System and method for recycling lithium from battery waste

Abstract

Embodiments described herein relate to recycling spent lithium battery materials. In some aspects, the method may include suspending a lithium source in a solvent containing an oxidation reagent to extract lithium to form an extracted lithium solution, separating the extracted lithium solution from residual solids of the lithium source, purifying the extracted lithium solution by precipitating and filtering impurities, and precipitating the lithium in the purified lithium solution to produce lithium carbonate (Li2CO3). In some embodiments, the method may further include pretreating the lithium source to improve the rate of lithium extraction. In some embodiments, the pretreatment may include a cutting or shredding step to downsize the lithium source. In some embodiments, the lithium source may include lithium-ion battery waste.

Description

[Technical Field]

[0001] Related Applications This application claims priority to and the benefit of U.S. Provisional Application No. 63 / 488,378, entitled "Systems and Methods for the Recycling of Lithium from Battery Waste," filed March 3, 2023, and U.S. Provisional Application No. 63 / 469,950, entitled "Systems and Methods for the Recycling of Lithium from Battery Waste," filed May 31, 2023, the disclosures of which are incorporated herein by reference in their entireties.

[0002] Technical Field SUMMARY OF THE INVENTION The embodiments described herein relate to systems and methods for recycling lithium from spent battery materials. [Background technology]

[0003] background Lithium-ion batteries (LIBs) are widely implemented in portable electronic devices, electric vehicles, and grid energy storage due to their low self-discharge rate, high energy and power density, and long cycle life. The LIB market will continue to grow in the future. Among cathode active materials, olivine-type lithium iron phosphate (LiFePO4, also known as LFP) and its derivatives have attracted significant attention and offer several distinct advantages over their counterparts. When used as cathode materials in LIBs, LFP and its derivatives are inherently safer, cheaper, and more durable than other cathode materials. However, the LIB manufacturing process results in the formation of unwanted by-products. The capture and utilization of these by-products can significantly improve the efficiency of the overall LIB manufacturing process. Summary of the Invention [Means for solving the problem]

[0004] overview Embodiments described herein relate to recycling spent lithium battery materials. In some aspects, the method may include suspending a lithium source in a solvent containing an oxidation reagent to extract lithium to form an extracted lithium solution, separating the extracted lithium solution from residual solids of the lithium source, purifying the extracted lithium solution by precipitating and filtering impurities, and precipitating the lithium in the purified lithium solution to produce lithium carbonate (LiCO). In some embodiments, the method may further include pretreating the lithium source to improve the rate of lithium extraction. In some embodiments, the pretreatment may include a cutting or shredding step to downsize the lithium source. In some embodiments, the lithium source may include lithium-ion battery waste. In some embodiments, the oxidation reagent may include sodium persulfate (NaSO), potassium persulfate (KSO), ammonium persulfate (NHSO), hydrogen peroxide (HO), ozone (O), and / or nitrous oxide (NO). [Brief explanation of the drawings]

[0005] [Figure 1] FIG. 1 is a flow diagram of a method for producing Li2CO3 from a lithium source, according to one embodiment.

[0006] [Figure 2] FIG. 2 is a flow diagram of a method for treating an extracted lithium solution, according to one embodiment.

[0007] [Figure 3] FIG. 3 is a flow diagram of a method for treating lithium-containing wastewater, according to one embodiment.

[0008] [Figure 4]FIG. 4 shows an X-ray diffraction (XRD) pattern of lithium carbonate produced from one embodiment compared to the XRD pattern of standard lithium carbonate.

[0009] [Figure 5] FIG. 5 shows the XRD pattern of Li-extracted iron phosphate produced from one embodiment compared to the XRD pattern of a standard iron phosphate.

[0010] [Figure 6] FIG. 6 shows the XRD pattern of lithium phosphate produced from one embodiment compared to the XRD pattern of a standard lithium phosphate. DETAILED DESCRIPTION OF THE INVENTION

[0011] Detailed Description

[0003] Embodiments described herein relate to systems and methods for recycling spent batteries. Abundant sources of lithium are important for the continuous production of new battery materials, including cathode compounds. Demand for lithium has increased globally in recent decades. Industries driving this growth include the battery materials industry, the ceramics industry, and the chemical additives industry. High-purity Li2CO3 is the most widely used lithium precursor for the production of various lithium-ion battery cathode materials. Lithium hydroxide (LiOH) is also a common lithium precursor. Extracting lithium as Li2CO3 or LiOH is an efficient and economical route for recycling low-cost LFP and its derivatives, which may include end-of-life, used, scrapped, defective LFP batteries, components, or work-in-process materials.

[0012] The embodiments described herein can develop a high-purity Li2CO3 product. The method for producing high-purity Li2CO3 processes includes suspending a lithium source and extracting lithium from the suspended lithium source. Precipitation and filtration can be used to improve the purity of the captured Li2CO3. In some embodiments, the lithium source material can be derived from an electrode (also referred to as a lithium source electrode), an electrode material, and / or scrap electrode material. In some embodiments, the lithium source can include at least one chemical composition and / or chemical structure that includes lithium. In some embodiments, the lithium source can be included in a mixture or attached to other materials that do not contain lithium. In some embodiments, the lithium source can include components in a system (e.g., full battery cells, half battery cells, battery manufacturing scrap, battery manufacturing work-in-process materials). In some embodiments, the components can be chopped, cut, crushed, or ground into powder or flakes (e.g., black chunks).

[0013] As used herein, the singular forms "a," "an," and "the" include plural referents unless the context clearly dictates otherwise. Thus, for example, the term "a member" is intended to mean a single member or a combination of members, and "a material" is intended to mean one or more materials, or combinations thereof.

[0014] The term "substantially," when used in connection with "cylindrical," "linear," and / or other geometric relationships, is intended to convey that the structure so defined is nominally cylindrical, linear, etc. As an example, a portion of a support member described as "substantially linear" is intended to convey that, while linearity of the portion is desirable, some nonlinearity may occur in the "substantially linear" portion. Such nonlinearity may result from manufacturing tolerances or other practical considerations (e.g., pressure or force exerted on the support member, etc.). Thus, a geometric structure modified by the term "substantially" includes such geometric characteristics within a tolerance of plus or minus 5% of the stated geometric structure. For example, a "substantially linear" portion is one that defines an axis or centerline that is within plus or minus 5% of a straight line.

[0015] As used herein, the terms "set" and "plurality" can refer to multiple features or a single feature having multiple portions. For example, when referring to a set of electrodes, the set of electrodes can be considered to be one electrode having multiple portions, or the set of electrodes can be considered to be multiple separate electrodes. Furthermore, for example, when referring to multiple electrochemical cells, the multiple electrochemical cells can be considered to be multiple separate electrochemical cells or one electrochemical cell having multiple portions. Thus, a set of portions or multiple portions can include multiple portions that are contiguous or discontinuous with one another. Multiple particles or multiple materials can also be fabricated from multiple items that are manufactured separately and then joined (e.g., by mixing, adhesive, or any suitable method).

[0016] FIG. 1 is a flow diagram of a method 10 for producing Li2CO3 according to one embodiment. Optional steps are indicated by dashed boxes. As shown, method 10 optionally includes pretreating the lithium source in step 11 to improve the rate of lithium extraction. Method 10 further includes suspending the lithium source in a solvent containing an oxidation reagent to extract lithium and form an extracted lithium solution in step 12. Method 10 optionally includes processing the lithium-extracted material in step 13. Method 10 further includes separating the extracted lithium from residual solids of the lithium source in step 14, purifying the extracted lithium solution by precipitation and filtration of impurities in step 15, and precipitating lithium in the purified lithium solution to produce Li2CO3 in step 16. Method 10 optionally includes isolating lithium-containing wastewater in step 17, adding one or more reagents to the lithium-containing wastewater in step 18, and further treating the lithium-containing wastewater in step 19.

[0017] Step 11 is optional and involves pretreating the lithium source to improve the rate of lithium extraction. In some embodiments, pretreatment can include mechanical, chemical, and / or thermal treatment of the lithium source. The pretreatment step can enable or improve oxidative extraction of the lithium source. A higher reaction rate leads to a higher oxidation reaction rate and therefore a faster lithium production rate. In some embodiments, pretreatment can alter the properties of the lithium source to enhance facile lithium extraction. In some embodiments, pretreatment of the lithium source can include chopping, crushing, and / or powdering the lithium source. In some embodiments, the lithium source material (e.g., battery) undergoes a cutting / shredding step to expose the internal cathode material for oxidation and extraction in step 12. In some embodiments, the lithium source material can be downsized into flakes or small pieces by methods such as chopping, cutting, grinding, or crushing. In some embodiments, the lithium source material can be downsized to the microscale / nanoscale through a powdering process. In some embodiments, the powdering process may include tamp milling, tooth milling, knife milling, ball milling, jet milling, mortar milling, and crushing.

[0018] In some embodiments, pretreatment can improve the wettability of the lithium source material before oxidative extraction in step 12. In some embodiments, the lithium source material can be vacuum-packed to enhance wettability. In some embodiments, the lithium source material can be sonicated in water before and / or during oxidative extraction in step 12. In some embodiments, the lithium source material can be heated in water to a temperature of about 100° C. or less, about 90° C. or less, about 80° C. or less, about 70° C. or less, about 60° C. or less, about 50° C. or less, or about 40° C. or less before and / or during oxidative extraction in step 12. In some embodiments, the lithium source material can be heated in air or another gas mixture (e.g., N, Ar) to a temperature of about 800° C. or less, about 700° C. or less, about 600° C. or less, about 500° C. or less, about 400° C. or less, about 300° C. or less, about 200° C. or less, or about 100° C. or less during pretreatment in step 11. This heating may serve to remove certain components, such as binders or organics, from the lithium source, which may allow for an easier oxidation process in step 12.

[0019] Step 12 involves suspending a lithium source in a solvent containing an oxidizing reagent to extract lithium, thereby forming an extracted lithium solution. In some embodiments, the lithium source may include a lithium source electrode (i.e., an electrode containing lithium). In some embodiments, the lithium source may be derived from a spent battery. In some embodiments, the lithium source electrode may include LiFePO4. In some embodiments, the lithium source electrode may include Li x M y PO4, where M is at least one transition metal, and x and y are integers. In some embodiments, the lithium source electrode may comprise a doped derivative of lithium iron phosphate (e.g., LiM x Fe 1-x PO4, or Li 1-x M xPO4, M can be one or more transition metals, and x and y are integers. In some embodiments, the lithium source electrode can include lithium cobalt oxide (LCO), lithium nickel cobalt manganese oxide (NCM or NMC), lithium nickel cobalt aluminum oxide (NCA), and / or lithium manganese oxide (LMO). In some embodiments, the lithium source electrode can include a composite containing any of the foregoing materials. In some embodiments, the lithium source electrode can be coated with any of the foregoing materials.

[0020] In some embodiments, the lithium source may include defective, scrapped, or end-of-life lithium ion batteries. In some embodiments, the lithium source may include used or end-of-life electrode sheets. In some embodiments, the lithium source may include electrode scrap material. In some embodiments, the lithium source may include used, defective, scrapped, or end-of-life lithium ion batteries. In some embodiments, the electrode scrap material may include cathode, anode, and / or battery work-in-process slurry. In some embodiments, the electrode scrap material may include other battery components or work-in-process materials, or mixtures thereof. In some embodiments, the lithium source may include crushed and / or shredded end-of-life battery material. In some embodiments, the lithium source may include a mixture of the aforementioned electrode forms.

[0021] Step 12 involves oxidation and extraction of the lithium source. This may involve oxidizing the transition metal in the lithium source with one or more oxidation reagents (using an oxidizing agent). Lithium is then extracted from the suspension as an extracted lithium solution. The extracted lithium solution may be separated from the remaining solids of the lithium source. In some embodiments, the oxidizing agent may include NaSO. NaSO has a standard redox potential of 1.96 V. The high oxidation potential of NaSO can result in shorter extraction times compared to other oxidizing substances. In some embodiments, the oxidizing agent may include KSO, (NH)SO, or any combination thereof. In some embodiments, the oxidizing agent may include HO. Hydrogen peroxide has a standard redox potential of 1.763 V. The use of HO can significantly reduce the sodium / potassium concentration solution, thereby introducing less sodium impurity into the produced lithium carbonate. When H2O2 is used as the oxidant, lithium can also be precipitated in a smaller final volume (i.e., in step 16 described below) due to the reduced concentration of sodium salts (because less liquid is needed to prevent precipitation of sodium compounds). Therefore, the yield of Li2CO3 can be increased by reducing the amount of Li2CO3 dissolved in a solution with a smaller volume. In some embodiments, the oxidant can include O3. Ozone (O3) has a standard redox potential of 2.07 V. In some embodiments, the oxidant can include NO gas. NO gas has a standard redox potential of 1.77 V. In some embodiments, the oxidant used in the extraction step can include chlorine gas, which has a standard redox potential of 1.396 V. In some embodiments, the oxidant used in the extraction step can include any combination of the aforementioned oxidants. In some embodiments, multiple oxidants can be used sequentially or at least partially in parallel.

