CN108384955A - A method of from selectively carrying lithium in waste material containing lithium battery - Google Patents

Abstract

The invention provides a method for selectively extracting lithium from lithium-containing battery waste. The method comprises the following steps: (1) mixing the pretreated lithium-containing battery waste with an aqueous oxide solution, performing a leaching reaction on the obtained raw material slurry, and obtaining the leaching slurry after the reaction; (2) adjusting step (1) The pH of the leaching slurry is to 7-13, and the obtained reaction slurry is subjected to solid-liquid separation to obtain a solid slag and a lithium-containing purification solution; (3) adding carbonic acid to the lithium-containing purification solution described in step (2) salt, carry out lithium precipitation reaction, after the reaction, solid-liquid separation obtains lithium carbonate product and lithium precipitation tail liquid, and described lithium precipitation tail liquid is returned in the leaching reaction system of step (1) after being adjusted to acidity. The method provided by the invention has wide applicability, short flow process, simple and convenient operation, mild reaction conditions, low cost of reaction raw materials, no discharge of three wastes in the whole process, and realizes highly selective recovery of lithium resources in lithium-containing battery waste.

Description

A method for selectively extracting lithium from lithium-containing battery waste

technical field

The invention relates to the technical field of recycling lithium resources from lithium-ion battery waste, in particular to a method for selectively extracting lithium from lithium-containing battery waste.

Background technique

Lithium-ion batteries are widely used in 3C digital products such as mobile phones, notebook computers, digital cameras, electric vehicles, and energy storage due to their advantages such as high energy, light weight, long cycle life, and no memory effect. In 2011 alone, the production of lithium-ion batteries in my country was as high as 2.9 billion. Accompanied by it, the generation of a large number of waste lithium-ion batteries has posed a severe challenge to the electronic waste disposal and environmental protection in my country and the world. On the one hand, waste lithium-ion batteries contain toxic and flammable electrolytes, heavy metals and other harmful components. Lithium, cobalt, nickel, manganese, copper, aluminum and other metal resources, if they can be efficiently recovered, not only have considerable economic value, but also can largely alleviate my country's current shortage of cobalt, lithium and other resources.

At present, driven by economic interests, the focus of recycling waste lithium-ion batteries is the efficient recovery of valuable metal elements in electrode materials. Usually, waste batteries are discharged and disassembled, mechanically crushed, screened and separated to obtain electrode active material powder, the powder is acid leached to obtain leachate, and then acid adjustment, filtration, lithium precipitation, washing, drying and other processes are finally obtained to obtain carbonic acid Precursor materials for lithium products and corresponding electrode materials. The technical principle of the above-mentioned process is simple and easy to operate, and has become a routine operation method for recycling waste lithium-ion batteries. However, inorganic acids or organic acids containing reducing agents are usually used as leaching reagents in the acid leaching process, which is likely to cause serious equipment corrosion and secondary damage. In the subsequent stage of impurity removal and separation of the leaching solution, it is easy to form colloids in the process of acid adjustment to prepare hydroxide precursors, and it is easy to cause a large amount of entrainment loss of lithium ions in the filtration process, resulting in low comprehensive resource recovery. high.

In order to solve the above technical problems, many researchers and enterprises have carried out improvement research on acid leaching, purification, separation and other links, and proposed many improved processes.

CN107058742A proposes a method for recovering lithium from waste lithium ion batteries. The battery powder is obtained by dismantling and crushing the waste lithium-ion battery, and the acid solution of the battery powder is purified to obtain a lithium-containing material solution, and then acid-adjusted, extracted, washed, back-extracted, degreased, evaporated, cooled and crystallized, Filtration, drying and other processes finally obtain anhydrous lithium salt. This method requires multi-step impurity removal operations, the process is complicated, waste residue and waste water are easily generated, and the steps of leachate purification, acid adjustment, extraction and other steps will cause lithium entrainment loss to varying degrees, resulting in a low comprehensive recovery rate of lithium.

CN106654437A proposes a method for recovering lithium from lithium-containing batteries. The waste lithium-ion battery is short-circuit discharged, disassembled, mechanically crushed, and heat-treated to obtain the battery material, and the electrolyte is poured into the sodium hydroxide solution with ethanol as the solvent to obtain a mixed solution, and the mixed solution is mixed with the leachate of the battery material. Carry out vacuum rectification under reduced pressure to remove the organic solvent, add solid sodium carbonate and then recrystallize to obtain lithium carbonate. The method uses a sodium hydroxide solution containing a large amount of organic solvents to adjust the pH of the acid leaching solution, which greatly reduces the concentration of lithium ions in the acid leaching solution, resulting in a low lithium precipitation rate in the subsequent preparation of lithium carbonate, thereby reducing the overall recovery rate of lithium. , and the introduction of organic reagents increases the processing burden and energy consumption of the subsequent separation process.

CN107394298A proposes a lithium resource recovery method on the negative electrode sheet of the waste lithium ion battery. The fine powder is obtained by ball milling and sieving after the massive powder on the surface of the negative electrode sheet is peeled off, and the powder is added to dilute hydrochloric acid for leaching reaction, and at the same time, it is supplemented by ultrasonic stirring to form a suspension; after filtration, the pH of the filtrate is adjusted to 5 -8, after filtering again, evaporate and concentrate the filtrate and add saturated sodium carbonate solution in the temperature range of 80-100°C to obtain lithium carbonate precipitate, and the obtained lithium carbonate precipitate is washed and dried to obtain high-purity lithium carbonate powder. This method is easy to operate, but this method uses hydrochloric acid as the leaching reagent, and adjusts the pH of the secondary filtrate with high-concentration ammonia water, resulting in a large investment in leaching equipment anticorrosion and gas purification equipment, and this method is not suitable for those containing a variety of valuable metals. Elemental positive electrode waste treatment process.

