Method for selectively extracting lithium from sedimentary lithium ore through solid-phase reaction

Abstract

The invention relates to the field of sedimentary lithium ore smelting, in particular to a method for selectively extracting lithium from sedimentary lithium ore through a solid-phase reaction. The method comprises the following steps that 1, sedimentary lithium ore is crushed and sieved, and sedimentary lithium ore fine particles are obtained; step 2, mixing the sedimentary lithium ore fine particle material with causticized mud, and carrying out ball milling; obtaining a mixture; step 3, mixing the mixture with water to prepare slurry, and performing ultrasonic treatment and solid-liquid separation to obtain a lithium leaching solution; the sedimentary lithium ore is carbonate clay type lithium ore, and the grade of Li2O is lower than 0.6%; the carbonate clay type lithium ore contains montmorillonite group minerals. The method provided by the invention is simple, is easy for large-scale industrial application, has a good extraction effect on lithium in specific types of low-grade sedimentary lithium ores (carbonate clay type lithium ores), and has important practical application significance.

Description

Technical Field

[0001] The invention relates to the field of sedimentary lithium ore smelting, and in particular to a method for selectively extracting lithium from sedimentary lithium ore by utilizing solid phase reaction. Background Art

[0002] Lithium (Li), as an important clean energy metal, plays an important role in the fields of electric vehicles and energy storage systems. Natural lithium resources can generally be divided into three categories: salt lake brine type, hard rock type and clay type. At present, the most mined and utilized lithium mines in the world are salt lake brine type lithium mines and hard rock type lithium mines. Clay type lithium mines are a low-grade sedimentary lithium mine that was discovered relatively late and has not yet been developed and utilized on a large scale. However, the existing distribution pattern of lithium resources and actual demand have made this type of lithium mine highly valued.

[0003] However, clay-type lithium ore is characterized by low lithium grade and complex composition. Lithium recovery is mostly achieved through acid leaching or auxiliary agent roasting, without targeted treatment based on the properties of the minerals, resulting in low lithium recovery rate and high energy consumption.

[0004] How to efficiently achieve the selective leaching of lithium from clay-type lithium ore (low-grade sedimentary lithium ore) is a technical problem that technicians in this field have been working hard to solve. Summary of the invention

[0005] Based on the above content, the present invention provides a method for selectively extracting lithium from sedimentary lithium ore using solid phase reaction. The method of the present invention can achieve selective leaching of lithium from sedimentary lithium ore without high energy consumption operations such as roasting, and has the advantages of high lithium extraction rate and low impurity element extraction rate.

[0006] To achieve the above object, the present invention provides the following solutions:

[0007] The present invention provides a method for selectively extracting lithium from a sedimentary lithium ore by using a solid phase reaction, comprising the following steps:

[0008] Step 1, crushing and sieving the sedimentary lithium ore to obtain sedimentary lithium ore fine particles;

[0009] Step 2, mixing the sedimentary lithium ore fine particles with causticized mud and performing ball milling to obtain a mixture;

[0010] Step 3, mixing the mixture with water to form a slurry and subjecting it to ultrasonic treatment to solid-liquid separation to obtain a lithium leaching solution and lithium extraction slag;

[0011] The sedimentary lithium ore is a carbonate clay type lithium ore, wherein the Li2O grade is lower than 0.6%; the carbonate clay type lithium ore contains montmorillonite minerals.

[0012] In a preferred embodiment of the present invention, the screening is specifically through a 20-mesh sieve.

[0013] In a preferred embodiment of the present invention, the mass ratio of the sedimentary lithium ore fine particles to the causticized mud is 100:(10-20).

[0014] In a preferred embodiment of the present invention, the rotation speed of the ball mill is 200-300 rpm; and the time of the ball mill is 0.5-2 h.

[0015] In a preferred embodiment of the present invention, the ball milling medium is steel balls, and the material-ball ratio is 1:10.

[0016] In a preferred embodiment of the present invention, the mass ratio of the mixed material to the water is 1:(10-20).

[0017] In a preferred embodiment of the present invention, the pH of the slurry is 2-5.

[0018] In a preferred embodiment of the present invention, the pH of the slurry is adjusted to 2-5 by adding an inorganic acid such as sulfuric acid to the slurry.

[0019] In a preferred embodiment of the present invention, the ultrasonic wave intensity of the ultrasonic treatment is 3.0 W / cm 3 , time is 0.5-2h.