[0022] In some embodiments, the amount of oxidizing agent used during oxidation can be at least about 0.25 times, at least about 0.5 times, at least about 0.6 times, at least about 0.7 times, at least about 0.8 times, at least about 0.9 times, at least about 1 time, at least about 1.1 times, at least about 1.25 times, at least about 1.5 times, at least about 1.75 times, at least about 2 times, at least about 2.25 times, at least about 2.5 times, at least about 2.75 times, at least about 3 times, at least about 4 times, at least about 5 times, at least about 6 times, at least about 7 times, at least about 8 times, or at least about 9 times the stoichiometric amount required to extract all the lithium from the lithium source. In some embodiments, the amount of oxidizing agent used during oxidation can be about 10 times or less, about 9 times or less, about 8 times or less, about 7 times or less, about 6 times or less, about 5 times or less, about 4 times or less, about 3 times or less, about 2.75 times or less, about 2.5 times or less, about 2.25 times or less, about 2 times or less, about 1.75 times or less, about 1.5 times or less, about 1.25 times or less, about 1.1 times or less, about 1 times or less, about 0.9 times or less, about 0.8 times or less, about 0.7 times or less, about 0.6 times or less, or about 0.5 times or less the stoichiometric amount required to extract all of the lithium from the lithium source. Combinations of the foregoing stoichiometric ratios (e.g., at least about 0.25 and about 10 or less or at least about 1 and about 5 or less) are also possible (including all values ​​and ranges therebetween). In some embodiments, the amount of oxidizing agent used during oxidation can be about 0.25 times, about 0.5 times, about 0.6 times, about 0.7 times, about 0.8 times, about 0.9 times, about 1 time, about 1.1 times, about 1.25 times, about 1.5 times, about 1.75 times, about 2 times, about 2.25 times, about 2.5 times, about 2.75 times, about 3 times, about 4 times, about 5 times, about 6 times, about 7 times, about 8 times, about 9 times, or about 10 times the stoichiometric amount needed to extract all the lithium from the lithium source.

[0023] In some embodiments, the oxidizing agent can oxidize water in the extracted lithium solution, producing oxygen gas and free protons, thereby creating an acidic environment. For example, the use of NaSO (or alternatively KSO or (NH)SO) as the oxidizing agent produces HSO. Transition metals in the lithium source may gradually dissolve in the lithium solution in an acidic environment. If the concentration of these impurity ions is high, more precipitates will form during purification in step 15 (described below), resulting in slower extraction speeds (e.g., slower filtration processes, if used in step 15). Furthermore, dissolution of transition metals in the lithium solution can degrade the structure of the lithium-extracted electrode materials, potentially adversely affecting their recyclability (e.g., recycling FePO for extraction from LFP source materials). In some embodiments, a mixture of NaSO (or alternatively KSO or (NH)SO) and HO is used for oxidative extraction. The ratio of Na2S2O8 to H2O2 can be adjusted to suit different extraction priorities.

[0024] In some embodiments, the weight:weight ratio of Na2S2O8 to H2O2 can be at least about 1:10, at least about 1:9, at least about 1:8, at least about 1:7, at least about 1:6, at least about 1:5, at least about 1:4, at least about 1:3, at least about 1:2, at least about 1:1, at least about 2:1, at least about 3:1, at least about 4:1, at least about 5:1, at least about 6:1, at least about 7:1, at least about 8:1, or at least about 9:1. In some embodiments, the weight:weight ratio of NaSO to HO can be about 10:1 or less, about 9:1 or less, about 8:1 or less, about 7:1 or less, about 6:1 or less, about 5:1 or less, about 4:1 or less, about 3:1 or less, about 2:1 or less, about 1:1 or less, about 1:2 or less, about 1:3 or less, about 1:4 or less, about 1:5 or less, about 1:6 or less, about 1:7 or less, about 1:8 or less, or about 1:9 or less. Combinations of the foregoing weight ratios are also possible (e.g., at least about 1:10 and about 10:1 or less, or at least about 1:3 and about 3:1 or less), including all values ​​and ranges therebetween. In some embodiments, the weight:weight ratio of Na2S2O8 to H2O2 can be about 1:10, about 1:9, about 1:8, about 1:7, about 1:6, about 1:5, about 1:4, about 1:3, about 1:2, about 1:1, about 2:1, about 3:1, about 4:1, about 5:1, about 6:1, about 7:1, about 8:1, about 9:1, or about 10:1.

[0025] A higher ratio of NaSO to HO can result in faster extraction rates, reducing transition metal dissolution due to a lower pH. In some embodiments, the pH of the extracted lithium solution can be controlled during the oxidative extraction process to reduce transition metal dissolution. In some embodiments, the pH of the extracted lithium solution can be monitored intermittently or continuously during the oxidative extraction. In some embodiments, alkaline and / or acidic reagents can be added to the extracted lithium solution to maintain a neutral pH. In some embodiments, the pH of the extracted lithium solution can be controlled to between about 2 and about 3, between about 3 and about 4, between about 4 and about 5, between about 5 and about 6, between about 6 and about 7, between about 7 and about 8, or between about 8 and about 9, including all values ​​and ranges therebetween.

[0026] In some embodiments, acetic acid can be used to control the pH of the extracted lithium solution between about 3.8 and about 5.8. In some embodiments, a mixture of two or more of citric acid, monopotassium phosphate, dipotassium phosphate, boric acid, acetic acid, monosodium phosphate, and disodium phosphate can be used as a pH buffer to control the pH of the extracted lithium solution over a wide range of about 3 to about 9, or even a wider range. In some embodiments, monopotassium phosphate (KH2PO4) and / or monosodium phosphate (NaH2PO4) can be used to control the pH of the extracted lithium solution between about 6.2 and about 8.2. In some embodiments, 25 parts of 0.2 mol / L K2HPO4 mixed with 23.6 parts of 0.1 mol / L sodium hydroxide and diluted to 100 parts with water can be used to control the pH to about 6.8. The rate of the oxidation reaction for some LFP derivatives may be slower than LFP. In some embodiments, LFP derivatives may contain Mn, Ni, and Co substitutions.

[0027] After the acid extraction is completed in step 12, a lithium-extracted material with lithium removed is produced. Step 13 is optional and includes further processing the lithium-extracted material. In some embodiments, the lithium-extracted material can be a lithium-deficient or delithiated compound, such as, for example, Li 1-x FePO4 (when 0 < x ≦ 1), or a similar compound corresponding to the lithium source material. In some embodiments, the lithium-extracted material can be recycled directly as a precursor for the production of unused cathode material. In some embodiments, the lithium-extracted material can be washed with water at least once, at least twice, at least three times, or at least four times to remove any soluble lithium and sodium salt impurities from the acid extraction in step 12. In some embodiments, a battery-grade FePO4 precursor can be recovered from the lithium-extracted material in step 13. In some embodiments, this precursor can be produced by separating FePO4 from other lithium-extracted materials or impurities and heating the FePO4 to remove other unwanted impurities such as binders, carbon, or other organic compounds. In some embodiments, a lithium-extracted material such as FePO4 or Li 1-x FePO4 can be heated in air or any other gaseous environment or mixture (e.g., N2, Ar) to a temperature of about 1,000 °C or less, about 900 °C or less, about 800 °C or less, about 700 °C or less, about 600 °C or less, about 500 °C or less, about 400 °C or less, about 300 °C or less, about 200 °C or less, or about 100 °C or less (including all values and ranges therebetween).

[0028] In some embodiments, the lithium-extracted material can be combined with fresh lithium source material (including material that underwent pretreatment in step 11) and subjected to oxidative extraction in step 12 to further extract any residual lithium in the source material. In some embodiments, the oxidative extraction in step 12 can be performed three or more times to increase the extraction efficiency of method 10. In some embodiments, the lithium-extracted material can be rinsed and washed with water or other solvent after the oxidative extraction in step 12 to collect any residual lithium (which may include lithium solution or lithium-containing compounds) remaining within the porous structure of the lithium-extracted electrode material. In some embodiments, the residual lithium remaining within the porous structure of the lithium-extracted electrode material can be collected by a centrifugal dryer.

[0029] Step 14 separates the lithium extracted during step 12 from residual solids or impurities of the lithium source. Step 15 involves precipitating and filtering these impurities to form a purified lithium solution. Step 14 can increase the lithium purity of the extracted lithium solution formed in step 12. Residual solids that can be removed during step 14 can include, but are not limited to, Fe, Mn, Ni, Co, Mg, Ca, P, Al, and Cu. In some embodiments, these impurities precipitate as solids at specific pH ranges and can then be removed from the extracted lithium solution. In some embodiments, adjusting the pH of the extracted lithium solution to a pH with low Fe solubility (e.g., a pH of about 8) can remove Fe impurities. In some embodiments, an oxidizing reagent (e.g., hydrogen peroxide, oxygen, nitric acid, and sodium / potassium / ammonium persulfate) can be added to the extracted lithium solution to oxidize any Fe2+ to Fe3+ to better precipitate Fe in the extracted lithium solution. In some embodiments, adjusting the pH of the extracted lithium solution to a pH of low Cu solubility (e.g., a pH of about 9) removes Cu impurities. In some embodiments, adjusting the pH of the extracted lithium solution to a pH of low Co solubility (e.g., a pH of about 10 and about 12, or between about 10 and about 12) removes Co impurities. In some embodiments, adjusting the pH of the extracted lithium solution to a pH of low Ni solubility (e.g., a pH of about 10 or higher) removes Ni impurities. In some embodiments, adjusting the pH of the extracted lithium solution to a pH of low Zn solubility (e.g., a pH of about 10) removes Zn impurities. In some embodiments, adjusting the pH of the extracted lithium solution to a pH of low Al solubility (e.g., a pH of about 6.5) removes Al impurities. In some embodiments, the aforementioned techniques for separating and removing precipitate from the extracted lithium solution include, but are not limited to, filtration, centrifugation, settling, or decanting, or any combination thereof.

[0030] The solubility of some impurities in the extracted lithium solution may increase with increasing temperature. In some embodiments, the purification in step 15 may include increasing the temperature of the environment in which the purification occurs. The solubility of some impurities may decrease with increasing temperature. In some embodiments, the purification in step 15 may include increasing the temperature of the environment in which the purification occurs. In some embodiments, more than one impurity may be removed by pH adjustment. In some embodiments, Fe, Cu, Co, Mg, Mn, Ni, and / or Zn may be precipitated and removed at a pH of about 9 to about 10, about 10 to about 11, about 11 to about 12, about 12 to about 13, or about 13 to about 14 (including all values ​​and ranges therebetween). In some embodiments, Fe, Cu, Co, Mg, Mn, Ni, and / or Zn may be precipitated and removed at a pH of at least about 9, at least about 10, at least about 11, at least about 12, or at least about 13. In some embodiments, Fe, Cu, Co, Mg, Mn, Ni, and / or Zn can be precipitated and removed at a pH of about 14 or less, about 13 or less, about 12 or less, about 11 or less, or about 10 or less. Combinations of the foregoing pH values ​​are also possible (e.g., at least about 9 and about 13 or less, or at least about 10 and about 12 or less), including all values ​​and ranges therebetween. In some embodiments, Fe, Cu, Co, Mg, Mn, Ni, and / or Zn can be precipitated and removed at a pH of about 9, about 10, about 11, about 12, or about 13.

[0031] In some embodiments, purifying the extracted lithium solution in step 15 may include adding a salt to the extracted lithium solution. In some embodiments, the salt may include Na2CO3, K2CO3, sodium oxalate, potassium oxalate, oxalic acid, or a combination thereof. In some embodiments, purifying the extracted lithium solution in step 15 may include multiple adjustments of the pH of the extracted lithium solution. In some embodiments, purifying the extracted lithium solution in step 15 may include a first pH adjustment and a second pH adjustment.

[0032] In some embodiments, the first pH adjustment can be to a pH of at least about 5, at least about 5.5, at least about 6, at least about 6.5, at least about 7, at least about 7.5, at least about 8, or at least about 8.5. In some embodiments, the first pH adjustment can be to a pH of about 9 or less, about 8.5 or less, about 8 or less, about 7.5 or less, about 7 or less, about 6.5 or less, about 5 or less, or about 5 or less. Combinations of the foregoing pH values ​​are also possible (e.g., at least about 5 and about 9 or less, or at least about 6 and about 8 or less), including all values ​​and ranges therebetween. In some embodiments, the first pH adjustment can be to a pH of about 5, about 5.5, about 6, about 6.5, about 7, about 7.5, about 8, about 8.5, or about 9.