CN106848471A proposes a mixed acid leaching and recycling method for waste lithium-ion battery cathode materials. The method is to crush and dry the lithium cobaltate positive electrode waste and carry out reduction pre-leaching in the mixed acid. The obtained pre-leaching slag is ball-milled and then leached for the first time, and the leaching solution containing cobalt and lithium is obtained after the second leaching, and the acid of the leaching solution is adjusted. , filtered, evaporated and concentrated, and saturated sodium carbonate solution was added, filtered, washed and dried to finally obtain high-purity lithium carbonate solid. This method uses ball milling and acid leaching operations for many times, which is cumbersome to operate, and the cobalt in the leaching solution is removed in the form of cobalt hydroxide through subsequent acid adjustment, which will cause a certain degree of entrainment loss of lithium ions.

CN105742744A proposes a method for extracting lithium from the lithium-containing waste liquid produced in the recycling process of waste lithium-ion batteries. In the method, sodium carbonate is added into the lithium-containing waste liquid for stirring reaction, and crude lithium carbonate and lithium sinking are obtained after filtration. The obtained crude lithium carbonate and manganese carbonate are mixed evenly and roasted to obtain sodium-containing spinel-type lithium manganate; the obtained lithium-precipitated liquid is cooled and crystallized to separate sodium carbonate, and sodium phosphate lithium is deposited to finally obtain phosphoric acid lithium. This method realizes the efficient recovery and utilization of lithium resources in lithium-containing wastewater, but the process is complicated, the operation is complicated and time-consuming, and at the same time, high-temperature roasting operation is used to prepare lithium manganate, and the process consumes a lot of energy.

Therefore, it is of great significance in this field to develop a method for extracting lithium from lithium-containing battery waste with wide applicability, no emissions, mild reaction conditions, and high selectivity and extraction rate of lithium.

Contents of the invention

In view of the above-mentioned deficiencies in the prior art, the object of the present invention is to provide a method for selectively extracting lithium from lithium-containing battery waste. In the method provided by the invention, in a solution containing compounds with strong oxidation properties, the highly selective extraction of lithium elements in lithium-containing battery waste can be realized in one step by controlling the redox properties of the system. The method provided by the invention not only has short process, simple operation, but also has wide applicability, no discharge, and high selectivity and extraction rate of lithium.

For reaching above-mentioned purpose, the present invention adopts following technical scheme:

The invention provides a method for extracting lithium from lithium-containing battery waste, the method comprising the steps of:

(1) mixing the pretreated lithium-containing battery waste with an aqueous oxide solution, performing a leaching reaction on the obtained raw material slurry, and obtaining the leaching slurry after the reaction;

(2) adjusting the pH of the leaching slurry in step (1) to 7-13, and performing solid-liquid separation on the obtained reaction slurry to obtain a solid slag and a lithium-containing purification solution;

(3) Add carbonate to the lithium-containing purification solution described in step (2), carry out the lithium sinking reaction, and separate the solid and liquid after the reaction to obtain the lithium carbonate product and the lithium sinking tail liquid, and the described lithium sinking tail liquid is adjusted to be acidic Back in the leaching reaction system of step (1).

The method provided by the invention controls the oxidation-reduction characteristics of the system, utilizes the aqueous oxide solution to realize the highly selective extraction of the lithium element in the lithium-containing battery waste in one step, and suppresses the leaching process of other valuable metal elements.

In the method provided by the invention in step (1), the lithium-containing battery waste used is pretreated before being mixed with the aqueous oxide solution. The purpose of the pretreatment is to remove aluminum and copper in the lithium-containing battery waste in advance, because this The composition of the lithium-containing battery waste treated by the invention is relatively complex. If the aluminum and copper in the waste are not removed before leaching, the subsequent leaching reaction and separation and impurity removal process will be affected.

In step (2) of the method provided by the present invention, the pH of the leach slurry described in step (1) is adjusted to 7-13, such as 7, 8, 8.5, 9, 9.5, 10, 10.4, 11.1, 11.6, 12 or 13, etc., but not limited to the listed values, other unlisted values within this range are also applicable. This step adjusts the pH for deep impurity removal. In the present invention, because the components of lithium-containing battery waste used are relatively complex, it is difficult to ensure the complete removal of foreign ions such as aluminum and copper in the pretreatment process, and a small amount of valuable metals such as nickel, aluminum, copper, etc. will enter the leaching reaction stage. solution, so after leaching, it is necessary to adjust the pH to 7-13 for deep impurity removal, so as to obtain a purer lithium-containing purification solution.

In the present invention, after the lithium sinking tail liquid is obtained in step (3), the lithium sinking tail liquid is acid-adjusted and then returned to the leaching process of step (1), so that it can be recycled, further reducing the actual consumption and operating cost of the overall process , and fundamentally solved the problem of wastewater discharge, and realized zero discharge. In addition, this cyclic operation also helps to improve the comprehensive recovery rate of lithium in the method of the present invention.

The following are preferred technical solutions of the present invention, but not as limitations on the technical solutions provided by the present invention. Through the following preferred technical solutions, the technical objectives and beneficial effects of the present invention can be better achieved and realized.

As a preferred technical solution of the present invention, in step (1), the pretreatment includes any one or at least two of mechanical crushing, ball milling, gravity separation, magnetic separation, mechanochemical treatment, organic solvent dissolution, roasting or alkali leaching. The combination of species, a typical but non-limiting combination is: the combination of mechanical crushing and ball milling, the combination of gravity separation and magnetic separation, the combination of mechanochemical treatment and organic solvent dissolution, the combination of roasting or alkali leaching, etc., preferably mechanical crushing Combination of , gravity separation, roasting and alkali leaching. The advantage of using this pretreatment method is that the copper, aluminum, organic binder and other components in the waste can be effectively removed through the process of mechanical crushing, gravity separation and roasting, and can be removed by alkali leaching Aluminum components remain in the waste, and these operations can be used in combination to more fully remove impurities such as aluminum and copper before the leaching operation, which is beneficial to the subsequent leaching operation and the ultimate realization of high-selectivity lithium extraction.

As a preferred technical solution of the present invention, in step (1), the lithium-containing battery waste includes lithium cobaltate, lithium nickelate, lithium manganate, lithium nickel cobaltate, lithium nickel manganate, lithium cobalt manganate, nickel cobalt Manganese ternary, nickel-cobalt-aluminum ternary, lithium-containing alloy negative electrode, lithium titanate negative electrode or lithium-containing graphite negative electrode, or any combination of at least two, typical but non-limiting combinations are: lithium cobaltate and nickel Combination of lithium manganese oxide, combination of lithium manganese oxide and lithium nickel cobalt oxide, combination of lithium nickel manganese oxide and lithium cobalt manganese oxide, combination of lithium cobalt manganese oxide and nickel-cobalt-manganese ternary, nickel-cobalt-aluminum ternary and lithium-containing alloys combination of negative poles, etc.

