, and the contents of Al2O3, SiO2 and Fe2O3 are 42.50%, 2.26% and 28.88%, respectively, the content of gibbsite is 57.3%, the content of bayerite is 1.4%, and the content of aluminum goethite is 17%;

[0052] The additive in step S2 is an alkaline earth metal compound, and the alkaline earth metal oxide is specifically calcium oxide; the additive is added in an amount of 5% of the mass of the bauxite; the concentration of the caustic alkali in the circulating mother liquor is 230 g / L, and the concentration of gallium in the circulating mother liquor is 0.3 g / L;

[0053] The leaching temperature in step S3 is 260°C, and the leaching time is 60 min;

[0054] The ion exchange resin in step S5 is specifically LSC-600 ion exchange resin produced by Xi'an Lanxiao Science and Technology New Material Co., Ltd.;

[0055] It is detected that the leaching rate of gallium in the bauxite is 75%, and the leaching rate of aluminum oxide is 92%.

[0056] Example 2

[0057] The embodiment provides a method for improving the leaching rate of gallium in bauxite, comprising the following steps:

[0058] S1: Providing bauxite;

[0059] S2: After the bauxite is coarsely broken, the bauxite is subjected to ball milling together with an additive and a circulating mother liquor to obtain a raw ore slurry;

[0060] S3: The raw ore slurry is subjected to pre-desilication and leaching treatment to obtain a leached ore slurry;

[0061] S4: The leached ore slurry is subjected to sedimentation separation to obtain a refined liquid, and the refined liquid is subjected to seed decomposition to obtain a decomposition mother liquor;

[0062] S5: Ion exchange resin is added to the decomposition mother liquor to adsorb and recover gallium in the decomposition mother liquor.

[0063] The bauxite is an imported ore, and the contents of Al2O3, SiO2 and Fe2O3 are 42.50%, 2.26% and 28.88% respectively, the content of gibbsite is 57.3%, the content of bayerite is 1.4%, and the content of aluminum goethite is 17%;

[0064] The additive in step S2 is an alkaline earth metal compound, and the alkaline earth metal oxide is calcium oxide; the additive is added in an amount of 3% of the mass of the bauxite; the concentration of the caustic alkali in the circulating mother liquor is 230 g / L, and the concentration of gallium in the circulating mother liquor is 0.2 g / L;

[0065] The leaching treatment in step S3 is performed at a leaching temperature of 265 DEG C and a leaching time of 60 min;

[0066] The ion exchange resin in step S5 is LSC-600 ion exchange resin from Xi'an Lanxiao Science and Technology New Material Co., Ltd.

[0067] It is detected that the leaching rate of gallium in the bauxite is 81%, and the leaching rate of aluminum oxide is 92.5%.

[0068] Embodiment 3

[0069] The embodiment provides a method for improving the leaching rate of gallium in bauxite, comprising the following steps:

[0070] S1: providing bauxite;

[0071] S2: co-milling the bauxite after being coarsely broken with an additive and a circulating mother liquor to obtain an ore slurry;

[0072] S3: performing pre-desiliconization and leaching treatment on the ore slurry to obtain a leaching slurry;

[0073] S4: performing sedimentation separation on the leaching slurry to obtain a refined liquid, and performing seed decomposition on the refined liquid to obtain a decomposition mother liquor;

[0074] S5: adding an ion exchange resin to the decomposition mother liquor to adsorb and recover gallium in the decomposition mother liquor.

[0075] The bauxite is an imported ore, and the contents of Al2O3, SiO2 and Fe2O3 are 42.50%, 2.26% and 28.88% respectively, the content of gibbsite is 57.3%, the content of bayerite is 1.4%, and the content of aluminum goethite is 17%;

[0076] The additive in step S2 is an alkaline earth metal compound, and the alkaline earth metal oxide is calcium oxide; the additive is added in an amount of 3% of the mass of the bauxite; the concentration of the caustic alkali in the circulating mother liquor is 230 g / L, and the concentration of gallium in the circulating mother liquor is 0.2 g / L;

[0077] The leaching treatment in step S3 is performed at a leaching temperature of 265℃ and a leaching time of 60min;

[0078] The ion exchange resin in step S5 is specifically LSC-600 ion exchange resin from Xi'an Lanxiao Science and Technology New Material Co., Ltd.