[0033] In some embodiments, the second pH adjustment can be to a pH of at least about 8, at least about 8.5, at least about 9, at least about 9.5, at least about 10, or at least about 10.5. In some embodiments, the second pH adjustment can be to a pH of about 11 or less, about 10.5 or less, about 10 or less, about 9.5 or less, about 9 or less, or about 8.5 or less. Combinations of the foregoing pH values ​​are also possible (e.g., at least about 8 and about 11 or less, or at least about 8.5 and about 10.5 or less), including all values ​​and ranges therebetween. In some embodiments, the second pH adjustment can be to a pH of about 8, about 8.5, about 9, about 9.5, about 10, about 10.5, or about 11.

[0034] In some embodiments, step 15 may include filtering the extracted lithium solution to remove precipitated impurities. In some embodiments, step 15 may include evaporating at least a portion of the water present in the extracted lithium solution.

[0035] In some embodiments, the extracted lithium solution can be heated to a temperature of at least about 40° C., at least about 50° C., at least about 60° C., at least about 70° C., at least about 80° C., or at least about 90° C. for precipitation of Fe, Cu, Co, Mg, Mn, Ni, and / or Zn. In some embodiments, the extracted lithium solution can be heated to a temperature of not more than about 100° C., not more than about 90° C., not more than about 80° C., not more than about 70° C., not more than about 60° C., not more than about 50° C., not more than about 40° C., or not more than about 30° C. Combinations of the foregoing temperatures are also possible (e.g., at least about 40° C. and not more than about 100° C. or at least about 50° C. and not more than about 80° C.), including all values ​​and ranges therebetween. In some embodiments, the extracted lithium solution can be heated to a temperature of about 40° C., about 50° C., about 60° C., about 70° C., about 80° C., about 90° C., or about 100° C. for precipitation of Fe, Cu, Co, Mg, Mn, Ni, and / or Zn. In some embodiments, the pH of the extracted lithium solution can be adjusted with CaO, Ca(OH), NaOH, KOH, HNO, HCl, HSO, or any combination thereof.

[0036] In some embodiments, phosphorus impurities can be removed from the extracted lithium solution by adding Ca salts to the extracted lithium solution. In some embodiments, phosphorus can be precipitated as calcium phosphate (e.g., Ca3(PO4)2), which is nearly insoluble in water. The phosphorus can then be removed from the extracted lithium solution by filtration or other similar solids removal methods described herein. In some embodiments, CaCl2 and / or CaSO4 can be added to the extracted lithium solution to remove phosphate (PO4 3-) can be precipitated. In some embodiments, when the phosphate salts precipitate, the extracted lithium solution can be heated to a temperature of at least about 70°C, at least about 75°C, at least about 80°C, at least about 85°C, at least about 90°C, or at least about 95°C. In some embodiments, when the phosphate salts precipitate, the extracted lithium solution can be heated to a temperature of about 100°C or less, about 95°C or less, about 90°C or less, about 85°C or less, about 80°C or less, or about 75°C or less. Combinations of the foregoing temperatures (e.g., at least about 70°C and about 100°C or less or at least about 75°C and about 95°C or less) are also possible (including all values ​​and ranges therebetween). In some embodiments, when the phosphate salts precipitate, the extracted lithium solution can be heated to a temperature of about 70°C, about 75°C, about 80°C, about 85°C, about 90°C, about 95°C, or about 100°C.

[0037] In some embodiments, Ca salts can be added during step 12. The phosphorus extracted during step 12 forms a phosphate precipitate with the Ca salts. In embodiments, the phosphate precipitate is separated and removed by filtration, centrifugation, settling, and decanting, or a combination thereof.

[0038] In some embodiments, phosphate precipitation can occur over a period of at least about 1 hour, at least about 2 hours, at least about 3 hours, at least about 4 hours, at least about 5 hours, at least about 6 hours, at least about 7 hours, at least about 8 hours, at least about 9 hours, or at least about 10 hours. In some embodiments, phosphate precipitation can be carried out at a pH of about 8, about 9, about 10, about 11, about 12, about 13, or about 14 (including all values ​​and ranges therebetween). In some embodiments, phosphate precipitation can be removed from the extracted lithium solution by filtration, centrifugation, or settling and decanting, or a combination thereof. In some embodiments, CaCO3 can be added as a pH buffer during step 12. Dissolved calcium ions in the extracted lithium solution can precipitate phosphate when the aforementioned pH, temperature, and / or time are reached.

[0039] In some embodiments, calcium can be removed from the extracted lithium solution by adding carbonate to the extracted lithium solution. In some embodiments, Na2CO3 and / or K2CO3 can be added to the extracted lithium solution to precipitate calcium. In some embodiments, the amount of carbonate added is at least about 1.1 times, at least about 1.2 times, at least about 1.3 times, at least about 1.4 times, at least about 1.5 times, at least about 1.6 times, at least about 1.7 times, at least about 1.8 times, at least about 1.9 times, at least about 2.0 times, at least about 2.1 times, at least about 2.2 times, at least about 2.3 times, at least about 2.4 times, at least about 2.5 times, at least about 2.6 times, at least about 2.7 times, at least about 2.8 times, at least about 2.9 times, or at least about 3.0 times the stoichiometric amount of calcium to ensure efficient and / or effective removal of calcium ions. In some embodiments, excess carbonate does not react to form lithium carbonate in excess of the solubility of the extracted lithium solution. In some embodiments, calcium can be removed by adding hydroxide to the extracted lithium solution. Calcium precipitates as calcium hydroxide and can then be removed from the extracted lithium solution. In some embodiments, NaOH and / or KOH can be added to the extracted lithium solution to precipitate calcium. In some embodiments, the pH of the extracted lithium solution can be maintained at a level of at least about 9, at least about 10, at least about 11, at least about 12, at least about 13, or at least about 14 to efficiently remove calcium ions.

[0040] In some embodiments, calcium can be removed from the extracted lithium solution by adding an oxalate source to the extracted lithium solution. In some embodiments, the oxalate source can include sodium oxalate, potassium oxalate, oxalic acid, or a combination thereof. In some embodiments, the amount of oxalate added is at least about 1.1 times, at least about 1.2 times, at least about 1.3 times, at least about 1.4 times, at least about 1.5 times, at least about 1.6 times, at least about 1.7 times, at least about 1.8 times, at least about 1.9 times, at least about 2.0 times, at least about 2.1 times, at least about 2.2 times, at least about 2.3 times, at least about 2.4 times, at least about 2.5 times, at least about 2.6 times, at least about 2.7 times, at least about 2.8 times, at least about 2.9 times, or at least about 3.0 times the stoichiometric amount of calcium to ensure efficient and / or effective removal of calcium ions. In some embodiments, the pH of the extracted lithium solution can be maintained at a level of at least about 9, at least about 10, at least about 11, at least about 12, at least about 13, or at least about 14 to efficiently remove calcium ions.

[0041] In some embodiments, calcium and / or magnesium ions in the extracted lithium solution are removed by passing the extracted lithium solution through an ion exchange resin. In some embodiments, the ion exchange resin has iminodiacetic acid functional groups. In some embodiments, the ion exchange resin has aminophosphonic acid functional groups. In some embodiments, the ion exchange resin has phosphonic acid functional groups and / or sulfonic acid functional groups. In some embodiments, the ion exchange resin has aminomethylphosphonic acid functional groups. In some embodiments, more than one stage of ion exchange is performed.

[0042] In some embodiments, the extracted lithium solution can be partially evaporated to reduce the volume of the extracted lithium solution. In some embodiments, the evaporation occurs before the Ca removal step. In some embodiments, the evaporation occurs at the end of step 15 and before step 16. The smaller the solution volume, the less Li2CO3 dissolved and the higher the yield of Li2CO3. In some embodiments, the volume of the purified lithium solution can be adjusted, corrected, or otherwise monitored to ensure it is large enough to dissolve all the lithium salts at the precipitation temperature. In some embodiments, sodium and / or potassium salts can precipitate at the end of evaporation. In some embodiments, the precipitated sodium and / or potassium salts are removed by filtration, centrifugation, or settling and decanting, or a combination thereof.

[0043] In some embodiments, the lithium-extracted solution can be heated to a temperature of at least about 60°C, at least about 65°C, at least about 70°C, at least about 75°C, at least about 80°C, at least about 85°C, at least about 90°C, or at least about 95°C for calcium precipitation. In some embodiments, the lithium-extracted solution can be heated to a temperature of about 100°C or less, about 95°C or less, about 90°C or less, about 85°C or less, about 80°C or less, about 75°C or less, about 70°C or less, or about 65°C or less for calcium precipitation. Combinations of the foregoing temperature ranges (e.g., at least about 60°C and about 100°C or less or at least about 70°C and about 90°C or less) are also possible (including all values ​​and ranges therebetween). In some embodiments, the lithium-extracted solution can be heated to a temperature of about 60°C, about 65°C, about 70°C, about 75°C, about 80°C, about 85°C, about 90°C, about 95°C, or about 100°C for calcium precipitation.

[0044] In some embodiments, calcium precipitation may occur over a period of at least about 1 hour, at least about 2 hours, at least about 3 hours, at least about 4 hours, at least about 5 hours, at least about 6 hours, at least about 7 hours, at least about 8 hours, at least about 9 hours, or at least about 10 hours (including all values ​​and ranges therebetween). In some embodiments, the lithium-extracted solution may be maintained at a pH of about 7, about 8, about 9, about 10, about 11, about 12, about 13, or about 14 (including all values ​​and ranges therebetween).

[0045] In step 16, lithium is precipitated from the purified lithium solution to produce a lithium-containing compound. In some embodiments, the lithium-containing compound may include Li2CO3. The precipitated lithium-containing compound (e.g., in the form of precipitated Li2CO3) is then separated and removed from the purified lithium solution. In some embodiments, Na2CO3 and / or K2CO3 may be added to the purified lithium solution to precipitate the lithium-containing compound. In some embodiments, the purified lithium solution with the Na2CO3 and / or K2CO3 solution may be filtered to remove any insoluble impurities before adding the Na2CO3 and / or K2CO3 solution to the purified lithium solution. As the temperature of the purified lithium solution increases, the solubility of Na and / or K salts increases, while the solubility of Li2CO3 decreases.

[0046] In some embodiments, precipitation of lithium carbonate is carried out at a temperature of at least about 70°C, at least about 75°C, at least about 80°C, at least about 85°C, at least about 90°C, or at least about 95°C. In some embodiments, precipitation of lithium carbonate is carried out at a temperature of about 95°C or less, about 90°C or less, about 85°C or less, about 80°C or less, or about 75°C or less. Combinations of the foregoing temperature ranges are also possible (e.g., at least about 70°C and about 100°C or less, or at least about 75°C and about 90°C or less), including all values ​​and ranges therebetween. In some embodiments, precipitation of lithium carbonate is carried out at a temperature of about 70°C, about 75°C, about 80°C, about 85°C, about 90°C, about 95°C, or about 100°C.

[0047] In some embodiments, the purified lithium solution can be partially evaporated before or during precipitation of the lithium-containing compound to reduce the volume of the purified lithium solution. The smaller the solution volume, the less Li2CO3 dissolved and the higher the yield of Li2CO3. In some embodiments, if the purified lithium solution evaporates too much, Na and / or K salts may precipitate along with the lithium carbonate, so the volume of the purified lithium solution can be adjusted, corrected, or otherwise monitored to ensure it is large enough to dissolve all the Na and / or K salts at the precipitation temperature. In some embodiments, carbon dioxide (CO2) gas can be injected into the purified lithium solution to precipitate the dissolved lithium-containing compound. The CO2 reacts with hydroxides in the purified lithium solution to form carbonates, which then form Li2CO3, which can then precipitate from the purified lithium solution. In some embodiments, the Li2CO3 precipitate can be separated and collected by filtration, centrifugation, settling, decanting, or a combination thereof.

[0048] In some embodiments, the particle size of the precipitated lithium carbonate is controlled by adjusting the conditions during the precipitation step. In some embodiments, the conditions include the precipitation temperature, the stirring speed of the solution, whether the lithium solution is added to the NaCO and / or KCO solution or the NaCO and / or KCO solution is added to the lithium solution, and the solution mixing speed. In some embodiments, a faster stirring speed results in smaller lithium carbonate particles being precipitated. Sodium and / or potassium impurities can be encapsulated by the lithium carbonate particles. Smaller lithium carbonate particles will result in reduced Na and / or K impurities. In some embodiments, the NaCO and / or KCO solution undergoes a purification step to remove impurities. In some embodiments, the impurities include Ca and / or Mg. In some embodiments, the purification step includes adding oxalate and / or passing the purified lithium solution through an ion exchange resin.