Preferably, in step (1), the lithium-containing battery waste material comes from full battery powder obtained after discharging and crushing waste lithium-ion batteries, positive electrode materials obtained after dismantling waste lithium-ion batteries, disassembled waste lithium-ion batteries, etc. Any one or a combination of at least two of the negative electrode materials obtained after decomposition, the positive and negative electrode scraps generated during the lithium battery production process, or the defective product waste generated during the lithium battery production process.

As a preferred technical solution of the present invention, in step (1), the oxide aqueous solution is perchlorate aqueous solution, permanganate aqueous solution, ferrate aqueous solution, Fenton's reagent aqueous solution, Fenton-like reagent aqueous solution, persulfuric acid Any one or a combination of at least two of saline solution, ozone solution or hydrogen peroxide solution, typical but non-limiting combinations include: a combination of perchlorate solution and permanganate solution, ferrate solution and The combination of Fenton's reagent aqueous solution, the combination of Fenton-like reagent aqueous solution and persulfate aqueous solution, the combination of ozone aqueous solution and hydrogen peroxide aqueous solution, etc.

Preferably, the aqueous ozone solution contains activated carbon.

As a preferred technical solution of the present invention, in step (1), it also includes: preheating the raw material slurry before performing the leaching reaction.

Preferably, the raw material slurry is preheated to a temperature of 25-200°C, such as 25°C, 30°C, 40°C, 50°C, 60°C, 66°C, 72°C, 78°C, 82°C, 94°C, 96°C °C, 100 °C, 150 °C or 200 °C, etc., but not limited to the listed values, other unlisted values within this range are also applicable, preferably 50-150 °C, more preferably 60-100 °C.

Preferably, in step (1), the leaching reaction is carried out in a reactor.

Preferably, the reactor is an open reactor or a closed reactor, preferably a closed reactor at normal pressure. In the present invention, when the closed reactor is used, the liquid phase substances in the reaction system will not volatilize due to heating, so there is no need to add solvent midway, which improves the operability of the method of the present invention. The normal pressure closed reactor can achieve better results.

Preferably, in step (1), the leaching reaction is accompanied by stirring.

Preferably, the stirring is any one or a combination of at least two of magnetic stirring, mechanical stirring or gas stirring, preferably mechanical stirring.

Preferably, in step (1), the leaching reaction time is 0.5-48h, such as 0.5h, 1h, 2h, 2.5h, 3.2h, 4.3h, 5.6h, 6.2h, 7.7h, 8.0h, 8.4h h, 9.2h, 9.6h, 10.0h, 20h, 35h, 46h or 48h, etc., but not limited to the listed values, other unlisted values within this range are also applicable, preferably 1-12h, more preferably 2-12h.

As a preferred technical solution of the present invention, in step (2), the pH of the leach slurry in step (1) is adjusted to 8-11. In the present invention, adjusting the pH of the leaching slurry to 8-11 is more conducive to removing traces of valuable metal ions in the leachate, and at the same time does not cause Al(OH) ₃ to redissolve to form metaaluminate.

Preferably, in step (2), the pH of the leach slurry in step (1) is adjusted with an alkaline substance.

Preferably, the alkaline substance includes any one or a combination of at least two of sodium hydroxide, potassium hydroxide, ammonia water or ammonium salts. Typical but non-limiting combinations include: the combination of sodium hydroxide and potassium hydroxide, the combination of potassium hydroxide and ammonia water, the combination of ammonia water and ammonium salt, and the like.

Preferably, in step (2), the solid-liquid separation is filtration separation and/or centrifugal separation, preferably filtration separation. In the present invention, the filtration separation and/or centrifugal separation refer to filtration separation, centrifugal separation, or a combination of filtration separation and centrifugal separation.

As a preferred technical solution of the present invention, in step (3), the carbonate includes sodium carbonate and/or potassium carbonate, preferably sodium carbonate. Among the present invention, described sodium carbonate and/or potassium carbonate refer to can be sodium carbonate, also can be potassium carbonate, can also be the combination of sodium carbonate and potassium carbonate.

As a preferred technical solution of the present invention, in step (3), the temperature of the lithium precipitation reaction is above 25°C, such as 25°C, 50°C, 75°C, 81°C, 86°C, 88°C, 90°C, 92°C , 94°C, 98°C, 100°C or 150°C, etc., preferably 80-100°C.

Preferably, in step (3), the time for the lithium precipitation reaction is 1-10h, such as 1.0h, 2.0h, 2.3h, 3.1h, 3.5h, 4.6h, 5.1h, 5.8h, 6.0h, 7.5h h, 8.3h, 9.1h or 10.0h, etc., preferably 2-6h.

Preferably, in step (3), the solid-liquid separation is filtration separation and/or centrifugal separation, preferably filtration separation. In the present invention, the filtration separation and/or centrifugal separation refer to filtration separation, centrifugal separation, or a combination of filtration separation and centrifugal separation.

As a preferred technical solution of the present invention, in step (3), an acidic substance is used to adjust the acidity and alkalinity of the lithium precipitation tail liquid.

Preferably, the acidic substance includes any one or a combination of at least two of sulfuric acid, hydrochloric acid, nitric acid, phosphoric acid or strong acid and weak base salts. Typical but non-limiting combinations include: the combination of sulfuric acid and hydrochloric acid, the combination of hydrochloric acid and nitric acid Combination, combination of nitric acid and phosphoric acid, combination of phosphoric acid and strong acid and weak base salt, etc.