[0079] It is detected that the leaching rate of gallium in the bauxite is 78%, and the leaching rate of aluminum oxide is 91%.

[0080] Example 4

[0081] The embodiment provides a method for improving the leaching rate of gallium in bauxite, comprising the following steps:

[0082] S1: providing bauxite;

[0083] S2: after the bauxite is coarsely broken, the bauxite is ball milled together with an additive and a circulating mother liquor to obtain an ore slurry;

[0084] S3: the ore slurry is subjected to pre-desilication and leaching treatment to obtain a leaching slurry;

[0085] S4: the leaching slurry is subjected to sedimentation separation to obtain a refined liquid, and the refined liquid is subjected to seed decomposition to obtain a decomposition mother liquor;

[0086] S5: ion exchange resin is added to the decomposition mother liquor to adsorb and recover gallium in the decomposition mother liquor.

[0087] The bauxite is an imported ore, and the contents of Al2O3, SiO2 and Fe2O3 are 43.38%, 2.55% and 26.97% respectively, the content of gibbsite is 58.5%, the content of bayerite is 2.0%, and the content of aluminum needle hematite is 16.5%;

[0088] The additive in step S2 is an alkaline earth metal compound, and the alkaline earth metal oxide is specifically calcium oxide; the additive is added in an amount of 5% of the mass of the bauxite; the concentration of the circulating mother liquor caustic soda is 230g / L, and the concentration of gallium in the circulating mother liquor is 0.3g / L;

[0089] The leaching treatment in step S3 is performed at a leaching temperature of 260℃ and a leaching time of 60min;

[0090] The ion exchange resin in step S5 is specifically LSC-600 ion exchange resin from Xi'an Lanxiao Science and Technology New Material Co., Ltd.

[0091] It is detected that the leaching rate of gallium in the bauxite is 74%, and the leaching rate of aluminum oxide is 92.5%.

[0092] Example 5

[0093] The embodiment provides a method for improving the dissolution rate of gallium in bauxite, which comprises the following steps:

[0094] S1: providing bauxite;

[0095] S2: coarsely crushing the bauxite and then ball milling the bauxite together with an additive and a circulating mother liquor to obtain an original ore slurry;

[0096] S3: performing pre-desilication and dissolution treatment on the original ore slurry to obtain a dissolution ore slurry;

[0097] S4: performing sedimentation separation on the dissolution ore slurry to obtain a refined liquid, and performing seed decomposition on the refined liquid to obtain a decomposition mother liquor;

[0098] S5: adding an ion exchange resin to the decomposition mother liquor to adsorb and recover gallium in the decomposition mother liquor.

[0099] In the embodiment, the bauxite is an imported bauxite, the contents of Al2O3, SiO2 and Fe2O3 are 43.38%, 2.55% and 26.97% respectively, the content of gibbsite is 58.5%, the content of bayerite is 2.0%, and the content of aluminum goethite is 16.5%.

[0100] In step S2, the additive is an alkaline earth metal compound, and the alkaline earth metal oxide is calcium oxide; the additive is added in an amount of 4% of the mass of the bauxite; the concentration of the circulating mother liquor is 230 g / L, and the concentration of gallium in the circulating mother liquor is 0.2 g / L.

[0101] In step S3, the dissolution temperature is 260 DEG C, and the dissolution time is 60 min.

[0102] In step S5, the ion exchange resin is LSC-600 ion exchange resin from Xi'an Lanxiao Science and Technology New Material Co., Ltd.

[0103] It is detected that the dissolution rate of gallium in the bauxite is 75%, and the dissolution rate of aluminum oxide is 92.8%.

[0104] Embodiment 6

[0105] The embodiment provides a method for improving the dissolution rate of gallium in bauxite, which comprises the following steps:

[0106] S1: providing bauxite;

[0107] S2: coarsely crushing the bauxite and then ball milling the bauxite together with an additive and a circulating mother liquor to obtain an original ore slurry;

[0108] S3: performing pre-desilication and dissolution treatment on the original ore slurry to obtain a dissolution ore slurry;

[0109] S4: performing sedimentation separation on the dissolution ore slurry to obtain a refined liquid, and performing seed decomposition on the refined liquid to obtain a decomposition mother liquor;

[0110] S5: adding ion exchange resin into the decomposition mother liquor to adsorb and recover gallium in the decomposition mother liquor.