[0049] In some embodiments, the purity of the lithium-containing compound precipitated from the purified lithium solution can be increased by further processing. In some embodiments, Na and / or K are the main impurities in the collected lithium-containing compound (e.g., Li2CO3). In some embodiments, the lithium-containing compound can be washed with water or any other suitable solvent to dissolve any residual Na and / or K salts in the lithium-containing compound. In some embodiments, the lithium-containing compound can be subjected to a washing process with water or any other suitable solvent.

[0050] In some embodiments, the water washing process can be carried out at an elevated temperature of at least about 70°C, at least about 75°C, at least about 80°C, at least about 85°C, at least about 90°C, or at least about 95°C. In some embodiments, the water washing process can be carried out at an elevated temperature of about 95°C or less, about 90°C or less, about 85°C or less, about 80°C or less, or about 75°C or less. Combinations of the foregoing temperature ranges (e.g., at least about 70°C and about 100°C or less, or at least about 75°C and about 90°C or less) are also possible (including all values ​​and ranges therebetween). In some embodiments, the water washing process can be carried out at an elevated temperature of about 70°C, about 75°C, about 80°C, about 85°C, about 90°C, about 95°C, or about 100°C. In some embodiments, the washed lithium-containing compound can be separated and collected by filtration, centrifugation, or settling and decanting, or any combination thereof. In some embodiments, the washing process can be repeated multiple times to reduce the Na and K concentrations in the lithium-containing compound.

[0051] In some embodiments, the lithium carbonate may be subjected to size reduction before or during the water washing process, hi some embodiments, the size reduction is carried out by grinding, crushing, shredding, or a combination thereof.

[0052] Step 17 is optional and involves isolating lithium-containing wastewater, which can be further processed via a wastewater recycling subsystem, described in more detail with respect to Figure 3. The wastewater recycling subsystem can be used to further extract lithium from the wastewater resulting from precipitation and from the purification in step 16. Isolation and treatment of the wastewater can increase the overall lithium extraction yield of method 10 and reduce waste.

[0053] Step 18 is optional and includes adding one or more reagents to the lithium-containing wastewater. In some embodiments, the reagent may include phosphate. In some embodiments, the reagent may include Na3PO4. In some embodiments, the reagent may include K3PO4. The addition of reagents may include additional precipitates, such as Li3PO4.

[0054] Step 19 is optional and includes further processing of the lithium-containing wastewater. In some embodiments, the further processing may include filtration to capture a precipitate. In some embodiments, step 19 may include isolating and further processing the precipitate. In some embodiments, the precipitate may include Li3PO4.

[0055] In some embodiments, method 10 can produce Li2CO3 having a purity of at least about 70% by weight, at least about 75% by weight, at least about 80% by weight, at least about 85% by weight, at least about 90% by weight, at least about 95% by weight, at least about 96% by weight, at least about 97% by weight, at least about 98% by weight, at least about 99% by weight, at least about 99.5% by weight, at least about 99.9% by weight, or at least about 99.99% by weight (including all values ​​and ranges therebetween). In some embodiments, method 10 can produce battery-grade Li2CO3.

[0056] In some embodiments, the produced Li2CO3 may contain less than about 1 wt% impurities. In some embodiments, the produced Li2CO3 may contain less than about 1 wt% sodium. In some embodiments, the produced Li2CO3 may contain less than about 0.9 wt%, less than about 0.8 wt%, less than about 0.7 wt%, less than about 0.6 wt%, less than about 0.5 wt%, less than about 0.4 wt%, less than about 0.3 wt%, less than about 0.2 wt%, less than about 0.1 wt%, less than about 0.09 wt%, less than about 0.08 wt%, less than about 0.07 wt%, less than about 0.06 wt%, less than about 0.05 wt%, less than about 0.04 wt%, less than about 0.03 wt%, less than about 0.02 wt%, or less than about 0.01 wt% sodium (including all values ​​and ranges therebetween).

[0057] In some embodiments, the produced Li2CO3 may contain less than about 1 wt.%, less than about 0.9 wt.% calcium, hi some embodiments, the produced Li2CO3 may contain less than about 0.8 wt.%, less than about 0.7 wt.%, less than about 0.6 wt.%, less than about 0.5 wt.%, less than about 0.4 wt.%, less than about 0.3 wt.%, less than about 0.2 wt.%, less than about 0.1 wt.%, less than about 0.09 wt.%, less than about 0.08 wt.%, less than about 0.07 wt.%, less than about 0.06 wt.%, less than about 0.05 wt.%, less than about 0.04 wt.%, less than about 0.03 wt.%, less than about 0.02 wt.%, or less than about 0.01 wt.% calcium (including all values ​​and ranges therebetween).

[0058] In some embodiments, the produced Li2CO3 can contain less than about 100 ppm by weight of copper. In some embodiments, the produced Li2CO3 can contain less than about 90 ppm by weight, less than about 80 ppm by weight, less than about 70 ppm by weight, less than about 60 ppm by weight, less than about 50 ppm by weight, less than about 40 ppm by weight, less than about 30 ppm by weight, less than about 20 ppm by weight, less than about 10 ppm by weight, less than about 9 ppm by weight, less than about 8 ppm by weight, less than about 7 ppm by weight, less than about 6 ppm by weight, less than about 5 ppm by weight, less than about 4 ppm by weight, less than about 3 ppm by weight, less than about 2 ppm by weight, less than about 1 ppm by weight, less than about 0.9 ppm by weight, or less than about 0.8 ppm by weight. The copper may contain less than about 0.7 ppm by weight, less than about 0.6 ppm by weight, less than about 0.5 ppm by weight, less than about 0.4 ppm by weight, less than about 0.3 ppm by weight, less than about 0.2 ppm by weight, less than about 0.1 ppm by weight, less than about 0.09 ppm by weight, less than about 0.08 ppm by weight, less than about 0.07 ppm by weight, less than about 0.06 ppm by weight, less than about 0.05 ppm by weight, less than about 0.04 ppm by weight, less than about 0.03 ppm by weight, less than about 0.02 ppm by weight, or less than about 0.01 ppm by weight (including all values ​​and ranges therebetween).

[0059] In some embodiments, the produced Li2CO3 can contain less than about 100 ppm by weight of iron. In some embodiments, the produced Li2CO3 can contain less than about 90 ppm by weight, less than about 80 ppm by weight, less than about 70 ppm by weight, less than about 60 ppm by weight, less than about 50 ppm by weight, less than about 40 ppm by weight, less than about 30 ppm by weight, less than about 20 ppm by weight, less than about 10 ppm by weight, less than about 9 ppm by weight, less than about 8 ppm by weight, less than about 7 ppm by weight, less than about 6 ppm by weight, less than about 5 ppm by weight, less than about 4 ppm by weight, less than about 3 ppm by weight, less than about 2 ppm by weight, less than about 1 ppm by weight, less than about 0.9 ppm by weight, or less than about 0.8 ppm by weight. The iron may contain less than about 0.7 ppm by weight, less than about 0.6 ppm by weight, less than about 0.5 ppm by weight, less than about 0.4 ppm by weight, less than about 0.3 ppm by weight, less than about 0.2 ppm by weight, less than about 0.1 ppm by weight, less than about 0.09 ppm by weight, less than about 0.08 ppm by weight, less than about 0.07 ppm by weight, less than about 0.06 ppm by weight, less than about 0.05 ppm by weight, less than about 0.04 ppm by weight, less than about 0.03 ppm by weight, less than about 0.02 ppm by weight, or less than about 0.01 ppm by weight (including all values ​​and ranges therebetween).

[0060] In some embodiments, the produced Li2CO3 can contain less than about 100 ppm by weight of zinc. In some embodiments, the produced Li2CO3 can contain less than about 90 ppm by weight, less than about 80 ppm by weight, less than about 70 ppm by weight, less than about 60 ppm by weight, less than about 50 ppm by weight, less than about 40 ppm by weight, less than about 30 ppm by weight, less than about 20 ppm by weight, less than about 10 ppm by weight, less than about 9 ppm by weight, less than about 8 ppm by weight, less than about 7 ppm by weight, less than about 6 ppm by weight, less than about 5 ppm by weight, less than about 4 ppm by weight, less than about 3 ppm by weight, less than about 2 ppm by weight, less than about 1 ppm by weight, less than about 0.9 ppm by weight, or less than about 0.8 ppm by weight. The zinc may contain less than about 0.7 ppm by weight, less than about 0.6 ppm by weight, less than about 0.5 ppm by weight, less than about 0.4 ppm by weight, less than about 0.3 ppm by weight, less than about 0.2 ppm by weight, less than about 0.1 ppm by weight, less than about 0.09 ppm by weight, less than about 0.08 ppm by weight, less than about 0.07 ppm by weight, less than about 0.06 ppm by weight, less than about 0.05 ppm by weight, less than about 0.04 ppm by weight, less than about 0.03 ppm by weight, less than about 0.02 ppm by weight, or less than about 0.01 ppm by weight (including all values ​​and ranges therebetween).

[0061] In some embodiments, the produced Li2CO3 can contain less than about 100 ppm by weight of aluminum. In some embodiments, the produced Li2CO3 can contain less than about 90 ppm by weight, less than about 80 ppm by weight, less than about 70 ppm by weight, less than about 60 ppm by weight, less than about 50 ppm by weight, less than about 40 ppm by weight, less than about 30 ppm by weight, less than about 20 ppm by weight, less than about 10 ppm by weight, less than about 9 ppm by weight, less than about 8 ppm by weight, less than about 7 ppm by weight, less than about 6 ppm by weight, less than about 5 ppm by weight, less than about 4 ppm by weight, less than about 3 ppm by weight, less than about 2 ppm by weight, less than about 1 ppm by weight, less than about 0.9 ppm by weight, less than about 0.8 ppm by weight, It may contain less than about 0.7 ppm by weight, less than about 0.6 ppm by weight, less than about 0.5 ppm by weight, less than about 0.4 ppm by weight, less than about 0.3 ppm by weight, less than about 0.2 ppm by weight, less than about 0.1 ppm by weight, less than about 0.09 ppm by weight, less than about 0.08 ppm by weight, less than about 0.07 ppm by weight, less than about 0.06 ppm by weight, less than about 0.05 ppm by weight, less than about 0.04 ppm by weight, less than about 0.03 ppm by weight, less than about 0.02 ppm by weight, or less than about 0.01 ppm by weight (including all values ​​and ranges therebetween).

[0062] In some embodiments, the produced Li2CO3 can contain less than about 100 ppm by weight of nickel. In some embodiments, the produced Li2CO3 can contain less than about 90 ppm by weight, less than about 80 ppm by weight, less than about 70 ppm by weight, less than about 60 ppm by weight, less than about 50 ppm by weight, less than about 40 ppm by weight, less than about 30 ppm by weight, less than about 20 ppm by weight, less than about 10 ppm by weight, less than about 9 ppm by weight, less than about 8 ppm by weight, less than about 7 ppm by weight, less than about 6 ppm by weight, less than about 5 ppm by weight, less than about 4 ppm by weight, less than about 3 ppm by weight, less than about 2 ppm by weight, less than about 1 ppm by weight, less than about 0.9 ppm by weight, or less than about 0.8 ppm by weight. , less than about 0.7 ppm by weight, less than about 0.6 ppm by weight, less than about 0.5 ppm by weight, less than about 0.4 ppm by weight, less than about 0.3 ppm by weight, less than about 0.2 ppm by weight, less than about 0.1 ppm by weight, less than about 0.09 ppm by weight, less than about 0.08 ppm by weight, less than about 0.07 ppm by weight, less than about 0.06 ppm by weight, less than about 0.05 ppm by weight, less than about 0.04 ppm by weight, less than about 0.03 ppm by weight, less than about 0.02 ppm by weight, or less than about 0.01 ppm by weight (including all values ​​and ranges therebetween). In some embodiments, method 10 can produce other lithium-containing compounds, such as LiOH, lithium phosphate (LiPO), and / or lithium chloride (LiCl).