As a further preferred technical solution of the method of the present invention, the method comprises the following steps:

(1) Mix the pretreated lithium-containing battery waste with the aqueous oxide solution to obtain a raw material slurry, preheat the raw material slurry to 60-100°C, and then place it in an airtight reactor at atmospheric pressure, and carry out under mechanical stirring conditions Leaching reaction, the reaction time is 2-12h, and the leaching slurry is obtained after the reaction; wherein, the pretreatment is a combination of mechanical crushing, gravity separation, roasting and alkali leaching;

(2) adjusting the pH of the leaching slurry in step (1) to 8-11 with an alkaline substance, and filtering and separating the obtained reaction slurry to obtain a solid slag and a lithium-containing purification solution;

(3) Add sodium carbonate to the lithium-containing purification solution described in step (2), carry out a lithium precipitation reaction at 80-100° C., the reaction time is 2-6 hours, and filter and separate after the reaction to obtain lithium carbonate product and lithium precipitation tail liquid , the lithium sinking tail liquid is returned to the leaching reaction system of step (1) after being adjusted to be acidic with an acidic substance.

Compared with the prior art, the present invention has the following beneficial effects:

(1) The method for selectively extracting lithium from lithium-containing battery waste provided by the present invention has wide applicability, and can be used for lithium cobaltate, lithium manganate, lithium nickelate, binary and ternary materials, lithium-containing negative electrode materials, etc. Selective lithium extraction process of various battery wastes;

(2) The method for selectively extracting lithium from lithium-containing battery waste provided by the present invention has short process flow, simple and convenient operation, mild reaction conditions, low cost of reaction raw materials, non-toxic and harmless, simple leachate components, and is easy to handle;

(3) The whole process of the method for selectively extracting lithium from lithium-containing battery waste provided by the present invention adopts low temperature and normal pressure operation, and realizes the internal circulation of the medium, greatly reducing the consumption of reaction reagents, and the whole process has no waste water and waste gas or waste discharge;

(4) The method for selectively extracting lithium from lithium-containing battery waste provided by the present invention realizes the highly selective recovery of lithium resources in lithium-containing battery waste, the extraction selectivity of lithium reaches more than 95%, and the single extraction rate reaches 90% % or more, through the use of recycling operations, the comprehensive recovery rate of lithium can reach more than 99.9%, in addition, it also plays a role in enriching other valuable metals in the positive electrode material.

Description of drawings

Figure 1 is a process flow diagram of the method for selectively extracting lithium from lithium-containing battery waste provided by Example 1 of the present invention.

Detailed ways

In order to better illustrate the present invention and facilitate understanding of the technical solution of the present invention, the present invention will be further described in detail below. However, the following embodiments are only simple examples of the present invention, and do not represent or limit the protection scope of the present invention, and the protection scope of the present invention shall be determined by the claims.

The following are typical but non-limiting embodiments of the present invention:

Example 1

This embodiment provides a method for selectively extracting lithium from lithium-containing battery waste, the specific method is:

(1) Add the NCM523 positive electrode material that has been mechanically pulverized and pretreated to be below 100 mesh into 12wt.% potassium ferrate solution to obtain a raw material slurry, and preheat it to 95° C., with a solid-to-liquid ratio of 25 g/L; The raw material slurry is placed in a closed reactor at atmospheric pressure, and the leaching reaction is carried out to selectively extract lithium. Mechanical stirring is used to ensure that the positive electrode material is evenly suspended in the solution. The stirring speed is 400rpm, and the reaction is 5.5h. After the reaction, the leaching slurry is obtained.

(2) Add KOH to the leaching slurry obtained in step (1), adjust the pH of the solution to 11.0, and remove impurities in depth to obtain a reaction slurry, and directly filter the resulting reaction slurry to obtain nickel-cobalt-manganese-rich Collect slag and lithium-containing leachate.

(3) Slowly add 5 mol/L K ₂ CO ₃ solution to the lithium-containing leaching solution obtained in step (2), mechanically stir the reaction at 89° C. for 5.5 hours, and obtain lithium carbonate product through filtration and separation. The lithium precipitation tail liquid obtained by filtration and separation is adjusted to be acidic with an acidic substance and then returned to the leaching reaction system of step (1) to realize recycling and ensure no discharge of three wastes.

The process flow chart of the method for selectively extracting lithium from lithium-containing battery waste provided in this example is shown in FIG. 1 .

In this embodiment, atomic emission spectrometer (ICP) was used to measure the content of each metal element in the lithium-containing leaching solution. The test results showed that the lithium leaching rate reached 96.26%. Cobalt and manganese elements exist; the obtained lithium carbonate product is washed and dried and the content of lithium is measured by ICP, and the calculated lithium carbonate product purity is 99.43%. In this embodiment, the extraction selectivity of lithium is 98.25%, the single extraction rate of lithium is 92.41%, and the comprehensive recovery rate of lithium is 99.94% by adopting the cycle operation.

Example 2

This embodiment provides a method for selectively extracting lithium from lithium-containing battery waste, the specific method is:

(1) Add the lithium cobalt oxide full battery powder that has been roasted at 500°C before removing the aluminum foil to 20wt.% Fenton’s solution to prepare a raw material slurry, and preheat it to 75°C with a solid-to-liquid ratio of 10g/L Place the prepared raw material slurry in an airtight reactor at normal pressure for leaching reaction, use mechanical stirring to ensure that the positive electrode material is evenly suspended in the solution, stir at a speed of 300 rpm, react for 4.2 hours, and obtain the leaching slurry after the reaction is completed.

(2) adding NaOH to the leaching slurry obtained in step (1), adjusting the pH of the solution to 10.5 to obtain a reaction slurry; directly filtering the obtained reaction slurry to obtain a cobalt-rich enrichment slag and a lithium-containing leachate.

(3) Slowly add Na ₂ CO ₃ solid particles to the lithium-containing leaching solution obtained in step (2), mechanically stir the reaction at 100° C. for 5 hours, and obtain lithium carbonate product through filtration and separation. The lithium precipitation tail liquid obtained by filtration and separation is adjusted to be acidic with an acidic substance and then returned to the leaching reaction system of step (1) to realize recycling and ensure no discharge of three wastes.

In this embodiment, ICP is used to measure the content of each metal element in the lithium-containing leachate, and the calculated lithium dissolution rate reaches 96.35%, and the presence of cobalt, aluminum, copper, iron and other ions is not detected in the leachate; the obtained lithium carbonate product is washed and dried Utilize ICP to measure the content of lithium wherein in the back, calculate lithium carbonate product purity to be 99.68%. In this embodiment, the extraction selectivity of lithium is 99.48%, the single extraction rate of lithium is 92.50%, and the comprehensive recovery rate of lithium is 99.92% by adopting the cycle operation.

