Method for producing lithium carbonate for cathode material of lithium ion battery from bauxite

Abstract

The invention relates to a method for producing lithium carbonate (Li2CO3) from bauxite for the cathode material of lithium ion batteries by removing lithium having a negative effect from the process in a plant for the production of aluminum hydroxide (Al (OH) 3) using bauxite. The lithium can be recycled to be used as a cathode material of a rechargeable lithium ion battery of a portable computer, a tablet personal computer, a smart phone and an electric automobile.

Description

Technical Field

[0001] The present invention relates to a method for removing lithium, which has a negative impact, from a facility for the production of aluminum hydroxide (AI(OH)3) using bauxite, thereby enabling lithium recovery for use in cathode materials for rechargeable lithium-ion batteries for laptops, tablets, smartphones and electric vehicles.

[0002] - Dissolve the lithium (300-350ppm) in the bauxite ore under high temperature and pressure of 250℃-280℃ in an alkaline environment and enter the sodium aluminate solution;

[0003] - by adding the sodium aluminate solution and aluminum hydroxide to which lithium (25-30 ppm) is added in a precipitation tank, and precipitating lithium aluminum carbonate hydroxide (Li2AI4(CO3)(OH)12.3H2O);

[0004] —After the precipitated lithium aluminum carbonate hydroxide hydrate (Li2AI4(CO3)(OH)12.3H2O) structure is filtered through a filter press, the lithium-free solution is placed in a lithium-free solution tank, and the solid lithium cake is placed in a lithium cake bin;

[0005] - Send the lithium cake containing 2-2.5% lithium in the lithium cake bin to the cake preparation tank and mix it with water;

[0006] —The resulting mixture is sent to a reactor where the lithium is converted into a liquid phase at high temperature and pressure;

[0007] - Pressing and filtration process for liquid / solid separation after the reactor;

[0008] - the boehmite solid obtained in the filtration stage is sent to the process in the facility to obtain aluminum hydroxide;

[0009] — During the filtration stage, the liquid product containing 1000-1200 ppm lithium was detected and sent to the evaporator;

[0010] - Evaporating the lithium-containing liquid solution through an evaporator, filtering and drying again to obtain lithium carbonate with a purity of about 100%;

[0011] A method for producing lithium carbonate (Li2CO3) from bauxite is carried out in steps.

[0012] Li2AI4(CO3)(OH)12.3H2O+H2O→4AIOOH+Li2CO3+8H2O

[0013] Prior Art

[0014] Today, rechargeable lithium-ion batteries are used to power laptops, tablets, smartphones and electric vehicles.

[0015] Lithium carbonate (Li2CO3) used in lithium-ion batteries is commercially produced from minerals and lake water. In the production of lithium carbonate Li2CO3, lithium-containing lake water is brought into a pond, evaporated using solar energy, and calcium chloride CaCl2 is added to the solution with increased lithium concentration, and sulfate ions are precipitated as gypsum. Sodium chloride (NaCl), potassium chloride (KCl) and magnesium chloride (MgCl2) in the environment are precipitated and separated in the form of sulfates.

[0016] In this solution with a lithium content of 4-6%, boron and magnesium are precipitated from the solution by adding lime and soda ash to the environment, and then lithium carbonate (Li2CO3) is crystallized from the solution.

[0017] When producing lithium carbonate (Li2CO3) from minerals, the extraction method of sulfuric acid (H2SO4) and sodium carbonate (Na2CO3) is used. First, α-spodumene is converted into β-spodumene by calcination. After β-spodumene is acid-roasted at 200°C, lithium sulfate (Li2SO4) is brought into water. By adding sodium carbonate (Na2CO3) and increasing the temperature, lithium carbonate (Li2CO3) is crystallized.

[0018] 2.LiAISi2O6+H2SO4 H2O+AI2O3 5+4SiO2+Li2SO4

[0019] The extraction of sodium carbonate (Na2CO3) is carried out in an autoclave at a temperature of 215°C and a pressure of 20 bar. CO2 is released into the environment and the insoluble lithium carbonate (Li2CO3) is converted into lithium bicarbonate (LiHCO3). The heated lithium carbonate (Li2CO3) crystallizes.

[0020] As technology develops, the use of lithium batteries increases, and the demand for lithium carbonate (Li2CO3) raw materials also increases. Limited lithium reserves change the supply and demand balance, thereby increasing the need for new lithium resources. It is more expensive to obtain lithium carbonate (Li2CO3) from minerals than from lakes. The production of lithium carbonate (Li2CO3) from lithium minerals requires high-temperature calcination. This results in the production method of lithium carbonate (Li2CO3) being a high-energy cost process.

[0021] Therefore, due to the negative situations encountered in the prior art and in the situations described above, it is necessary to make developments in the relevant technical field.