[0063] In some embodiments, the produced Li2CO3 can contain less than about 100 ppm by weight of non-lithium alkali metals. In some embodiments, the produced Li2CO3 can contain less than about 90 ppm by weight, less than about 80 ppm by weight, less than about 70 ppm by weight, less than about 60 ppm by weight, less than about 50 ppm by weight, less than about 40 ppm by weight, less than about 30 ppm by weight, less than about 20 ppm by weight, less than about 10 ppm by weight, less than about 9 ppm by weight, less than about 8 ppm by weight, less than about 7 ppm by weight, less than about 6 ppm by weight, less than about 5 ppm by weight, less than about 4 ppm by weight, less than about 3 ppm by weight, less than about 2 ppm by weight, less than about 1 ppm by weight, less than about 0.9 ppm by weight, less than about 0.8 ppm by weight, less than about 0. The non-lithium alkali metal may contain less than 7 ppm by weight, less than about 0.6 ppm by weight, less than about 0.5 ppm by weight, less than about 0.4 ppm by weight, less than about 0.3 ppm by weight, less than about 0.2 ppm by weight, less than about 0.1 ppm by weight, less than about 0.09 ppm by weight, less than about 0.08 ppm by weight, less than about 0.07 ppm by weight, less than about 0.06 ppm by weight, less than about 0.05 ppm by weight, less than about 0.04 ppm by weight, less than about 0.03 ppm by weight, less than about 0.02 ppm by weight, or less than about 0.01 ppm by weight (including all values ​​and ranges therebetween).

[0064] In some embodiments, the produced Li2CO3 can contain less than about 100 ppm by weight of alkaline earth metal. In some embodiments, the produced Li2CO3 can contain less than about 90 ppm by weight, less than about 80 ppm by weight, less than about 70 ppm by weight, less than about 60 ppm by weight, less than about 50 ppm by weight, less than about 40 ppm by weight, less than about 30 ppm by weight, less than about 20 ppm by weight, less than about 10 ppm by weight, less than about 9 ppm by weight, less than about 8 ppm by weight, less than about 7 ppm by weight, less than about 6 ppm by weight, less than about 5 ppm by weight, less than about 4 ppm by weight, less than about 3 ppm by weight, less than about 2 ppm by weight, less than about 1 ppm by weight, less than about 0.9 ppm by weight, less than about 0.8 ppm by weight, less than about It may contain less than 0.7 ppm by weight, less than about 0.6 ppm by weight, less than about 0.5 ppm by weight, less than about 0.4 ppm by weight, less than about 0.3 ppm by weight, less than about 0.2 ppm by weight, less than about 0.1 ppm by weight, less than about 0.09 ppm by weight, less than about 0.08 ppm by weight, less than about 0.07 ppm by weight, less than about 0.06 ppm by weight, less than about 0.05 ppm by weight, less than about 0.04 ppm by weight, less than about 0.03 ppm by weight, less than about 0.02 ppm by weight, or less than about 0.01 ppm by weight (including all values ​​and ranges therebetween).

[0065] In some embodiments, the produced Li2CO3 can contain less than about 100 ppm by weight of transition metals. In some embodiments, the produced Li2CO3 can contain less than about 90 ppm by weight, less than about 80 ppm by weight, less than about 70 ppm by weight, less than about 60 ppm by weight, less than about 50 ppm by weight, less than about 40 ppm by weight, less than about 30 ppm by weight, less than about 20 ppm by weight, less than about 10 ppm by weight, less than about 9 ppm by weight, less than about 8 ppm by weight, less than about 7 ppm by weight, less than about 6 ppm by weight, less than about 5 ppm by weight, less than about 4 ppm by weight, less than about 3 ppm by weight, less than about 2 ppm by weight, less than about 1 ppm by weight, less than about 0.9 ppm by weight, or less than about 0.8 ppm by weight. , less than about 0.7 ppm by weight, less than about 0.6 ppm by weight, less than about 0.5 ppm by weight, less than about 0.4 ppm by weight, less than about 0.3 ppm by weight, less than about 0.2 ppm by weight, less than about 0.1 ppm by weight, less than about 0.09 ppm by weight, less than about 0.08 ppm by weight, less than about 0.07 ppm by weight, less than about 0.06 ppm by weight, less than about 0.05 ppm by weight, less than about 0.04 ppm by weight, less than about 0.03 ppm by weight, less than about 0.02 ppm by weight, or less than about 0.01 ppm by weight (including all values ​​and ranges therebetween).

[0066] In some embodiments, the produced Li2CO3 can contain less than about 100 ppm by weight of metalloids. In some embodiments, the produced Li2CO3 can contain less than about 90 ppm by weight, less than about 80 ppm by weight, less than about 70 ppm by weight, less than about 60 ppm by weight, less than about 50 ppm by weight, less than about 40 ppm by weight, less than about 30 ppm by weight, less than about 20 ppm by weight, less than about 10 ppm by weight, less than about 9 ppm by weight, less than about 8 ppm by weight, less than about 7 ppm by weight, less than about 6 ppm by weight, less than about 5 ppm by weight, less than about 4 ppm by weight, less than about 3 ppm by weight, less than about 2 ppm by weight, less than about 1 ppm by weight, less than about 0.9 ppm by weight, or less than about 0.8 ppm by weight. , less than about 0.7 ppm by weight, less than about 0.6 ppm by weight, less than about 0.5 ppm by weight, less than about 0.4 ppm by weight, less than about 0.3 ppm by weight, less than about 0.2 ppm by weight, less than about 0.1 ppm by weight, less than about 0.09 ppm by weight, less than about 0.08 ppm by weight, less than about 0.07 ppm by weight, less than about 0.06 ppm by weight, less than about 0.05 ppm by weight, less than about 0.04 ppm by weight, less than about 0.03 ppm by weight, less than about 0.02 ppm by weight, or less than about 0.01 ppm by weight (including all values ​​and ranges therebetween).

[0067] 2 is a flow diagram of a method 110 of treating an extracted lithium solution, according to one embodiment. As shown, the method 110 includes adding CaCl to the extracted lithium solution in step 111, adjusting the pH of the extracted lithium solution to between about 10 and about 12 in step 112, filtering the extracted lithium solution in step 113, adjusting the pH of the extracted lithium solution to between about 5 and about 9 in step 114, filtering the extracted lithium solution in step 115, optionally adding NaCO to the extracted lithium solution in step 116, optionally adjusting the pH of the extracted lithium solution to between about 8 and about 11 in step 117, and optionally filtering the extracted lithium solution in step 118 to form a purified lithium solution.

[0068] Step 111 includes adding CaCl to the extracted lithium solution. In some embodiments, the extracted lithium solution may be the same as or substantially similar to the extracted lithium solution formed in step 12, as described above with respect to FIG. 1. In some embodiments, step 111 may include adding HO to the extracted lithium solution. In some embodiments, if at least about 0.1%, at least about 1%, at least about 1%, at least about 2%, at least about 3%, at least about 4%, at least about 5%, at least about 6%, at least about 7%, at least about 8%, at least about 9%, or at least about 10% of the phosphate from the lithium source (e.g., from the LFP or LFP derivative lithium source) is leached during oxidative extraction (e.g., in step 11), CaCl can be added in an amount to at least stoichiometrically react with all of the dissolved phosphate in the extracted lithium solution.

[0069] In some embodiments, if at least about 0.1%, at least about 1%, at least about 1%, at least about 2%, at least about 3%, at least about 4%, at least about 5%, at least about 6%, at least about 7%, at least about 8%, at least about 9%, or at least about 10% of the lithium source (e.g., from the LFP or LFP-derivative lithium source) is leached as Fe(II) during oxidative extraction (e.g., in step 11), the amount of HO added during step 111 can stoichiometrically oxidize at least all of the Fe(II) in the extracted lithium solution to form Fe(III). Adding HO can oxidize the Fe(II) in solution to Fe(III).

[0070] Step 112 includes adjusting the pH of the extracted lithium solution to a value between about 10 and about 12. In some embodiments, step 112 includes adjusting the pH of the extracted lithium solution to a value between about 9 and about 10. In some embodiments, the pH of the extracted lithium solution can be adjusted to a value of about 9, about 9.5, about 10, about 10.5, about 11, about 11.5, or about 12 (including all values ​​and ranges therebetween). Adjusting the pH to such values ​​can precipitate Fe, Cu, Co, Mg, Mn, Ni, and / or Zn ions. In some embodiments, adjusting the pH to a value between about 10 and about 12 can be by the addition of NaOH and / or KOH to the extracted lithium solution. In some embodiments, phosphate ions in the extracted lithium solution can be precipitated by the addition of CaCl (e.g., in the form of Ca(PO)), or calcium ions can be precipitated by the addition of CaCl.

[0071] Step 113 includes filtering the extracted lithium solution to remove precipitated impurities. Step 114 includes adjusting the pH of the extracted lithium solution to between about 9. In some embodiments, the pH of the extracted lithium solution can be about 5, about 5.5, about 6, about 6.5, about 7, about 7.5, about 8, about 8.5, or about 9 (including all values ​​and ranges therebetween). Adjusting the pH to a value between about 5 and about 9 can aid in the precipitation of aluminum impurities. In some embodiments, the pH adjustment in step 114 can be by adding an acid to the extracted lithium solution. Step 115 includes a further repetition of filtering. Filtration in step 115 can remove aluminum impurities from the extracted lithium solution.

[0072] Step 116 is optional and includes adding Na2CO3 to the extracted lithium solution. Na2CO3 can assist in precipitating calcium ions from the extracted lithium solution. Step 117 is optional and includes adjusting the pH of the extracted lithium solution to a value between about 8 and about 11. In some embodiments, the adjustment can be to a value of about 8, about 8.5, about 9, about 9.5, about 10, about 10.5, or about 11 (including all values ​​and ranges therebetween). In some embodiments, the pH can be adjusted to a value of at least about 8, at least about 8.5, at least about 9, at least about 9.5, at least about 10, or at least about 10.5. In some embodiments, the adjustment of the pH can be facilitated by the addition of Na2CO3. The adjustment of the pH can assist in precipitating calcium ions.

[0073] Step 118 is optional and includes filtering the extracted lithium solution to form a purified lithium solution. In some embodiments, filtering in step 113, step 115, and / or step 118 may include filtration, centrifugation, settling, decanting, or a combination thereof. In some embodiments, the steps of method 110 may be performed in any order, or any of the steps may be omitted. In some embodiments, additional or repeated purification steps may be added to further increase the purity of the purified lithium solution.

[0074] In some embodiments, the pH adjustment in step 114 and the filtration in step 115 can be performed before the pH adjustment step 112 and the filtration step 113. In some embodiments, if the pH adjustment in step 114 and the filtration in step 115 are performed before the pH adjustment in step 112 and the filtration in step 113, step 117 can be omitted.

[0075] In some embodiments, method 110 may include a step of partially evaporating the extracted lithium solution. Evaporation can ensure that the final volume of the extracted lithium solution is at least an amount that can dissolve all lithium salts in the solution at any temperature between room temperature and the evaporation temperature. In some embodiments, Na and / or K salts can precipitate after evaporation. In some embodiments, the evaporation step can include removing the precipitate. In some embodiments, the precipitated Na and / or K salts are removed by filtration, centrifugation, settling and decanting, or a combination thereof. In some embodiments, the evaporation step can occur before step 111. In some embodiments, the evaporation step can occur after step 111 and before step 112. In some embodiments, the evaporation step can occur after step 113 and before step 114. In some embodiments, the evaporation step can occur after step 115 and before step 116. In some embodiments, the evaporation step can occur immediately before the ion exchange resin treatment described below.

[0076] In some embodiments, step 116 is optional. In some embodiments, steps 112 and 113 occur after steps 114 and 115, and steps 116, 117, and 118 are optional. In some embodiments, method 110 may include passing the extracted lithium solution through an ion exchange resin to remove Ca and / or Mg ions in the extracted lithium solution. In some embodiments, the ion exchange resin treatment removes Al ions in the extracted lithium solution. In some embodiments, the ion exchange resins are in their lithium form. In some embodiments, the ion exchange resins are in other cation forms, including Na and K. In some embodiments, a partial evaporation step is performed before the ion exchange resin treatment. In some embodiments, the ion exchange resin treatment occurs after steps 112 and 113. In some embodiments, steps 112 and 113 occur after steps 114 and 115, and the ion exchange resin treatment occurs after steps 112 and 113. In some embodiments, the ion exchange resin treatment occurs after step 118. In some embodiments, the ion exchange resin treatment occurs at the end of the method 110 .

[0077] 3 is a flow diagram of a method 210 for treating lithium-containing wastewater, according to one embodiment. As shown, the method 210 includes optionally washing LiCO in step 211, adding a reagent to the lithium-containing wastewater in step 212, filtering the lithium-containing wastewater to remove precipitated LiPO in step 213, filtering the extracted lithium solution to remove precipitated LiPO in step 214, adding LiPO to a CaCl solution to form a LiCl solution in step 215, filtering the precipitate in step 216, optionally adding LiCl to the extracted lithium solution in step 217, and optionally purifying the LiCO in step 218.