Example 3

This embodiment provides a method for selectively extracting lithium from lithium-containing battery waste, the specific method is:

(1) Add the lithium manganate positive electrode powder, which has previously removed the aluminum foil in the NaOH solution, into hydrogen peroxide containing 5v/v% to prepare a raw material slurry, and preheat it to 60°C, with a solid-to-liquid ratio of 10g/L; The prepared raw material slurry is placed in a closed reactor at atmospheric pressure for leaching reaction, and O ₃ is continuously bubbled into the solution through an ozone generator, and mechanical stirring is used to ensure that the positive electrode material is evenly suspended in the solution. The stirring speed is 150rpm, and the reaction is 12h. After the reaction is finished, a leach slurry is obtained.

(2) adding NaOH to the leaching slurry obtained in step (1), adjusting the pH of the solution to 9.8 to obtain a reaction slurry; directly filtering the obtained reaction slurry to obtain a manganese-rich enrichment slag and a lithium-containing leachate.

(3) Slowly add Na ₂ CO ₃ solid particles to the lithium-containing leaching solution obtained in step (2), mechanically stir the reaction at 87° C. for 4.3 hours, and obtain lithium carbonate product through filtration and separation. The lithium precipitation tail liquid obtained by filtration and separation is adjusted to be acidic with an acidic substance and then returned to the leaching reaction system of step (1) to realize recycling and ensure no discharge of three wastes.

In the present embodiment, the content of each metal element in the lithium-containing leachate was measured by ICP, and the lithium dissolution rate was calculated to reach 97.63%, and the presence of manganese and aluminum ions was not detected in the leachate; the obtained lithium carbonate product was washed and dried by ICP. Wherein the content of lithium, the calculation lithium carbonate product purity is 99.14%. In this embodiment, the extraction selectivity of lithium is 99.85%, the single extraction rate of lithium is 93.72%, and the comprehensive recovery rate of lithium is 99.93% by adopting cyclic operation.

Example 4

This embodiment provides a method for selectively extracting lithium from lithium-containing battery waste, the specific method is:

(1) Add the lithium nickelate full battery powder that has been roasted at 600°C for 3 hours before removing the aluminum foil into a 15wt.% ammonium persulfate solution to prepare a raw material slurry, and preheat it to 100°C with a solid-to-liquid ratio of 15g /L; Place the prepared raw material slurry in a closed reactor at atmospheric pressure for leaching reaction, use mechanical stirring to ensure that the positive electrode material is evenly suspended in the solution, the stirring speed is 450rpm, react for 2.0h, and the leaching slurry is obtained after the reaction is completed.

(2) adding ammonia water to the leaching slurry obtained in step (1), adjusting the pH of the solution to 8.0 to obtain a reaction slurry; directly filtering the obtained reaction slurry to obtain a nickel-rich enrichment slag and a lithium-containing leachate. Slowly add Na ₂ CO ₃ solid particles into the lithium-containing leaching solution obtained in step (2) by mining (3), mechanically stir the reaction at 93°C for 2.8 hours, and obtain lithium carbonate product through filtration and separation. The lithium precipitation tail liquid obtained by filtration and separation is adjusted to be acidic with an acidic substance and then returned to the leaching reaction system of step (1) to realize recycling and ensure no discharge of three wastes.

In the present embodiment, use ICP to measure the content of each metal element in the lithium-containing leaching solution, and the calculated lithium dissolution rate reaches 95.89%, and the nickel ion content in the leaching solution is 0.52mg/L, and the existence of aluminum, copper and other ions is not detected; After the lithium product is washed and dried, utilize ICP to measure the content of lithium therein, and the calculated lithium carbonate product purity is 99.08%. In this embodiment, the extraction selectivity of lithium is 99.56%, the single extraction rate of lithium is 92.05%, and the comprehensive recovery rate of lithium is 99.97% by adopting cyclic operation.

Example 5

This embodiment provides a method for selectively extracting lithium from lithium-containing battery waste, the specific method is:

(1) Add the NCM111 positive electrode powder that has been roasted at 500°C and remove the aluminum foil in advance to 15wt.% perchloric acid solution to prepare a raw material slurry, and preheat it to 65°C with a solid-to-liquid ratio of 15g/L; The prepared raw material slurry was placed in a closed reactor at normal pressure for leaching reaction, and mechanical stirring was used to ensure that the positive electrode material was evenly suspended in the solution at a stirring speed of 350 rpm. The reaction was carried out for 10.5 hours, and the leaching slurry was obtained after the reaction was completed.

(2) Add KOH to the leaching slurry obtained in step (1), adjust the pH of the solution to 9.6 to obtain a reaction slurry; directly filter the resulting reaction slurry to obtain enriched slag rich in nickel, cobalt and manganese and lithium-containing leachate .

(3) Slowly add K ₂ CO ₃ solid particles to the lithium-containing leaching solution obtained in step (2), mechanically stir the reaction at 91° C. for 3.4 hours, and obtain lithium carbonate product through filtration and separation. The lithium precipitation tail liquid obtained by filtration and separation is adjusted to be acidic with an acidic substance and then returned to the leaching reaction system of step (1) to realize recycling and ensure no discharge of three wastes.

In this example, ICP was used to measure the content of each metal element in the lithium-containing leaching solution, and the calculated lithium dissolution rate reached 97.64%. The contents of nickel ions and aluminum ions in the leaching solution were 0.14 and 0.09 mg/L respectively, and no cobalt and manganese ions were detected. The existence of; Gained Lithium Retard product is washed, dried and utilized ICP to measure the content of lithium wherein, calculates Lithium Retard product purity to be 98.95%. In this embodiment, the extraction selectivity of lithium is 99.28%, the single extraction rate of lithium is 93.73%, and the comprehensive recovery rate of lithium is 99.68% by adopting cyclic operation.