[0022] Purpose of the invention

[0023] Since there are negative aspects in the prior art, the present invention aims to solve all the negative aspects mentioned.

[0024] The object of the present invention is to provide a facility for the production of aluminum hydroxide (AI(OH)3) using bauxite, which enables the recovery of lithium for cathode materials for rechargeable lithium-ion batteries for laptops, tablets, smartphones and electric vehicles by removing lithium from the process which has a negative impact,

[0025] - Dissolve the lithium (300-350ppm) in the bauxite ore under high temperature and pressure of 250℃-280℃ in an alkaline environment and enter the sodium aluminate solution;

[0026] - by adding the sodium aluminate solution and aluminum hydroxide to which lithium (25-30 ppm) is added in a precipitation tank, and precipitating lithium aluminum carbonate hydroxide (Li2AI4(CO3)(OH)12.3H2O);

[0027] —After the precipitated lithium aluminum carbonate hydroxide hydrate (Li2AI4(CO3)(OH)12.3H2O) structure is filtered through a filter press and a filter, the lithium-free solution is placed in a lithium-free solution tank, and the powdered lithium cake is placed in a lithium cake bin;

[0028] - Send the lithium cake containing 2-2.5% lithium in the lithium cake bin to the cake preparation tank and mix it with water;

[0029] —The resulting mixture is sent to a reactor where the lithium is converted into a liquid phase at high temperature and pressure;

[0030] - Pressing and filtration process for liquid / solid separation after the reactor;

[0031] - the boehmite solid obtained in the filtration stage is sent to the process in the facility to obtain aluminum hydroxide;

[0032] — During the filtration stage, the liquid product containing 1000-1200 ppm lithium was detected and sent to the evaporator;

[0033] - Evaporating the lithium-containing liquid solution through an evaporator, filtering it again and drying it to obtain lithium carbonate with a purity of about 99.6%;

[0034] A method for producing lithium carbonate (Li2CO3) from bauxite is carried out in steps.

[0035] The purpose of the present invention is to ensure that the lithium carbonate obtained by the method can be used as a raw material for producing other lithium compounds in the glass, ceramic, glaze and enamel industries in addition to being used for producing lithium ion batteries.

[0036] Due to the method of the present invention;

[0037] - the production process of lithium carbonate (Li2CO3) using bauxite, thereby making bauxite a new source of raw materials for the preparation of lithium compounds,

[0038] —Lithium reserves increase with the use of bauxite,

[0039] - provides low-cost lithium production compared to prior art,

[0040] - By removing lithium from the process of extracting lithium from bauxite, the negative impact of lithium on the process is eliminated,

[0041] - Obtain high-purity products that can be used in lithium batteries,

[0042] —Provide a structure consisting of equipment that is technically easy to install and operate and does not impose a burden on the enterprise. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1 Schematic diagram of the apparatus used in the process for producing lithium carbonate (Li2CO3) from bauxite.

[0044] Figure 2 This is a mineralogical structural analysis diagram of the cake precipitated from the sodium aluminate solution by adding aluminum hydroxide, measured by XRD (GNR-Explorer) diffractometer.

[0045] Figure 3 It is a mineralogical structure analysis diagram of lithium carbonate (Li2CO3), a product produced by a method of producing lithium carbonate (Li2CO3) from bauxite, measured by an XRD (GNR-Explorer) diffractometer.

[0046] Reference Number:

[0047] 1. Sedimentation tank

[0048] 2. Filters

[0049] 3. No lithium solution tank

[0050] 4. Lithium cake warehouse

[0051] 5. Cake preparation tank

[0052] 6. Reactor

[0053] 7. Evaporator DETAILED DESCRIPTION OF THE INVENTION

[0055] Today, rechargeable lithium-ion batteries are used to power laptops, tablets, smartphones and electric vehicles.

[0056] In the production of lithium-ion batteries, lithium carbonate (Li2CO3) is required as a cathode material.

[0057] Currently, lithium carbonate (Li2CO3) is produced from minerals and lake water by a developed process. Since the process for producing lithium carbonate (Li2CO3) is expensive, the method of producing lithium carbonate (Li2CO3) from bauxite of the present invention was developed.

[0058] Li2AI4(CO3)(OH)12.3H2O+H2O→4AIOOH+Li2CO3+8H2O

[0059] Figure 1 The present invention is a schematic diagram of an apparatus used in a method for producing lithium carbonate (Li2CO3) from bauxite, wherein the apparatus is used in a facility for producing aluminum hydroxide (Al(OH)3) from bauxite.