[0078] Step 211 is optional and includes washing the LiCO. In some embodiments, the LiCO can be precipitated from a lithium source (e.g., Method 10, as described above in connection with FIG. 1). In some embodiments, washing can be with water. Washing can improve the purity of the LiCO and dissolve or otherwise carry away precipitates. Step 212 includes adding a reagent to the lithium-containing wastewater. In some embodiments, the lithium-containing wastewater can originate from a LiCO production process (e.g., Method 10, as described above in connection with FIG. 1). In some embodiments, the lithium-containing wastewater can include precipitation wastewater (e.g., as produced in step 16, as described above in connection with FIG. 1) and refined wastewater (e.g., as produced from a washing process that further purifies the LiCO product). In some embodiments, the precipitation wastewater has been subjected to a precipitation step but still contains dissolved lithium. In some embodiments, the dissolved lithium can be in the form of LiCO. In some embodiments, the molar ratio of Na and / or K to Li in the settled wastewater can be greater than about 5:1, greater than about 6:1, greater than about 7:1, greater than about 8:1, greater than about 9:1, greater than about 10:1, greater than about 15:1, greater than about 20:1, greater than about 25:1, greater than about 30:1, or greater than about 35:1. In some embodiments, the molar ratio of Na and / or K to Li in the settled wastewater can be about 5:1 or less. In some embodiments, the molar ratio of Na and / or K to Li in the settled wastewater can be at least about 35:1.

[0079] In some embodiments, the refinery wastewater also contains dissolved lithium. In some embodiments, the dissolved lithium may be in the form of Li2CO3. In some embodiments, the molar ratio of Na and / or K to Li in the refinery wastewater may be about 4:1 or less, about 3:1 or less, about 2:1 or less, about 1:1 or less, about 0.5:1 or less, about 0.1:1 or less, or about 0.1:1 or less. In some embodiments, the molar ratio of Na and / or K to Li in the refinery wastewater may be greater than about 4:1. In some embodiments, the lithium-containing wastewater can be recycled to extract Li2CO3. This wastewater recycling process can also reduce the amount of total waste from lithium extraction and can increase the overall yield of lithium carbonate from lithium extraction.

[0080] In some embodiments, the reagent added in step 212 can include phosphate. In some embodiments, the reagent added in step 212 can include NaPO, potassium phosphate (KPO), and / or ammonium phosphate ((NH)PO). In some embodiments, NaPO can precipitate Li from the lithium-containing wastewater. In some embodiments, NaPO can react with dissolved lithium and precipitate the lithium as LiPO. In some embodiments, LiPO can be precipitated at a pH greater than about 4, greater than about 5, greater than about 6, greater than about 7, greater than about 8, greater than about 9, or greater than about 10. In some embodiments, LiPO can be precipitated at a pH greater than about 11. LiPO can be precipitated at a temperature greater than about 50°C, greater than about 60°C, greater than about 70°C, greater than about 80°C, or greater than about 90°C. In some embodiments, the amount of phosphate salt added to the lithium-containing wastewater can be at least about 1.0 times, at least about 1.5 times, at least about 2.0 times, at least about 2.5 times, or at least about 3.0 times the stoichiometric amount required to precipitate all of the lithium from the lithium-containing wastewater. In some embodiments, the phosphate salt is dissolved in water and filtered to remove any insoluble impurities before being added to the lithium-containing wastewater. In some embodiments, the dissolved Li2CO3 in the wastewater is first converted to a more soluble lithium salt by adding an acid such as HCl or H2SO4 before adding Na3PO4. In some embodiments, the dissolved Li2CO3 is converted to LiCl by the addition of HCl. In some embodiments, the dissolved Li2CO3 is converted to Li2SO4 by the addition of H2SO4.

[0081] Step 213 includes filtering the lithium-containing wastewater to remove precipitated LiPO. Step 214 includes filtering the extracted lithium solution to remove precipitated LiPO. In some embodiments, the extracted lithium solution may be derived from an oxidative extraction process (e.g., step 12 as described above in connection with FIG. 1). In some embodiments, filtering in step 213 and / or step 214 may include filtration, centrifugation, settling, decanting, or any combination thereof to isolate the LiPO. In some embodiments, the collected LiPO may be washed with water to further remove Na and / or K impurities to produce high-purity LiPO. In some embodiments, the filtration in step 213 and / or step 214 produces LiPO having a purity of at least about 95% by weight, at least about 96% by weight, at least about 97% by weight, at least about 98% by weight, at least about 99.5% by weight, at least about 99.6% by weight, at least about 99.7% by weight, at least about 99.8% by weight, or at least about 99.9% by weight (including all values ​​and ranges therebetween). In some embodiments, the high-purity LiPO can be directly reused as a precursor for the production of LFP cathode material or LFP derivative cathode materials. In some embodiments, the high-purity LiPO can be directly used in other industrial or manufacturing processes.

[0082] In step 215, LiPO is added to the CaCl solution to convert the LiPO to a soluble LiCl solution. Step 216 involves filtering the precipitate. The LiPO reacts with CaCl to form a precipitate of soluble LiCl and Ca(PO). In some embodiments, the Ca(PO) precipitate can be separated and removed by filtering, centrifugation, settling, decanting, or a combination thereof, thereby providing a solution containing LiCl. In some embodiments, the solution is heated to a temperature of at least about 70°C, at least about 75°C, at least about 80°C, at least about 85°C, at least about 90°C, or at least about 95°C to convert the LiPO to soluble LiCl. In some embodiments, the solution is heated to a temperature of about 100°C or less, about 95°C or less, about 90°C or less, about 85°C or less, about 80°C or less, or about 75°C or less to convert the LiPO to soluble LiCl. Combinations of the foregoing temperatures are also possible (e.g., at least about 70° C. and not more than about 100° C., or at least about 75° C. and not more than about 95° C.), including all values ​​and ranges therebetween. In some embodiments, the solution is heated to a temperature of about 70° C., about 75° C., about 80° C., about 85° C., about 90° C., about 95° C., or about 100° C. to convert Li3PO4 to soluble LiCl.

[0083] In some embodiments, the formation of soluble LiCl may occur over a period of at least about 1 hour, at least about 2 hours, at least about 3 hours, at least about 4 hours, at least about 5 hours, at least about 6 hours, at least about 7 hours, at least about 8 hours, at least about 9 hours, or at least about 10 hours (including all values ​​and ranges therebetween). In some embodiments, the formation of soluble LiCl may occur at a pH of about 7, about 8, about 9, about 10, about 11, about 12, about 13, or about 14 (including all values ​​and ranges therebetween). In some embodiments, there may be no detectable Na and / or K in the LiCl solution. In some embodiments, the molar ratio of Na and / or K to Li in the LiCl solution may be less than about 1.5:1, less than about 1:1, less than about 0.5:1, less than about 0.4:1, less than about 0.3:1, less than about 0.2:1, less than about 0.1:1, or less than about 0.01:1.

[0084] In some embodiments, the LiCl solution can be subjected to a calcium impurity removal step to remove residual calcium in the LiCl solution. In some embodiments, calcium can be removed by reacting and precipitating the calcium in the solution. In some embodiments, calcium is precipitated by adding at least one compound containing carbonate to the LiCl solution. The calcium precipitates as CaCO3 and is then removed from the LiCl solution. In some embodiments, Na2CO3 and / or K2CO3 can be added to the LiCl solution to precipitate calcium. In some embodiments, the amount of carbonate added to the LiCl solution can be in excess of the stoichiometric amount of calcium to ensure efficient and / or effective removal of calcium ions. In some embodiments, the excess carbonate does not react to form Li2CO3, which exceeds the solubility of the LiCl solution.

[0085] In some embodiments, calcium can be removed from a LiCl solution by adding hydroxide to the LiCl solution. The calcium can then be precipitated as Ca(OH) and then removed from the LiCl solution. In some embodiments, NaOH and / or KOH are added to the LiCl solution to precipitate calcium. In some embodiments, the pH of the LiCl solution can be maintained at a level of at least about 10, at least about 10.5, at least about 11, at least about 11.5, at least about 12, at least about 12.5, at least about 13, at least about 13.5, or at least about 14 to efficiently remove calcium ions from the LiCl solution. The LiCl solution can then undergo precipitation and purification to produce high-purity LiCO. In some embodiments, a low Na and / or K concentration in the LiCl solution can allow for more evaporation or removal of water from the solution during lithium precipitation, resulting in a lower amount of LiCO dissolution and therefore a higher yield.

[0086] In step 217, the LiCl solution is combined with the extracted lithium solution, if desired (e.g., the extracted lithium solution formed in step 11). The combined solution containing the LiCl solution and the extracted lithium solution can be further purified in step 218. Removal of impurities can include lithium precipitation and purification to produce lithium carbonate. In some embodiments, the lithium-containing wastewater produced from the combination of the LiCl solution and the extracted lithium solution can be recycled and further treated (e.g., as described above by reference).

[0087] In some embodiments, a LiCl solution can be combined with the lithium-containing wastewater prior to the addition of the reagent to the lithium-containing wastewater in step 212. In some embodiments, the LiCl can enhance the Li2CO3 purification process. In some embodiments, the remaining lithium-containing wastewater can be treated multiple times by method 210. This may allow more lithium to be extracted from the lithium-containing wastewater. In some embodiments, the purified wastewater described above with respect to step 212 can be recycled separately by evaporating the purified wastewater and precipitating the dissolved Li2CO3. In some embodiments, the final volume evaporated may be sufficient to dissolve all of the sodium salts in the purified wastewater.

[0088] In some embodiments, method 210 can produce Li2CO3 having an overall purity of at least about 70 wt%, at least about 75 wt%, at least about 80 wt%, at least about 85 wt%, at least about 90 wt%, at least about 92 wt%, at least about 95 wt%, at least about 96 wt%, at least about 97 wt%, at least about 98 wt%, or at least about 99 wt%. In some embodiments, method 210 can produce battery-grade Li2CO3 having an overall purity of at least about 99.5 wt%. In some embodiments, method 210 can produce enhanced battery-grade Li2CO3 having an overall purity of at least about 99.9 wt%. In some embodiments, method 210 can produce enhanced battery-grade Li2CO3 having an overall purity of at least about 99.99 wt%.

[0089] In some embodiments, the Li2CO3 produced can contain about 1 wt% or less, about 0.9 wt% or less, about 0.8 wt% or less, about 0.7 wt% or less, about 0.6 wt% or less, about 0.5 wt% or less, about 0.4 wt% or less, about 0.3 wt% or less, about 0.2 wt% or less, about 0.1 wt% or less, about 0.09 wt% or less, about 0.08 wt% or less, about 0.07 wt% or less, about 0.06 wt% or less, about 0.05 wt% or less, about 0.04 wt% or less, about 0.03 wt% or less, about 0.02 wt% or less, or about 0.01 wt% or less sodium.

[0090] In some embodiments, the Li2CO3 produced can contain about 1 wt% or less, about 0.9 wt% or less, about 0.8 wt% or less, about 0.7 wt% or less, about 0.6 wt% or less, about 0.5 wt% or less, about 0.4 wt% or less, about 0.3 wt% or less, about 0.2 wt% or less, about 0.1 wt% or less, about 0.09 wt% or less, about 0.08 wt% or less, about 0.07 wt% or less, about 0.06 wt% or less, about 0.05 wt% or less, about 0.04 wt% or less, about 0.03 wt% or less, about 0.02 wt% or less, or about 0.01 wt% or less calcium.

[0091] In some embodiments, the Li2CO3 produced is about 100 ppm by weight or less, about 90 ppm by weight or less, about 80 ppm by weight or less, about 70 ppm by weight or less, about 60 ppm by weight or less, about 50 ppm by weight or less, about 40 ppm by weight or less, about 30 ppm by weight or less, about 20 ppm by weight or less, about 10 ppm by weight or less, about 9 ppm by weight or less, about 8 ppm by weight or less, about 7 ppm by weight or less, about 6 ppm by weight or less, about 5 ppm by weight or less, about 4 ppm by weight or less, about 3 ppm by weight or less, about 2 ppm by weight or less, about 1 ppm by weight or less, about 0.9 ppm by weight or less, about 0.8 ppm by weight or less, about 0.7 ppm by weight or less, about 0.6 ppm by weight or less, about 0.5 ppm by weight or less, about 0.4 ppm by weight or less, about 0.3 ppm by weight or less, about 0.2 ppm by weight or less, or about 0.1 ppm by weight or less. It may contain about 0.09 ppm by weight or less, about 0.08 ppm by weight or less, about 0.07 ppm by weight or less, about 0.06 ppm by weight or less, about 0.05 ppm by weight or less, about 0.04 ppm by weight or less, about 0.03 ppm by weight or less, about 0.02 ppm by weight or less, or about 0.01 ppm by weight or less of copper.