Example 6

This embodiment provides a method for selectively extracting lithium from lithium-containing battery waste, the specific method is:

(1) Add the NCM811 positive electrode powder that has been alkaline leached in KOH solution to remove the aluminum foil in advance into 20wt.% potassium permanganate solution to prepare raw material slurry, and preheat it to 80°C with a solid-to-liquid ratio of 20g/L Place the prepared raw material slurry in a sealed reactor at normal pressure for leaching reaction, use mechanical stirring to ensure that the positive electrode material is evenly suspended in the solution, the stirring speed is 380rpm, react for 7.5h, and the leaching slurry is obtained after the reaction is completed.

(2) Add KOH to the leaching slurry obtained in step (1), adjust the pH of the solution to 10.6 to obtain a reaction slurry; directly filter the resulting reaction slurry to obtain enriched slag rich in nickel, cobalt, manganese and lithium-containing leachate .

(3) Slowly add K ₂ CO ₃ solid particles to the lithium-containing leaching solution obtained in step (2), mechanically stir the reaction at 85° C. for 6 hours, and obtain lithium carbonate product through solid-liquid separation. The lithium precipitation tail liquid obtained by solid-liquid separation is adjusted to be acidic with an acidic substance and then returned to the leaching reaction system in step (1) to realize recycling and ensure no discharge of three wastes.

In the present embodiment, the content of each metal element in the lithium-containing leaching solution was measured by ICP, and the calculated lithium dissolution rate reached 98.15%, and the presence of cobalt, nickel, manganese, aluminum, copper, iron and other ions was not detected in the leaching solution; the obtained lithium carbonate After the product is washed and dried, utilize ICP to measure the content of lithium therein, and the calculated lithium carbonate product purity is 99.62%. In this embodiment, the extraction selectivity of lithium is 99.09%, the single extraction rate of lithium is 94.22%, and the comprehensive recovery rate of lithium is 99.89% by adopting the cycle operation.

Example 7

This embodiment provides a method for selectively extracting lithium from lithium-containing battery waste, the specific method is:

(1) Add the NCA111 powder that has been roasted at 500°C before removing the aluminum foil to 20wt.% Fe(III)-oxalic acid solution to prepare a raw material slurry, and preheat it to 70°C with a solid-to-liquid ratio of 5g/L ; Place the prepared raw material slurry in a normal pressure open reactor for leaching reaction, use mechanical stirring to ensure that the positive electrode material is evenly suspended in the solution, the stirring speed is 320rpm, and react for 8 hours. During the reaction, slowly add water to the system to compensate for evaporation loss, the reaction ends to obtain leaching slurry.

(2) Add NaOH to the leaching slurry obtained in step (1), adjust the pH of the solution to 10.2 to obtain a reaction slurry; directly filter the resulting reaction slurry to obtain enriched slag rich in nickel, cobalt and aluminum and lithium-containing leachate .

(3) Slowly add Na ₂ CO ₃ solid particles to the lithium-containing leaching solution obtained in step (2), mechanically stir the reaction at 95° C. for 2 h, and obtain lithium carbonate product through solid-liquid separation. The lithium precipitation tail liquid obtained by solid-liquid separation is adjusted to be acidic with an acidic substance and then returned to the leaching reaction system in step (1) to realize recycling and ensure no discharge of three wastes.

In this embodiment, ICP is used to measure the content of each metal element in the lithium-containing leaching solution, and the calculated lithium dissolution rate reaches 97.93%, and the presence of cobalt, nickel, aluminum and other ions is not detected in the leaching solution; the obtained lithium carbonate product is washed and dried for use ICP measures the content of lithium wherein, calculates that lithium carbonate product purity is 98.46%. In this embodiment, the extraction selectivity of lithium is 99.67%, the single extraction rate of lithium is 94.01%, and the comprehensive recovery rate of lithium is 99.35% by adopting the cycle operation.

Example 8

This embodiment provides a method for selectively extracting lithium from lithium-containing battery waste, the specific method is:

(1) Add NCM811 positive electrode powder, which has been alkaline leached in KOH solution to remove aluminum foil, into 20wt.% potassium permanganate solution to prepare raw material slurry, and preheat it to 25°C with a solid-to-liquid ratio of 20g/L Place the prepared raw material slurry in a sealed reactor at normal pressure for leaching reaction, use mechanical stirring to ensure that the positive electrode material is evenly suspended in the solution, the stirring speed is 380rpm, react for 48h, and the leaching slurry is obtained after the reaction is completed.

(2) Add KOH to the leaching slurry obtained in step (1), adjust the pH of the solution to 13 to obtain a reaction slurry; directly filter the resulting reaction slurry to obtain enriched slag rich in nickel, cobalt and manganese and lithium-containing leaching solution .

(3) Slowly add K ₂ CO ₃ solid particles to the lithium-containing leaching solution obtained in step (2), mechanically stir the reaction at 80° C. for 1 h, and obtain lithium carbonate product through solid-liquid separation. The lithium precipitation tail liquid obtained by solid-liquid separation is adjusted to be acidic with an acidic substance and then returned to the leaching reaction system in step (1) to realize recycling and ensure no discharge of three wastes.

In the present embodiment, the content of each metal element in the lithium-containing leaching solution was measured by ICP, and the calculated lithium dissolution rate reached 95.69%, and the presence of cobalt, nickel, manganese, aluminum, copper, iron and other ions was not detected in the leaching solution; the obtained lithium carbonate After the product is washed and dried, utilize ICP to measure the content of lithium therein, and the calculated lithium carbonate product purity is 98.76%. In this embodiment, the extraction selectivity of lithium is 99.19%, the single extraction rate of lithium is 91.86%, and the comprehensive recovery rate of lithium is 99.28% by adopting the cycle operation.

Example 9

This embodiment provides a method for selectively extracting lithium from lithium-containing battery waste, the specific method is:

(1) Add the NCA111 powder that has been roasted at 500°C before removing the aluminum foil to 20wt.% Fe(III)-oxalic acid solution to prepare a raw material slurry, and preheat it to 200°C with a solid-to-liquid ratio of 5g/L ; Place the prepared raw material slurry in a normal pressure open reactor for leaching reaction, use mechanical stirring to ensure that the positive electrode material is evenly suspended in the solution, the stirring speed is 320rpm, and react for 0.5h. During the reaction process, slowly add water to the system to compensate Evaporation loss, the end of the reaction to obtain leached slurry.