[0020] The present invention discloses the following technical effects:

[0021] The present invention provides an efficient method for selectively extracting lithium from carbonate clay-type lithium ore in sedimentary lithium ore. Carbonate clay-type lithium ore contains silica-alumina clay minerals, namely montmorillonite minerals, which have a layered structure composed of silicon-oxygen tetrahedrons and aluminum-oxygen octahedrons. Lithium mainly exists between the layers, which belongs to a special adsorption state. By mixing carbonate clay-type lithium ore with causticized mud and ball milling (solid phase reaction), the cations (mainly Ca in the causticized mud) can be removed. 2+ ) migrate to the interlayers of montmorillonite minerals, and at the same time, the adsorbed lithium ions migrate out from the interlayers. In addition, ball milling can break and peel off the layered structure in the carbonate clay-type lithium ore, thereby promoting the migration of lithium ions. The ball-milled mixture is then placed in water for ultrasonic treatment to further accelerate the dissolution of lithium in water, thereby achieving efficient dissolution of lithium from sedimentary lithium ore (carbonate clay-type lithium ore).

[0022] The method of the invention is simple, easy to be applied in large-scale industrialization, has good effect on extracting lithium from specific types of low-grade sedimentary lithium ore (carbonate clay type lithium ore), and has important practical application significance. DETAILED DESCRIPTION

[0023] Various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as limiting the present invention, but should be understood as a more detailed description of certain aspects, features, and embodiments of the present invention.

[0024] It should be understood that the terms described in the present invention are only for describing a particular embodiment and are not intended to limit the present invention. In addition, for the numerical range in the present invention, it should be understood that each intermediate value between the upper and lower limits of the scope is also specifically disclosed. The intermediate value in any stated value or stated range, and each smaller range between any other stated value or intermediate value in the described range is also included in the present invention. The upper and lower limits of these smaller ranges can be independently included or excluded in the scope.

[0025] Unless otherwise indicated, all technical and scientific terms used herein have the same meanings as those generally understood by those skilled in the art. Although the present invention describes only preferred methods and materials, any methods and materials similar or equivalent to those described herein may also be used in the implementation or testing of the present invention. All documents mentioned in this specification are incorporated by reference to disclose and describe the methods and / or materials associated with the documents. In the event of a conflict with any incorporated document, the content of this specification shall prevail.

[0026] It will be apparent to those skilled in the art that various modifications and variations may be made to the specific embodiments of the present invention description without departing from the scope or spirit of the present invention. Other embodiments derived from the present invention description will be apparent to the skilled artisan. The present invention description and examples are exemplary only.

[0027] The words “include,” “including,” “have,” “contain,” etc. used in this document are open-ended terms, meaning including but not limited to.

[0028] The embodiment of the present invention provides a method for selectively extracting lithium from a sedimentary lithium ore by using a solid phase reaction, comprising the following steps:

[0029] Step 1, crushing the sedimentary lithium ore (Li2O grade 0.48%), passing through a 20-mesh sieve, and obtaining sedimentary lithium ore fine particles;

[0030] Step 2, mixing the sedimentary lithium ore fine particles with the causticized mud in a mass ratio of 100:(10-20) and ball milling; the ball milling speed is 200-300rpm, the ball milling time is 0.5-2h, the ball milling medium is steel balls, and the material-ball ratio is 1:10; after the ball milling is completed, a mixture is obtained;

[0031] Step 3: The mixture is mixed with water in a mass ratio of 1:(10-20) to prepare a slurry and subjected to ultrasonic treatment. The pH of the slurry is adjusted to 2-5 by adding sulfuric acid to the slurry. The ultrasonic intensity of the ultrasonic treatment is 3.0 W / cm 3 , the time is 0.5-2h; then the solid and liquid are separated to obtain lithium leaching solution and lithium extraction slag. The lithium extraction slag can be used as a building material in the construction industry to improve the comprehensive utilization rate of sedimentary lithium ore.

[0032] The technical solutions described in the present invention, unless otherwise specified, are all conventional solutions in the art, and the reagents or raw materials used, unless otherwise specified, are purchased from commercial channels or have been disclosed.

[0033] The low-grade sedimentary lithium ore used in the embodiment of the present invention comes from southwest China, with a Li2O grade of 0.48%, and contains silica-alumina clay minerals, namely montmorillonite minerals, and lithium mainly exists between the montmorillonite mineral layers.