[0092] In some embodiments, the Li2CO3 produced has a concentration of about 100 ppm by weight or less, about 90 ppm by weight or less, about 80 ppm by weight or less, about 70 ppm by weight or less, about 60 ppm by weight or less, about 50 ppm by weight or less, about 40 ppm by weight or less, about 30 ppm by weight or less, about 25 ppm by weight or less, about 20 ppm by weight or less, about 10 ppm by weight or less, about 9 ppm by weight or less, about 8 ppm by weight or less, about 7 ppm by weight or less, about 6 ppm by weight or less, about 5 ppm by weight or less, about 4 ppm by weight or less, about 3 ppm by weight or less, about 2 ppm by weight or less, about 1 ppm by weight or less, It may contain about 0.9 ppm by weight or less, about 0.8 ppm by weight or less, about 0.7 ppm by weight or less, about 0.6 ppm by weight or less, about 0.5 ppm by weight or less, about 0.4 ppm by weight or less, about 0.3 ppm by weight or less, about 0.2 ppm by weight or less, about 0.1 ppm by weight or less, about 0.09 ppm by weight or less, about 0.08 ppm by weight or less, about 0.07 ppm by weight or less, about 0.06 ppm by weight or less, about 0.05 ppm by weight or less, about 0.04 ppm by weight or less, about 0.03 ppm by weight or less, about 0.02 ppm by weight or less, or about 0.01 ppm by weight or less of iron.

[0093] In some embodiments, the Li2CO3 produced has a concentration of about 100 ppm by weight or less, about 90 ppm by weight or less, about 80 ppm by weight or less, about 70 ppm by weight or less, about 60 ppm by weight or less, about 50 ppm by weight or less, about 40 ppm by weight or less, about 30 ppm by weight or less, about 25 ppm by weight or less, about 20 ppm by weight or less, about 10 ppm by weight or less, about 9 ppm by weight or less, about 8 ppm by weight or less, about 7 ppm by weight or less, about 6 ppm by weight or less, about 5 ppm by weight or less, about 4 ppm by weight or less, about 3 ppm by weight or less, about 2 ppm by weight or less, about 1 ppm by weight or less, It may contain about 0.9 ppm or less, about 0.8 ppm or less, about 0.7 ppm or less, about 0.6 ppm or less, about 0.5 ppm or less, about 0.4 ppm or less, about 0.3 ppm or less, about 0.2 ppm or less, about 0.1 ppm or less, about 0.09 ppm or less, about 0.08 ppm or less, about 0.07 ppm or less, about 0.06 ppm or less, about 0.05 ppm or less, about 0.04 ppm or less, about 0.03 ppm or less, about 0.02 ppm or less, or about 0.01 ppm or less by weight of zinc.

[0094] In some embodiments, the Li2CO3 produced is about 100 ppm by weight or less, about 90 ppm by weight or less, about 80 ppm by weight or less, about 70 ppm by weight or less, about 60 ppm by weight or less, about 50 ppm by weight or less, about 40 ppm by weight or less, about 30 ppm by weight or less, about 25 ppm by weight or less, about 20 ppm by weight or less, about 10 ppm by weight or less, about 9 ppm by weight or less, about 8 ppm by weight or less, about 7 ppm by weight or less, about 6 ppm by weight or less, about 5 ppm by weight or less, about 4 ppm by weight or less, about 3 ppm by weight or less, about 2 ppm by weight or less, about 1 ppm by weight or less, about 0 ppm by weight or less, about 1 ... The aluminum may contain about 0.9 ppm or less, about 0.8 ppm or less, about 0.7 ppm or less, about 0.6 ppm or less, about 0.5 ppm or less, about 0.4 ppm or less, about 0.3 ppm or less, about 0.2 ppm or less, about 0.1 ppm or less, about 0.09 ppm or less, about 0.08 ppm or less, about 0.07 ppm or less, about 0.06 ppm or less, about 0.05 ppm or less, about 0.04 ppm or less, about 0.03 ppm or less, about 0.02 ppm or less, or about 0.01 ppm or less by weight.

[0095] In some embodiments, the Li2CO3 produced has a concentration of about 100 ppm by weight or less, about 90 ppm by weight or less, about 80 ppm by weight or less, about 70 ppm by weight or less, about 60 ppm by weight or less, about 50 ppm by weight or less, about 40 ppm by weight or less, about 30 ppm by weight or less, about 25 ppm by weight or less, about 20 ppm by weight or less, about 10 ppm by weight or less, about 9 ppm by weight or less, about 8 ppm by weight or less, about 7 ppm by weight or less, about 6 ppm by weight or less, about 5 ppm by weight or less, about 4 ppm by weight or less, about 3 ppm by weight or less, about 2 ppm by weight or less, about 1 ppm by weight or less, about It may contain 0.9 ppm by weight or less, about 0.8 ppm by weight or less, about 0.7 ppm by weight or less, about 0.6 ppm by weight or less, about 0.5 ppm by weight or less, about 0.4 ppm by weight or less, about 0.3 ppm by weight or less, about 0.2 ppm by weight or less, about 0.1 ppm by weight or less, about 0.09 ppm by weight or less, about 0.08 ppm by weight or less, about 0.07 ppm by weight or less, about 0.06 ppm by weight or less, about 0.05 ppm by weight or less, about 0.04 ppm by weight or less, about 0.03 ppm by weight or less, about 0.02 ppm by weight or less, or about 0.01 ppm by weight or less of nickel. [Example]

[0096] Example 1 1,000 g of LFP scrap electrode (consisting of LFP cathode, binder, and carbon) was pretreated by cutting the LFP scrap electrode into 1.5 cm LFP scrap pieces and immersing them in 2.5 L of water to form a mixture. Then, 712 g of NaSO powder was added to the mixture to carry out the oxidation extraction step. The LFP scrap pieces were stirred in the solution for 40 minutes. The oxidation reaction was observed by the temperature of the solution rising to approximately 70 °C. The extracted lithium solution was separated from the lithium-extracted LFP scrap electrode material by filtration and showed a pH of approximately 3.5. The extracted lithium solution then underwent an impurity removal process. The pH of the extracted lithium solution was adjusted to approximately 12 by adding NaOH, and the color of the solution turned green due to the presence of Fe(II). After an additional 68 g of NaSO was added to the solution to oxidize the Fe(II) to Fe(III), a yellow precipitate was observed. A clear purified lithium solution was collected after filtration. Inductively coupled plasma mass spectrometry (ICP) elemental analysis of the purified Li solution (compared to the initial extracted lithium solution before purification) is shown in Table 1. The comparison shows that most of the Al, P, Ca, Mn, and Zn impurities were removed.

[0097] Next, 300 g of Na2CO3 was completely dissolved in 1 L of water and filtered. The Na2CO3 solution was added to the purified lithium solution to carry out lithium precipitation. The precipitation reaction was carried out at 90-95 °C for 4 hours. The collected initial lithium carbonate was subjected to a series of water washes at room temperature to purify the lithium carbonate. ICP elemental analysis (Table 2) of the final lithium carbonate product indicates that the Li2CO3 has a purity of at least 99.20%. Furthermore, the X-ray diffraction (XRD) spectrum of the lithium carbonate product, shown in Figure 4, is in good agreement with the standard powder XRD spectrum of lithium carbonate.

[0098] The lithium-extracted LFP scrap electrode material after oxidative extraction underwent multiple water washes to remove any residual lithium and sodium. Although small amounts of carbon and binder may still be present in the material, the entire XRD pattern of FePO4 is detected in the lithium-extracted LFP scrap material, as shown in Figure 5. This result indicates that the disclosed oxidative extraction procedure can extract lithium while preserving the olivine structure of FePO4 in the lithium-extracted material. This recovered FePO4 can be further purified and used in LFP synthesis and / or reused in other applications.

[0099] Example 2 In another example, a mixture containing 7.5 g of a LiMn0.8Fe0.2PO4 electrode (consisting of a LiMn0.8Fe0.2PO4 cathode, binder, carbon, and Al current collector), 30 g of a LiFePO4 scrap electrode (consisting of a LiFePO4 cathode, binder, carbon, and Al current collector), and 30 g of LiFePO4 black lump powder (consisting of a LiFePO4 cathode, graphite anode, binder, carbon, and a small amount of Al / Cu impurities) was used as a mixed lithium source. The electrode was shredded into 1.5 cm thin pieces and mixed with the black lump powder in 200 ml of water. After 10 minutes of sonication, 30 g of sodium persulfate was added. The solution was heated to approximately 75 °C for 3 hours, and a clear lithium solution was collected using filtration. Next, 2 ml of 30 wt% HO and 1.1 g of CaCl2·2HO were added to the solution. The pH of the solution was adjusted to 12, and the solution was heated above 80°C for 1.5 hours. A clear solution was collected after filtration. The pH of the solution was then adjusted to 7 with HCl acid to remove Al. The solution became cloudy and returned to a clear solution after filtration through a 1-micron filter paper. The pH of the solution was then adjusted to 11, and 2 g of Na2CO3 was added. After 2 hours of mixing and subsequent filtration, the purified lithium solution was collected. Next, 13 g of Na2CO3 was completely dissolved in 40 ml of water and filtered. For lithium precipitation, the Na2CO3 solution was added to the purified lithium solution. The precipitation reaction was carried out at 90°C for 4 hours. The collected initial lithium carbonate was subjected to a series of water washes at temperatures above 80°C. ICP elemental analysis of the final lithium carbonate product showed that the Li2CO3 had a purity of at least 99.20%.

[0100] Another example involves recycling lithium from lithium-containing wastewater generated during a lithium extraction process. A solution containing approximately 7.5 g of Li2CO3 and 37.5 g of NaCl dissolved in 1,100 ml of water was used to replicate the wastewater composition. Hydrochloric acid was added to the solution to convert all of the dissolved Li2CO3 to LiCl, and the pH of the solution was then adjusted to approximately 8. Next, 28 g of Na3PO4·12H2O was added to the solution to react with the Li and precipitate Li3PO4. The solution was heated to approximately 80°C for 3 hours, and 7.0 g of Li3PO4 powder was collected. The XRD pattern of the Li3PO4 product, shown in Figure 6, is in good agreement with the standard powder XRD spectrum of Li3PO4. Next, 5.3 g of Li3PO4 powder was added to 100 ml of water along with 11 g of CaCl2·2H2O. The solution was heated to 85°C for 2 hours to convert Li3PO4 into LiCl solution, which was then filtered. The collected LiCl solution then underwent a Ca removal step. 4 g of Na2CO3 was added to the solution and stirred for 2 hours. A filtration step was performed to remove the CaCO3 precipitate. Finally, 3.6 g of Na2CO3 was completely dissolved in 20 ml of water and filtered. For lithium precipitation, Na2CO3 solution was added to the purified LiCl solution. The precipitation reaction was carried out at 90°C for 4 hours. The collected initial lithium carbonate underwent a series of water washes at temperatures above 80°C. ICP elemental analysis of the final lithium carbonate product showed that the Li2CO3 had a purity of 99.7% (Table 3).

[0101] Another example relates to recycling lithium from LFP scrap electrode material. Approximately 600 g of LFP scrap electrode (consisting of an LFP cathode, binder, and carbon) was pretreated by cutting the LFP scrap electrode into 1.5 cm LFP scrap flakes and immersing them in 1 L of water to form a mixture. Then, 475 g of NaSO powder was added to the mixture to carry out the oxidation extraction step. The LFP scrap flakes were stirred in the solution for 40 minutes. The oxidation reaction was observed by the temperature of the solution increasing to approximately 70°C. The extracted lithium solution was separated from the lithium-extracted LFP scrap electrode material by filtration and showed a pH of approximately 3.5. Next, the extracted lithium solution underwent an impurity removal process. Approximately 15 mL of HO and 32 g of CaCl were added to the extracted lithium solution and stirred for 2 hours. The pH of the extracted lithium solution was adjusted to approximately 6.5 by adding NaOH. The lithium solution was filtered to remove precipitate. The pH of the extracted lithium solution was then adjusted to about 10 and stirred for 1 hour. The lithium solution was filtered to remove precipitate. Na2CO3 was added to the solution and stirred for 1 hour. The solution was filtered to remove precipitate and then partially evaporated. The extracted lithium solution was then passed through an ion exchange resin to further remove Ca ions. A clear purified lithium solution was collected after filtration. ICP elemental analysis of the purified lithium solution (compared to the initial extracted Li solution before purification) is shown in Table 4. The comparison shows that most of the Al, P, Ca, Fe, and Zn impurities were removed.