(2) Add NaOH to the leaching slurry obtained in step (1), adjust the pH of the solution to 7 to obtain a reaction slurry; directly filter the resulting reaction slurry to obtain enriched slag rich in nickel, cobalt and aluminum and lithium-containing leaching solution .

(3) Slowly add Na ₂ CO ₃ solid particles to the lithium-containing leaching solution obtained in step (2), mechanically stir the reaction for 10 h at 25° C., and obtain lithium carbonate product through solid-liquid separation. The lithium precipitation tail liquid obtained by solid-liquid separation is adjusted to be acidic with an acidic substance and then returned to the leaching reaction system in step (1) to realize recycling and ensure no discharge of three wastes.

In this embodiment, ICP is used to measure the content of each metal element in the lithium-containing leaching solution, and the calculated lithium dissolution rate reaches 96.43%, and the presence of cobalt, nickel, aluminum and other ions is not detected in the leaching solution; the obtained lithium carbonate product is washed and dried for use ICP measures the content of lithium wherein, calculates that lithium carbonate product purity is 98.16%. In this embodiment, the extraction selectivity of lithium is 99.51%, the single extraction rate of lithium is 36.42%, and the comprehensive recovery rate of lithium is 76.43% by adopting the cycle operation.

Example 10

This implementation provides a method for selectively extracting lithium from lithium-containing battery waste. For the specific method, refer to Example 4. The difference is that in step (1), the preheating temperature of the raw material slurry is 150 ° C, and the time for the leaching reaction is is 1h; in step (3), the reaction time of lithium precipitation is 1h.

In the present embodiment, use ICP to measure the content of each metal element in the lithium-containing leaching solution, and the calculated lithium dissolution rate reaches 98.47%, and the nickel ion content in the leaching solution is 0.41mg/L, and the existence of aluminum, copper and other ions is not detected; After the lithium product is washed and dried, utilize ICP to measure the content of lithium therein, and the calculated lithium carbonate product purity is 99.08%. In this embodiment, the extraction selectivity of lithium is 99.82%, the single extraction rate of lithium is 94.53%, and the comprehensive recovery rate of lithium is 99.92% by adopting the circulation operation.

Example 11

This example provides a method for selectively extracting lithium from lithium-containing battery waste. The specific method refers to Example 3, the difference is that in step (1), the preheating temperature of the raw material slurry is 50°C.

In the present embodiment, the content of each metal element in the lithium-containing leachate was measured by ICP, and the lithium dissolution rate was calculated to reach 95.86%, and the presence of manganese and aluminum ions was not detected in the leachate; the obtained lithium carbonate product was washed and dried and measured by ICP Wherein the content of lithium, the calculation lithium carbonate product purity is 99.18%. In this embodiment, the extraction selectivity of lithium is 99.83%, the single extraction rate of lithium is 92.03%, and the comprehensive recovery rate of lithium is 99.75% by adopting the cycle operation.

Example 12

This embodiment provides a method for selectively extracting lithium from lithium-containing battery waste. For the specific method, refer to Example 1. The difference is that in step (1), the pretreatment method is to perform mechanical crushing first, and then re-election , followed by roasting and alkali leaching.

In this example, ICP was used to measure the content of each metal element in the lithium-containing leaching solution. The test results showed that the lithium leaching rate reached 97.28%, the contents of nickel and aluminum elements in the leaching solution were 0.16 and 0.08 mg/L respectively, and no cobalt and manganese elements were detected. Exist; Gained Lithium Retard product is washed, dried and utilized ICP to measure the content of lithium wherein, calculates Lithium Retard product purity to be 99.51%. In this embodiment, the extraction selectivity of lithium is 99.45%, the single extraction rate of lithium is 93.39%, and the comprehensive recovery rate of lithium is 99.96% by adopting the cycle operation.

Comparative example 1

The specific method of this comparative example refers to Example 3, the difference is that in step (2), the pH of the leaching slurry is adjusted to 5.

In this comparative example, the content of each metal element in the lithium-containing leaching solution was measured by ICP, and the lithium dissolution rate was calculated to reach 97.75%, and the presence of manganese and aluminum ions was not detected in the leaching solution; the obtained lithium carbonate product was washed and dried and measured by ICP Wherein the content of lithium, the calculation lithium carbonate product purity is 99.06%. In this comparative example, the extraction selectivity of lithium is 99.81%, the single extraction rate of lithium is 28.41%, and the comprehensive recovery rate of lithium is 46.19% by adopting the circulation operation.

Comparative example 2

The specific method of this comparative example refers to Example 2. The difference is that in step (1), the lithium cobalt oxide full battery powder is not pretreated to remove the aluminum foil after being roasted at 500 ° C, and the unpretreated lithium cobalt oxide full battery is directly The battery powder was added into 20wt.% Fenton's solution to prepare raw material slurry.

In this comparative example, the content of each metal element in the lithium-containing leachate was measured by ICP, and the lithium dissolution rate was calculated to reach 95.69%, and the aluminum ion content in the leachate was as high as 80mg/L; after the obtained lithium carbonate product was washed and dried, the lithium carbonate product was measured by ICP. content, the calculated lithium carbonate product purity is 99.72%. In this comparison example, the extraction selectivity of lithium is 40.83%, the single extraction rate of lithium is 89.17%, and the comprehensive recovery rate of lithium is 92.15% by adopting the circulation operation.

Based on the above examples and comparative examples, it can be seen that the method for selectively extracting lithium from lithium-containing battery waste provided by the present invention has wide applicability, and can be used for the selective lithium extraction process of various battery waste materials; the process is short and easy to operate , the reaction conditions are mild, the cost of reaction raw materials is low, non-toxic and harmless, the composition of the leachate is simple, and it is easy to handle; the internal circulation of the medium is realized, the consumption of reaction reagents is greatly reduced, and the whole process has no waste water, waste gas or waste residue discharge; Highly selective recovery of lithium resources from lithium-containing battery waste. The comparative example does not adopt the solution of the present invention, thus the effect of the present invention cannot be obtained.