[0034] The causticized mud used in the embodiments of the present invention is a byproduct produced in the causticizing stage during the alkali recovery process of Xining Chengbeiqing Paper Mill, and its main component is calcium carbonate.

[0035] The technical solutions provided by the present invention are described in detail below in conjunction with the embodiments, but they should not be construed as limiting the protection scope of the present invention.

[0036] Example 1

[0037] A method for selectively extracting lithium from a sedimentary lithium ore using a solid phase reaction, the steps are as follows:

[0038] Step 1, crushing the sedimentary lithium ore, passing it through a 20-mesh sieve, and obtaining a sedimentary lithium ore fine particle material;

[0039] Step 2, mixing the sedimentary lithium ore fine particles with the causticized mud in a mass ratio of 100:15 and ball milling; the ball milling speed is 300 rpm, the ball milling time is 1.5 hours, the ball milling medium is steel balls, and the material-to-ball ratio is 1:10; after the ball milling is completed, a mixture is obtained;

[0040] Step 3: The mixture is mixed with water in a mass ratio of 1:15 to prepare a slurry and subjected to ultrasonic treatment. The pH of the slurry is adjusted to 3 (the pH can be 2-5) by adding sulfuric acid to the slurry. The ultrasonic intensity of the ultrasonic treatment is 3.0 W / cm 3 , time is 1.5h; then the solid and liquid are separated to obtain lithium leaching solution and lithium extraction slag.

[0041] In this embodiment, the Li extraction rate is 98.1%, the impurity element silicon extraction rate is 0.9%, and the Al extraction rate is 0.8%.

[0042] Example 2

[0043] A method for selectively extracting lithium from a sedimentary lithium ore using a solid phase reaction, the steps are as follows:

[0044] Step 1, crushing the sedimentary lithium ore, passing it through a 20-mesh sieve, and obtaining a sedimentary lithium ore fine particle material;

[0045] Step 2, mixing the sedimentary lithium ore fine particles with the causticized mud in a mass ratio of 100:10 and ball milling; the ball milling speed is 300 rpm, the ball milling time is 1 hour, the ball milling medium is steel balls, and the material-to-ball ratio is 1:10; after the ball milling is completed, a mixture is obtained;

[0046] Step 3: The mixture is mixed with water in a mass ratio of 1:15 to prepare a slurry and subjected to ultrasonic treatment. The pH of the slurry is adjusted to 3 (the pH can be 2-5) by adding sulfuric acid to the slurry. The ultrasonic intensity of the ultrasonic treatment is 3.0 W / cm 3 , time is 1h; then the solid and liquid are separated to obtain lithium leaching solution and lithium extraction slag.

[0047] In this embodiment, the Li extraction rate is 94.7%, the impurity element silicon extraction rate is 0.8%, and the Al extraction rate is 0.6%.

[0048] Example 3

[0049] A method for selectively extracting lithium from a sedimentary lithium ore using a solid phase reaction, the steps are as follows:

[0050] Step 1, crushing the sedimentary lithium ore, passing it through a 20-mesh sieve, and obtaining a sedimentary lithium ore fine particle material;

[0051] Step 2, mixing the sedimentary lithium ore fine particles with the causticized mud in a mass ratio of 100:20 and ball milling; the ball milling speed is 300 rpm, the ball milling time is 2 hours, the ball milling medium is steel balls, and the material-ball ratio is 1:10; after the ball milling is completed, a mixture is obtained;

[0052] Step 3: The mixture is mixed with water in a mass ratio of 1:20 to prepare a slurry and subjected to ultrasonic treatment. The pH of the slurry is adjusted to 3 (the pH can be 2-5) by adding sulfuric acid to the slurry. The ultrasonic intensity of the ultrasonic treatment is 3.0 W / cm 3 , time is 2h; then the solid and liquid are separated to obtain lithium leaching solution and lithium extraction slag.

[0053] In this embodiment, the Li extraction rate is 98.4%, the impurity element silicon extraction rate is 1.1%, and the Al extraction rate is 0.9%.

