System and method of recycling of aluminium-air battery and recovery of al(OH) 3 and KOH electrolyte

Abstract

A method and system for recycling aluminium-air batteries and recovering valuable components, aluminium trihydroxide (ATH) and potassium hydroxide (KOH) electrolyte includes selective precipitation and electrodialysis techniques to efficiently recover ATH and KOH with high purity. The process begins with a feed collection unit (102) receiving a 5 recycled solution mixture from batteries, which is then filtered by a filtration unit (104) to filter out sustemded particles of ATH and impurites. The filtered solution is subjected to precipitation in a precipitation unit (108) to precipitate ATH, and thereafter to electrodialysis in an electrodialysis unit (114) to convert the potassium salt solution remaining after the precipitation to KOH electrolyte and an acid. The electrodialysis is carried out using ion-0 selective membranes and acid acid obtained from the electrodialysis unit (114) in the precipitation unit (108).

Description

SYSTEM AND METHOD OF RECYCLING OF ALUMINIUM-AIR BATTERY AND RECOVERY OF AL(OH)3AND KOH ELECTROLYTETECHNICAL FIELD

[0001] The present disclosure relates, in general, to a process for recycling aluminium air batteries, and more specifically, to a system and method for separating and recovering aluminium trihydroxide (ATH) and potassium hydroxide (KOH) electrolyte from a mixture of metal hydroxides, utilizing selective precipitation and electrodialysis techniques.BACKGROUND

[0002] Aluminium-air batteries exhibit a significantly higher energy density compared to conventional batteries, such as lead-acid or lithium-ion batteries, making them particularly suitable for applications in electric vehicles, energy storage systems (ESS), and portable electronic devices. This high energy density offers a lightweight, high-capacity energy storage solution for electric vehicles and renewable energy systems, thereby driving interest in aluminium-air batteries. A key advantage of aluminium-air batteries is their recyclability, as aluminum can be readily recycled in the form of ATH without degradation of its properties, and recovered KOH contributes to a more sustainable lifecycle for the battery.

[0003] Recovery of aluminum from aluminum-air (Al-air) batteries involves a mechanical recharging process where the aluminum oxide byproduct is recycled to create new aluminum anodes. Unlike lithium-ion batteries. Al-air batteries are primary cells, so they are not rechargeable in the traditional sense; instead, the depleted aluminum is replaced with a new one made from the recycled byproduct. The overall process is environmentally friendly, as it leverages aluminum's near- 100% recyclability to reuse it as an energy carrier.

[0004] Despite these advantages, aluminum-air batteries face certain challenges, including issues related to the management of the aluminum oxide byproduct, limited rechargeability, and the need for further optimization to enhance their performance for commercial applications. Recycling aluminum-air batteries is essential to support a circular economy model, which emphasizes sustainable resource usage and waste reduction through recycling and reuse. However, several challenges must be addressed to fully integrate aluminum-air batteries into this framework. Aluminum-air battery recycling is complicated by factors such as the complex composition of the materials, the difficulty of recovering pure potassium hydroxide (KOH), and the necessity for efficient separation techniques. Contamination and energy-intensive processes can hinder the recovery of pure KOH, whilematerial losses may reduce recycling efficiency and increase operational costs. To improve recycling efficiency and maximize the benefits of aluminum-air battery technology, ongoing research, advancements in recycling technology, and public engagement are needed to support sustainable recycling practices. These developments are critical for optimizing aluminum-air battery technology and enhancing its applicability in a circular economy.

[0005] Therefore, it is desired to overcome the drawbacks, shortcomings, and limitations associated with existing solutions, and develop a scalable and viable method for recycling aluminum air batteries through selective precipitation and electrodialysis, thereby refining aluminum trihydroxide (ATH) and potassium hydroxide (KOH). ATH can further be applied in water treatment and manufacturing industry. On the other hand potassium hydroxide (KOH) is reused as electrolyte in battery applications.OBJECTS OF THE PRESENT DISCLOSURE

[0006] An object of the present disclosure is to provide a system for recycling aluminum-air batteries that enables efficient separation and recovery of aluminum trihydroxide (ATH) and potassium hydroxide (KOH) electrolyte.

[0007] Another object of the present disclosure is to provide a system that utilizes selective precipitation and electrodialysis techniques to achieve high-purity recovery of ATH and KOH for reuse in battery applications.

[0008] Another object of the present disclosure is to provide a system that minimizes waste generation through a closed-loop process, where residual materials are recycled and reused in aluminum -air battery production and other technical fields.

[0009] Another object of the present disclosure is to provide a system that is scalable for industrial use, enabling large-scale recycling of aluminum-air batteries with optimized material efficiency and resource utilization.