The applicant declares that the present invention illustrates the detailed process equipment and process flow of the present invention through the above-mentioned examples, but the present invention is not limited to the above-mentioned detailed process equipment and process flow, that is, it does not mean that the present invention must rely on the above-mentioned detailed process equipment and process flow process can be implemented. Those skilled in the art should understand that any improvement of the present invention, the equivalent replacement of each raw material of the product of the present invention, the addition of auxiliary components, the selection of specific methods, etc., all fall within the scope of protection and disclosure of the present invention.

Claims (10)

1. A method of extracting lithium from lithium-containing battery waste materials, characterized in that, the method may further comprise the steps: (1) mixing the pretreated lithium-containing battery waste with an aqueous oxide solution, performing a leaching reaction on the obtained raw material slurry, and obtaining the leaching slurry after the reaction; (2) adjusting the pH of the leaching slurry in step (1) to 7-13, and performing solid-liquid separation on the obtained reaction slurry to obtain a solid slag and a lithium-containing purification solution; (3) Add carbonate to the lithium-containing purification solution described in step (2), carry out the lithium sinking reaction, and separate the solid and liquid after the reaction to obtain the lithium carbonate product and the lithium sinking tail liquid, and the described lithium sinking tail liquid is adjusted to be acidic Back in the leaching reaction system of step (1). 2. The method according to claim 1, characterized in that, in step (1), the pretreatment includes mechanical crushing, ball milling, gravity separation, magnetic separation, mechanochemical treatment, organic solvent dissolution, roasting or alkali leaching Any one or a combination of at least two, preferably a combination of mechanical crushing, gravity separation, roasting and alkali leaching. 3. The method according to claim 1 or 2, characterized in that, in step (1), the lithium-containing battery waste material comprises lithium cobaltate, lithium nickelate, lithium manganate, lithium nickel cobaltate, nickel manganese acid Any one or a combination of at least two of lithium, lithium cobalt manganese oxide, nickel-cobalt-manganese ternary, nickel-cobalt-aluminum ternary, lithium-containing alloy negative electrode, lithium titanate negative electrode, or lithium-containing graphite negative electrode; Preferably, in step (1), the lithium-containing battery waste material comes from full battery powder obtained after discharging and crushing waste lithium-ion batteries, positive electrode materials obtained after dismantling waste lithium-ion batteries, disassembled waste lithium-ion batteries, etc. Any one or a combination of at least two of the negative electrode materials obtained after decomposition, the positive and negative electrode scraps generated during the lithium battery production process, or the defective product waste generated during the lithium battery production process. 4. according to the method described in any one of claim 1-3, it is characterized in that, in step (1), described oxide aqueous solution is perchlorate aqueous solution, permanganate aqueous solution, ferrate aqueous solution, fen Any one or a combination of at least two of the aqueous solution of the Fenton's reagent, the aqueous solution of the Fenton's reagent, the aqueous persulfate solution, the aqueous ozone solution or the aqueous hydrogen peroxide solution; Preferably, the aqueous ozone solution contains activated carbon. 5. The method according to any one of claims 1-4, characterized in that, in step (1), further comprising: preheating the raw material slurry before carrying out the leaching reaction; Preferably, the raw material slurry is preheated to a temperature of 25-200°C, preferably 50-150°C, more preferably 60-100°C; Preferably, in step (1), the leaching reaction is carried out in a reactor; Preferably, the reactor is an open reactor or a closed reactor, preferably a closed reactor at normal pressure; Preferably, in step (1), the leaching reaction is accompanied by stirring; Preferably, the stirring is any one or a combination of at least two of magnetic stirring, mechanical stirring or gas stirring, preferably mechanical stirring; Preferably, in step (1), the leaching reaction time is 0.5-48h, preferably 1-12h, more preferably 2-12h. 6. The method according to any one of claims 1-5, characterized in that, in step (2), the pH of the leached slurry in step (1) is adjusted to 8-11; Preferably, in step (2), the pH of the leach slurry described in step (1) is adjusted with an alkaline substance; Preferably, the alkaline substance includes any one or a combination of at least two of sodium hydroxide, potassium hydroxide, ammonia or ammonium salts; Preferably, in step (2), the solid-liquid separation is filtration separation and/or centrifugal separation, preferably filtration separation. 7. The method according to any one of claims 1-6, characterized in that, in step (3), the carbonate comprises sodium carbonate and/or potassium carbonate, preferably sodium carbonate. 8. The method according to any one of claims 1-7, characterized in that, in step (3), the temperature of the lithium precipitation reaction is above 25°C, preferably 80-100°C; Preferably, in step (3), the time of the lithium precipitation reaction is 1-10h, preferably 2-6h; Preferably, in step (3), the solid-liquid separation is filtration separation and/or centrifugal separation, preferably filtration separation. 9. The method according to any one of claims 1-8, characterized in that, in step (3), acidic substances are used to adjust the acidity and alkalinity of the lithium sinking tail liquid; Preferably, the acidic substance includes any one or a combination of at least two of sulfuric acid, hydrochloric acid, nitric acid, phosphoric acid or salts of strong acids and weak bases. 10. The method according to any one of claims 1-9, characterized in that the method comprises the following steps: (1) Mix the pretreated lithium-containing battery waste with the aqueous oxide solution to obtain a raw material slurry, preheat the raw material slurry to 60-100°C, and then place it in an airtight reactor at atmospheric pressure, and carry out under mechanical stirring conditions Leaching reaction, the reaction time is 2-12h, and the leaching slurry is obtained after the reaction; wherein, the pretreatment is a combination of mechanical crushing, gravity separation, roasting and alkali leaching; (2) adjusting the pH of the leaching slurry in step (1) to 8-11 with an alkaline substance, and filtering and separating the obtained reaction slurry to obtain a solid slag and a lithium-containing purification solution; (3) Add sodium carbonate to the lithium-containing purification solution described in step (2), carry out a lithium precipitation reaction at 80-100° C., the reaction time is 2-6 hours, and filter and separate after the reaction to obtain lithium carbonate product and lithium precipitation tail liquid , the lithium sinking tail liquid is returned to the leaching reaction system of step (1) after being adjusted to be acidic with an acidic substance.