[0054] Example 4

[0055] A method for selectively extracting lithium from a sedimentary lithium ore using a solid phase reaction, the steps are as follows:

[0056] Step 1, crushing the sedimentary lithium ore, passing it through a 20-mesh sieve, and obtaining a sedimentary lithium ore fine particle material;

[0057] Step 2, mixing the sedimentary lithium ore fine particles and the causticized mud in a mass ratio of 100:15 and ball milling; the ball milling speed is 300 rpm, the ball milling time is 2 hours, the ball milling medium is steel balls, and the material-to-ball ratio is 1:10; after the ball milling is completed, a mixture is obtained;

[0058] Step 3: The mixture is mixed with water in a mass ratio of 1:15 to prepare a slurry and subjected to ultrasonic treatment. The pH of the slurry is adjusted to 3 (the pH can be 2-5) by adding sulfuric acid to the slurry. The ultrasonic intensity of the ultrasonic treatment is 3.0 W / cm 3 , time is 2h; then the solid and liquid are separated to obtain lithium leaching solution and lithium extraction slag.

[0059] In this embodiment, the Li extraction rate is 96.8%, the impurity element silicon extraction rate is 1.2%, and the Al extraction rate is 1.0%.

[0060] Comparative Example 1

[0061] A method for selectively extracting lithium from a sedimentary lithium ore using a solid phase reaction, the steps are as follows:

[0062] Step 1, crushing the sedimentary lithium ore, passing it through a 20-mesh sieve, and obtaining a sedimentary lithium ore fine particle material;

[0063] Step 2, mixing the sedimentary lithium ore fine particles with calcium carbonate in a mass ratio of 100:15 and ball milling; the ball milling speed is 300 rpm, the ball milling time is 1.5 hours, the ball milling medium is steel balls, and the material-to-ball ratio is 1:10; after the ball milling is completed, a mixture is obtained;

[0064] Step 3: The mixture is mixed with water in a mass ratio of 1:15 to prepare a slurry and subjected to ultrasonic treatment. The pH of the slurry is adjusted to 3 (the pH can be 2-5) by adding sulfuric acid to the slurry. The ultrasonic intensity of the ultrasonic treatment is 3.0 W / cm 3 , time is 1.5h; then solid-liquid separation is carried out to obtain lithium leaching solution and lithium extraction slag (that is, the only difference from Example 1 is that the causticized mud is replaced by calcium carbonate; the other steps and parameters are the same as Example 1).

[0065] In this comparative example, the Li extraction rate is 86.5%, the impurity element silicon extraction rate is 1.5%, and the Al extraction rate is 1.2%.

[0066] By comparing Comparative Example 1 and Example 1, it can be seen that the lithium extraction rate is significantly reduced by replacing the causticized mud with calcium carbonate. This may be because other components in the causticized mud besides calcium carbonate have a certain promoting effect on the extraction of lithium, which needs further study.

[0067] The embodiments described above are only descriptions of the preferred modes of the present invention, and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should all fall within the protection scope determined by the claims of the present invention.

Claims

1. A method for selectively extracting lithium from sedimentary lithium ore using solid phase reaction, characterized in that: The following steps are involved: Step 1, crushing and sieving the sedimentary lithium ore to obtain sedimentary lithium ore fine particles; Step 2, mixing the sedimentary lithium ore fine particles with causticized mud and performing ball milling to obtain a mixture; Step 3, mixing the mixture with water to form a slurry and subjecting it to ultrasonic treatment to solid-liquid separation to obtain a lithium leaching solution; The sedimentary lithium ore is a carbonate clay type lithium ore, wherein the Li2O grade is lower than 0.6%; the carbonate clay type lithium ore contains montmorillonite minerals.

2. The method for selectively extracting lithium from sedimentary lithium ore by solid phase reaction according to claim 1, characterized in that: The sieving is specifically through a 20-mesh sieve.

3. The method for selectively extracting lithium from sedimentary lithium ore by solid phase reaction according to claim 1, characterized in that: The mass ratio of the sedimentary lithium ore fine particles to the causticized mud is 100:(10-20).

4. The method for selectively extracting lithium from sedimentary lithium ore by solid phase reaction according to claim 1, characterized in that: The rotation speed of the ball mill is 200-300 rpm; the time of the ball mill is 0.5-2 h.

5. The method for selectively extracting lithium from sedimentary lithium ore by solid phase reaction according to claim 1, characterized in that: The mass ratio of the mixed material to the water is 1:(10-20).

6. The method for selectively extracting lithium from sedimentary lithium ore by solid phase reaction according to claim 1, characterized in that: The pH of the slurry is 2-5.

7. The method for selectively extracting lithium from sedimentary lithium ore by solid phase reaction according to claim 1, characterized in that: The ultrasonic wave intensity of the ultrasonic treatment is 3.0 W / cm 3 , time is 0.5-2h.