[0111] The bauxite is an imported ore, and the contents of Al2O3, SiO2 and Fe2O3 are 43.38%, 2.55% and 26.97% respectively, the content of gibbsite is 58.5%, the content of bayerite is 2.0%, and the content of diaspore is 16.5%;

[0112] The additive in step S2 is an alkaline earth metal compound, and the alkaline earth metal oxide is calcium oxide; the additive is added in an amount of 3% of the mass of the bauxite; the concentration of the caustic alkali in the circulating mother liquor is 230 g / L, and the concentration of gallium in the circulating mother liquor is 0.2 g / L;

[0113] The leaching treatment in step S3 is performed at a leaching temperature of 270℃ for 60 min.

[0114] The ion exchange resin in step S5 is specifically LSC-600 ion exchange resin from Xi'an Lanxiao Science and Technology New Material Co., Ltd.

[0115] It is detected that the leaching rate of gallium in the bauxite is 82%, and the leaching rate of aluminum oxide is 93%.

[0116] Comparative Example 1

[0117] The difference between this comparative example and Example 1 is only that:

[0118] The leaching treatment in step S3 is performed at a leaching temperature of 145℃.

[0119] It is detected that the leaching rate of gallium in the bauxite is 50%, and the leaching rate of aluminum oxide is 88%.

[0120] Comparative Example 2

[0121] The difference between this comparative example and Example 1 is only that:

[0122] No additive is added in step S2.

[0123] It is detected that the leaching rate of gallium in the bauxite is 60%, and the leaching rate of aluminum oxide is 90.5%.

[0124] Comparative Example 3

[0125] The difference between this comparative example and Example 3 is only that:

[0126] The leaching treatment in step S3 is performed at a leaching temperature of 145℃.

[0127] It is detected that the leaching rate of gallium in the bauxite is 55%, and the leaching rate of aluminum oxide is 88%.

[0128] Comparative Example 4

[0129] The only difference between the present comparative example and Example 3 is that:

[0130] No additive is added in Step S2.

[0131] It is detected that the dissolution rate of gallium in the bauxite is 65%, and the dissolution rate of alumina is 90%.

[0132] Compared with Example 1, the dissolution rate of gallium in Comparative Example 1 and Comparative Example 2 is significantly reduced; compared with Example 3, the dissolution rate of gallium in Comparative Example 3 and Comparative Example 4 is significantly reduced; this shows that the appropriate dissolution temperature and the additive both have a great contribution to the dissolution of gallium.

[0133] Example 1 and Example 4 use different bauxites, and compared with Comparative Example 1 and Comparative Example 3 which use the same bauxite, the dissolution rate of gallium is significantly increased, and the dissolution rate of alumina is increased to a certain extent, which shows that the technical solution of the present disclosure by controlling the dissolution temperature to be above 260℃ and using at least one of the oxides of calcium, the hydroxides of calcium, the oxides of magnesium and the hydroxides of magnesium as the additive has good adaptability to different bauxites.

[0134] The bauxite dissolution method for improving the gallium leaching rate according to some embodiments of the present disclosure has the following advantages compared with the related art:

[0135] The bauxite dissolution method for improving the gallium leaching rate according to some embodiments of the present disclosure, by adding an additive in the ball milling process, the additive including at least one of the oxides of calcium, the hydroxides of calcium, the oxides of magnesium and the hydroxides of magnesium, can not only convert the goethite in the bauxite into hematite and make the silicon minerals react to generate hydrous garnet, thereby promoting the dissolution of the gallium associated in the goethite and the silicon minerals, but also can reduce the consumption.