[0060] In the facility for producing aluminum hydroxide (AI(OH)3) using bauxite of the present invention, in the implementation process of the method for removing lithium with negative effects from the process so that lithium recovery can be used for cathode materials of rechargeable lithium-ion batteries for portable computers, tablets, smart phones and electric vehicles, first, lithium (300-350ppm) in bauxite ore is dissolved under high temperature and pressure of 250°C-280°C in an alkaline environment and enters a sodium aluminate solution.

[0061] like Figure 1 As shown, the sodium aluminate solution and aluminum hydroxide with lithium (25-30 ppm) added are added to a precipitation tank (1) to precipitate lithium aluminum carbonate hydroxide hydrate (Li2AI4(CO3)(OH)12.3H2O). After the precipitated lithium aluminum carbonate hydroxide hydrate (Li2AI4(CO3)(OH)12.3H2O) structure is pressed and filtered through a filter (2), the lithium-free solution is placed in a lithium-free solution tank (3), and the powdered lithium cake is placed in a lithium cake bin (4).

[0062] The lithium in the sodium aluminate solution reacts with aluminum hydroxide to form a lithium aluminum carbonate hydroxide hydrate (Li2Al4(CO3(OH)12.3H2O) structure and precipitate. Figure 2 (Analysis diagram showing the mineralogical structure from the XRD (GNR-Explorer) diffractometer.)

[0063] The lithium cake containing 2-2.5% lithium in the lithium cake bin (4) is sent to the cake preparation tank (5) to be mixed with water. The obtained mixture is sent to the reactor (6), where the lithium is converted into a liquid phase under high temperature and pressure. After the reaction is achieved in the reactor (6), a pressing and filtering (2) process for liquid / solid separation is carried out. The boehmite structure solid obtained in the filtering (2) stage is sent to the process flow in the facility to obtain aluminum hydroxide, and the liquid phase solution containing 1000-1200 ppm lithium is detected and sent to the evaporator (7).

[0064] The lithium-containing liquid solution is evaporated by an evaporator (7), filtered again (2) and dried to obtain lithium carbonate (Li2CO3) with a purity of about 100%.

[0065] The resulting lithium carbonate (Li2CO3) was found to be;

[0066] —Analysis by XRD (GNR-Explorer) diffractometer shows that it is 100% lithium carbonate (Li2CO3)

[0067] ( Figure 3 ),

[0068] —Having the purity of lithium carbonate (Li2CO3) raw material for lithium-ion battery cathode material.

[0069] The lithium carbonate obtained by the method of the present invention can be used as a raw material for producing other lithium compounds in the glass, ceramic, glaze and enamel industries in addition to being used for producing lithium ion batteries.

[0070] Due to the method of the present invention;

[0071] - the production process of lithium carbonate (Li2CO3) using bauxite, thereby making bauxite a new source of raw materials for the preparation of lithium compounds,

[0072] —Lithium reserves increase with the use of bauxite,

[0073] - provides low-cost lithium production compared to prior art,

[0074] - By removing lithium from the process of extracting lithium from bauxite, the negative impact of lithium on the process is eliminated,

[0075] - Obtain high-purity products that can be used in lithium batteries,

[0076] —Provide a structure consisting of equipment that is technically easy to install and operate and does not impose a burden on the enterprise.

Claims

1. The invention is a method for recovering lithium for use as cathode material in rechargeable lithium-ion batteries for laptops, tablets, smartphones and electric vehicles by removing lithium from the process, in a facility for the production of aluminum hydroxide (AI(OH)3) using bauxite, characterized in that: include: - Dissolve the lithium (300-350ppm) in the bauxite ore under high temperature and pressure of 250℃-280℃ in an alkaline environment and enter the sodium aluminate solution; - by adding the sodium aluminate solution and aluminum hydroxide to which lithium (25-30 ppm) is added in a precipitation tank, and precipitating lithium aluminum carbonate hydroxide (Li2Al4(CO3)(OH)12.3H2O); —The precipitated lithium aluminum carbonate hydroxide hydrate (Li2Al4(CO3)(OH)12.3H2O) structure is filtered through a filter press and a filter, and the lithium-free solution is placed in a lithium-free solution tank, Put the solid lithium cake into the lithium cake bin; - Send the lithium cake containing 2-2.5% lithium in the lithium cake bin to the cake preparation tank and mix it with water; —The resulting mixture is sent to a reactor where the lithium is converted into a liquid phase at high temperature and pressure; - Pressing and filtration process for liquid / solid separation after the reactor; - the boehmite solid obtained in the filtration stage is sent to the process in the facility to obtain aluminum hydroxide; — During the filtration stage, the liquid product containing 1000-1200 ppm lithium was detected and sent to the evaporator; - Evaporating the lithium-containing liquid solution through an evaporator, filtering and drying again to obtain lithium carbonate with a purity of about 100%; A method for producing lithium carbonate (Li2CO3) from bauxite is carried out in steps.

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