[0102] Next, 169 g of Na2CO3 was completely dissolved in 1 L of water and filtered. The Na2CO3 solution was added to the purified lithium solution to carry out lithium precipitation. The precipitation reaction was carried out at 90-95 °C for 4 hours. The collected initial lithium carbonate was subjected to a series of water washes at temperatures of 85-95 °C to purify the lithium carbonate. The lithium carbonate was then calcined at 300-400 °C for 2-4 hours to remove moisture. ICP elemental analysis (Table 5) shows the impurity concentrations for the final lithium carbonate product. Li2CO3 has a purity of at least 99.50%. [Table 1] [Table 2] [Table 3] [Table 4] [Table 5]

[0103] Various concepts may be embodied as one or more methods, at least one example of which is provided. Operations performed as part of the methods may be ordered in any suitable manner. Thus, while illustrated as sequential operations in exemplary embodiments, embodiments may be constructed in which operations are performed in a different order than depicted, which may include performing some operations simultaneously. In other words, such features are not necessarily limited to a particular order of execution, but rather should be understood as any number of threads, processes, services, servers, and / or the like that may execute sequentially, asynchronously, concurrently, parallelly, simultaneously, synchronously, and / or the like in a manner consistent with this disclosure. Thus, some of these features may be mutually inconsistent, in that they may not simultaneously exist in a single embodiment. Similarly, some features may be applicable to one aspect of an innovation but not to others.

[0104] Furthermore, the present disclosure may include other innovations not described herein. The applicants reserve all rights in such innovations, including the right to embody such innovations and the right to file additional applications, continuations, continuations-in-part, divisional applications, and / or other similar applications. Accordingly, it should be understood that the advantages, embodiments, examples, functions, features, logic, operations, organization, structure, morphology, and / or other aspects of the present disclosure should not be considered limitations on the present disclosure as defined by the embodiments or limitations on equivalents of the embodiments. Depending on the particular needs and / or characteristics of individual and / or business users, database configurations and / or relational models, data types, data transmission and / or network frameworks, syntax structures, and / or other similar factors, various embodiments of the technology disclosed herein can be implemented in a manner that allows for great flexibility and customization, as described herein.

[0105] All definitions defined and used herein should be understood to take precedence over dictionary definitions, definitions in documents incorporated by reference, and / or ordinary meanings of the defined terms.

[0106] As used herein, in certain embodiments, the term "about" or "approximately," when preceding a numerical value, indicates a range of plus or minus 10% of the value. When a range of values ​​is provided, unless the context clearly dictates otherwise, it is understood that each value between the upper and lower limits of that range, to the tenth of the unit of the lower limit, and any other stated or intervening value within that stated range, is encompassed within the disclosure. The upper and lower limits of these smaller ranges, which may be independently included within the smaller ranges, are also encompassed within the disclosure, provided that the limit is specifically excluded within the stated range. When a stated range includes one or both of the limits, ranges excluding one or both of those included limits are also encompassed within the disclosure.

[0107] As used in the specification and embodiments, the phrase "and / or" should be understood to mean "one or both" of the elements so conjoined, i.e., elements that may be present conjunctively or disjunctively. Multiple elements listed with "and / or" should be construed in the same manner, i.e., "one or more" of the elements so conjoined. Other elements may optionally be present other than the elements specifically identified by the "and / or" clause, whether related or unrelated to those elements specifically identified. Thus, as a non-limiting example, a reference to "A and / or B," when used in conjunction with open-ended language such as "comprising," may refer in one embodiment to A only (optionally including elements other than B), in another embodiment to B only (optionally including elements other than A), in yet another embodiment to both A and B (optionally including other elements), etc.

[0108] As used herein and in the embodiments, "or" should be understood to have the same meaning as "and / or," as defined above. For example, when separating items in a list, "or" or "and / or" should be interpreted as being inclusive, i.e., including at least one (but including more than one) of an element or list of elements and, where appropriate, additional unlisted items. Only terms clearly indicating the contrary, such as "only one of" or "exactly one of," or, when used in the embodiments, "consisting of," refer to the inclusion of exactly one element of an element or list of elements. In general, the term "or" as used herein shall only be interpreted as indicating exclusive alternatives (i.e., "either / or, but not both") when preceded by exclusive terms such as "either," "one of," "only one of," or "exactly one of." "Consisting essentially of," when used in the embodiments, shall have its ordinary meaning as used in the field of patent law.

[0109] As used herein and in the embodiments, the phrase "at least one" in connection with a list of one or more elements should be understood to mean at least one element selected from any one or more of the elements in the list of elements, but not necessarily including at least one of each and every element specifically listed in the list of elements, and not excluding any combination of elements in the list of elements. This definition also allows for elements other than those specifically identified in the list of elements to which the phrase "at least one" refers, whether related or unrelated to those specifically identified elements, may optionally be present. Thus, as a non-limiting example, "at least one of A and B" (or, in other words, "at least one of A or B"; or, in other words, "at least one of A and / or B") can refer to, in one embodiment, at least one A, optionally including more than one A, with no B (optionally including elements other than B); in another embodiment, at least one B, optionally including more than one B, with no A (optionally including elements other than A); in yet another embodiment, at least one A, optionally more than one A, and at least one B, optionally more than one B (optionally including other elements), etc.

[0110] In the embodiments, as well as in the preceding specification, all transitional phrases such as "comprising," "including," "carrying," "having," "containing," "involving," "holding," "consisting of," and the like, are to be understood to be open-ended, i.e., to mean including, but not limited to. Only the transitional phrases "consisting of" and "consisting essentially of" shall be closed or semi-closed transitional phrases, respectively, as set forth in the United States Patent Office Manual of Patent Examining Procedures, Section 2111.03.

[0111] While specific embodiments of the present disclosure have been outlined above, many alternatives, modifications, and variations will be apparent to those skilled in the art. Accordingly, the embodiments described herein are intended to be illustrative, not limiting. Various changes can be made without departing from the spirit and scope of the present disclosure. Where the methods and steps described above indicate that certain events occur in a certain order, those skilled in the art with the benefit of this disclosure will recognize that the order of certain steps may be modified, and that such modifications are in accordance with variations of the present invention. Additionally, as described above, certain steps may be performed in parallel, where possible, in parallel processes, and may also be performed sequentially. While embodiments have been particularly shown and described, it will be understood that various changes in form and details may be made.

Claims

1. suspending a lithium source in a solvent containing an oxidizing reagent to extract lithium to form an extracted lithium solution; separating the extracted lithium solution from the remaining solids of the lithium source; purifying the extracted lithium solution by precipitating and filtering impurities; and Precipitating the lithium in the purified lithium solution to form Li ２ CO ３ To generate A method comprising:

2. Pretreating the lithium source to improve the rate of lithium extraction. The method of claim 1 further comprising:

3. 3. The method of claim 2, wherein the pre-treatment comprises a cutting or chopping step to downsize the lithium source.

4. The method of claim 1 , wherein the source of lithium comprises lithium ion battery waste.

5. The oxidation reagent is Na ２ S ２ O ８ , K. ２ S ２ O ８ , (NH ４ ) ２ S ２ O ８ , H ２ O ２ , O ３ , or N ２ 10. The method of claim 1, further comprising at least one of:

6. purifying the extracted lithium, CaCl ２ and H ２ O ２ to the extracted lithium solution; adjusting the pH of the extracted lithium solution to between about 10 and about 12; and filtering the extracted lithium solution to remove precipitated impurities; The method of claim 1 , comprising:

7. 7. The method of claim 6, wherein said adjusting the pH to between about 10 and about 12 is by the addition of at least one of NaOH or KOH.

8. purifying the extracted lithium solution, adjusting the pH of the extracted lithium solution to between about 5 and about 9; and filtering the extracted lithium solution to remove precipitated impurities; The method of claim 6 further comprising:

9. purifying the extracted lithium solution, Na ２ CO ３ , K. ２ CO ３ adding sodium oxalate, potassium oxalate, oxalic acid, or a combination thereof to the extracted lithium solution; adjusting the pH of the extracted lithium solution to between about 8 and about 11; and filtering the extracted lithium solution to remove precipitated impurities; The method of claim 8 further comprising:

10. purifying the extracted lithium, evaporating at least a portion of the water present in the extracted lithium solution.

10. The method of claim 9, further comprising:

11. passing the extracted lithium solution through an ion exchange resin; 10. The method of claim 9, further comprising:

12. 12. The method of claim 11, wherein the ion exchange resin contains iminodiacetic acid functional groups, aminophosphonic acid functional groups, phosphonic acid and / or sulfonic acid functional groups, or aminomethylphosphonic acid functional groups.

13. The Li ２ CO ３ To generate Na ２ CO ３ or K ２ CO ３ 10. The method of claim 1, wherein the addition of at least one of the following to the purified lithium solution occurs:

14. The Li ２ CO ３ 2. The method of claim 1 , wherein producing is by application of carbon dioxide to the purified lithium solution.

15. The Li ２ CO ３ Wash in water The method of claim 1 further comprising:

16. Lithium is precipitated, and the Li ２ CO ３ and extracting the lithium-containing wastewater from the washing of the 14. The method of claim 13, further comprising:

17. The lithium is extracted from the lithium-containing wastewater, thereby ３ P.O. ４ is generated, and said extracting Na ３ P.O. ４ or K ３ P.O. ４ adding at least one of the following to the lithium-containing wastewater; and The lithium-containing wastewater is filtered to remove precipitated Li ３ P.O. ４ To remove 17. The method of claim 16, comprising:

18. The Li ２ CO ３ is washed in water to remove the Li ３ P.O. ４ To improve the purity of 20. The method of claim 17, further comprising:

19. The lithium is extracted from the lithium-containing wastewater to produce LiCl, and the extraction Li ３ P.O. ４ CaCl ２ adding to the solution, and The CaCl ２ filtering the solution to produce a LiCl solution; 17. The method of claim 16, comprising:

20. Na ２ CO ３ , K. ２ CO ３ adding at least one of NaOH, or KOH to the LiCl solution; and filtering the LiCl solution to increase the concentration of the LiCl solution; 20. The method of claim 19, further comprising:

21. Precipitating the lithium in the LiCl solution to obtain additional Li ２ CO ３ To generate 20. The method of claim 19, further comprising:

22. Precipitating the lithium in the LiCl solution to obtain additional Li ２ CO ３ To generate Na ２ CO ３ or K ２ CO ３ 22. The method of claim 21 , wherein the LiCl solution is at least one of:

23. Precipitating the lithium in the LiCl solution to obtain additional Li ２ CO ３ 22. The method of claim 21 , wherein generating is by adding carbon dioxide to the LiCl solution.

24. The additional Li ２ CO ３ in water to remove the additional Li ２ CO ３ Further purifying 22. The method of claim 21 further comprising:

25. The additional Li ２ CO ３ Extracting additional lithium from wastewater produced from washing 25. The method of claim 24, further comprising:

26. The LiCl solution is fed to the extracted lithium solution to add more Li ２ CO ３ To generate 20. The method of claim 19, further comprising:

27. combining said LiCl solution with an additional lithium source; 27. The method of claim 26, further comprising:

28. CaCl ２ and H ２ O ２ to the extracted lithium solution; adjusting the pH of the extracted lithium solution to between about 9 and about 12; filtering the extracted lithium solution a first time; adjusting the pH of the extracted lithium solution to between about 5 and about 9; and filtering the extracted lithium solution a second time. A method comprising:

29. Na ２ CO ３ adding to the extracted lithium solution 30. The method of claim 28, further comprising:

30. adjusting the pH of the extracted lithium solution to between about 8 and about 11; 30. The method of claim 28, further comprising:

31. filtering the extracted lithium solution a third time to form a purified lithium solution.

31. The method of claim 30, further comprising:

32. The reagent is added to the lithium-containing wastewater to ３ P.O. ４ forming a precipitate, The lithium-containing wastewater is filtered to extract a first amount of Li ３ P.O. ４ removing the precipitate; The extracted lithium solution is filtered to obtain a second amount of Li ３ P.O. ４ removing the precipitate; The first amount of Li ３ P.O. ４ precipitate and the second amount of Li ３ P.O. ４ The precipitate was treated with CaCl ２ adding to the solution to form a LiCl solution; and filtering the precipitate from the LiCl solution. A method comprising:

33. Li ２ CO ３ to form an extracted lithium solution.

33. The method of claim 32, further comprising:

34. adding LiCl to the extracted lithium solution; 34. The method of claim 33, further comprising:

35. The Li ２ CO ３ To refine 34. The method of claim 33, further comprising:

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