[0136] Various embodiments of the present disclosure can exist in the form of a range; it should be understood that the description in the form of a range is only for the convenience and brevity, and should not be understood as a hard limit on the scope of the present disclosure; therefore, it should be considered that the described range has specifically disclosed all possible sub-ranges and single values within the range. For example, it should be considered that the range description from 1 to 6 has specifically disclosed sub-ranges, such as from 1 to 3, from 1 to 4, from 1 to 5, from 2 to 4, from 2 to 6, from 3 to 6, etc., as well as single numbers within the range, such as 1, 2, 3, 4, 5 and 6, regardless of the range. In addition, whenever a numerical range is indicated in this document, it refers to any cited number (fraction or integer) within the indicated range.

[0137] In the present disclosure, the orientation words such as "upper" and "lower" are specifically the directions of the drawing surface in the drawings unless otherwise stated. In addition, in the description of the present disclosure, the terms "comprise", "contain" and the like mean "including but not limited to". Moreover, the terms "comprise", "contain" or any other variant thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements not only includes those elements, but also includes other elements not explicitly listed or inherent to such a process, method, article or device. Without more limitations, the elements defined by the statement "comprise" do not exclude the presence of other identical elements in the process, method, article or device including the elements. In this paper, the relationship terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between the entities or operations. In this paper, the "and / or" describes the association relationship of the associated objects, which means that there can be three relationships, for example, A and / or B can represent the following cases: A exists alone, A and B exist together, and B exists alone. For the association relationship of more than three associated objects described by "and / or", it means that any one of the three associated objects can exist alone, or any at least two of them exist together, for example, for A, and / or B, and / or C, it means that any one of A, B and C exists alone, or any two of them exist together, or all three of them exist together. In this paper, "at least one" means one or more, and "multiple" means two or more. "At least one", "at least one of the following" or similar expressions mean any combination of these items, including any combination of single or multiple items. For example, "at least one of a, b, or c", or "at least one of a, b, and c", can mean a, b, c, a-b (i.e. a and b), a-c, b-c, or a-b-c, where a, b, and c can be single or multiple.

[0138] The above description is only a specific embodiment of the present disclosure, which enables those skilled in the art to understand or implement the present disclosure. Various modifications of these embodiments will be apparent to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present disclosure. Therefore, the present disclosure will not be limited to these embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for improving gallium leaching rate in bauxite leaching, comprising the following steps: Provide bauxite, wherein the bauxite has a goethite content of more than 10%; The bauxite is coarsely crushed and then ball-milled with additives and circulating mother liquor to obtain raw ore slurry. The raw ore slurry is subjected to pre-desiliconization and leaching treatment to obtain leached ore slurry; The dissolved slurry is subjected to sedimentation separation to obtain a concentrate, and the concentrate is subjected to seed crystal decomposition to obtain a decomposition mother liquor; An ion exchange resin is added to the decomposition mother liquor to adsorb and recover gallium from the mother liquor. The additives include alkaline earth metal compounds, which include at least one of calcium oxide, calcium hydroxide, magnesium oxide, and magnesium hydroxide, and the leaching treatment temperature is above 260°C.

2. The bauxite leaching method for improving gallium leaching rate according to claim 1, wherein, The amount of the additive added is 2% to 6% of the mass of the bauxite.

3. The bauxite leaching method for improving gallium leaching rate according to claim 1, wherein, The concentration of caustic alkali in the circulating mother liquor is above 200 g / L.

4. The bauxite leaching method for improving gallium leaching rate according to claim 1, wherein, The concentration of caustic alkali in the circulating mother liquor is 200 g / L to 300 g / L.

5. The bauxite leaching method for improving gallium leaching rate according to claim 1, wherein, The concentration of gallium in the circulating mother liquor is no higher than 0.3 g / L.

6. The bauxite leaching method for improving gallium leaching rate according to claim 1, wherein, The leaching temperature for the leaching treatment is 260℃~280℃.

7. The bauxite leaching method for improving gallium leaching rate according to claim 1, wherein, The dissolution time for the dissolution treatment is 60 minutes or more.

8. The bauxite leaching method for improving gallium leaching rate according to claim 1, wherein, The bauxite includes at least one of gibbsite-type bauxite and gibbsite-monohydrate mixed bauxite.

9. The bauxite leaching method for improving gallium leaching rate according to claim 1, wherein, The pre-desiliconization includes the following steps: stirring the raw ore slurry at 80-105°C for 6-10 hours.

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