[0010] Yet another object of the present disclosure is to provide a system that reduces environmental impact by recovering valuable battery components and minimizing the release of impurities and waste byproducts.SUMMARY

[0011] The present disclosure relates in general, to a process for recycling aluminum air batteries, and more specifically, to a method for separating and recovering aluminum trihydroxide (ATH) and potassium hydroxide (KOH) electrolyte from a mixture of metal hydroxides, utilizing selective precipitation and electrodialysis techniques. The mainobjective of the present disclosure is to overcome the drawbacks, limitations, and shortcomings of the existing system and solution, by providing a process for recycling aluminum-air batteries or cells and recovering aluminum trihydroxide (ATH) and potassium hydroxide (KOH) electrolyte. The process comprises a method for separating aluminum trihydroxide (ATH) and recovering KOH electrolyte from a mixture of metal hydroxides containing aluminum (Al), potassium (K), magnesium (Mg), and tin (Sn). The separation process is divided into two stages selectively precipitating aluminum trihydroxide (ATH) through selective precipitation technique and recovering KOH electrolyte using an electrodialysis methodology.

[0012] In an aspect, the proposed method for recycling Aluminum-Air batteries includes the the steps of: (i) precipitating, at a precipitation unit, from a solution recovered from a feedstock from the Aluminum-Air batteries, aluminum trihydroxide in fine white powder form. The solution remaining after precipitation is a potassium salt solution; and (ii) peforming electrodialysis, in an electrodialysis unit, on the potassium salt solution to convert the potassium salt solution to KOH electrolyte and an acid. In an aspect, the electrodialysis is carried out using ion-selective membranes.

[0013] In an aspect, the method includes using the acid obtained from the electrodialysis unit in the precipitation unit.

[0014] In an aspect, the method includes: filtering, using a filtration unit, the feedstock from the Aluminum-Air batteries to remove suspended particles of aluminum trihydroxide and impurities to recover the solution.

[0015] In an aspect, the method includes: washing and drying, using a first washing and drying unit (also referred to simply as washing and drying unit, herein), the removed suspended particles of aluminum trihydroxide and impurities to remove soluble impurities and collect the aluminum trihydroxide in a dry powder form.

[0016] In an aspect, the method includes: purifying, using a second washing and drying unit (also referred to as ATH washing and drying unit, herein), the precipitated aluminum trihydroxide from the precipitation unit to get aluminum trihydroxide in a high-purity powder form.

[0017] An aspect of the present disclosure relates to a system for recycling Aluminum- Air batteries, the system including a precipitation unit for precipitating aluminum trihydroxide in fine white powder form a solution recovered from a feedstock from the Aluminum-Air batteries, such that solution remaining after precipitation is a potassium salt solution; and an electrodialysis unit for performing electrolysis on the potassium salt solutionto convert the potassium salt solution to KOH electrolyte and an acid. In an aspect, the electrodialysis unit includes ion-selective membranes.

[0018] In an aspect, the system uses the acid obtained from the electrodialysis unit in the precipitation unit.

[0019] In an aspect, the system further includes a filtration unit for filtering the feedstock from the Aluminum-Air batteries to filter out suspended particles of aluminum trihydroxide and impurities to recover the solution.

[0020] In an aspect, the system further includes a first washing and drying unit for washing and drying the filtered out suspended particles of aluminum trihydroxide and impurities to remove soluble impurities and collect the aluminum trihydroxide in a dry powder form.

[0021] In an aspect, the system further includes a second washing and drying unit to purify the precipitated aluminium trihydroxide from the precipitation unit to get aluminium trihydroxide in a high-purity powder form.

[0022] In an aspect, the system further includes a first washing and drying unit to remove suspended particles of aluminum trihydroxide and impurities to remove soluble impurities and collect the aluminium trihydroxide in a dry powder form.

[0023] The system (100) as claimed in claim 7, comprising the step of: purifying, using a second washing and drying unit (112), the precipitated aluminium trihydroxide from the precipitation unit (108) to get aluminium trihydroxide in a high-purity powder form.

[0024] Various objects, features, aspects, and advantages of the inventive subject matter will become more apparent from the following detailed description of preferred embodiments, along with the accompanying drawing figures in which like numerals represent like components.BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The following drawings form part of the present specification and are included to further illustrate aspects of the present disclosure. The disclosure may be better understood by reference to the drawings in combination with the detailed description of the specific embodiments presented herein.

[0026] FIG. 1 illustrates an exemplary block diagram for the proposed system for recycling aluminium-air batteries and recovering aluminium trihydroxide (ATH) and potassium hydroxide (KOH) electrolyte, in accordance with an embodiment of the present disclosure.

[0027] FIG. 2 illustrates an exemplary method flow diagram for the proposed a method for recycling aluminium-air batteries and recovering aluminium trihydroxide (ATH) and potassium hydroxide (KOH) electrolyte, in accordance with an embodiment of the present disclosure.DETAILED DESCRIPTION

[0028] The following is a detailed description of embodiments of the disclosure depicted in the accompanying drawings. The embodiments are in such detail as to clearly communicate the disclosure. If the specification states a component or feature “may”, “can”, “could”, or “might” be included or have a characteristic, that particular component or feature is not required to be included or have the characteristic.

[0029] As used in the description herein and throughout the claims that follow, the meaning of “a,” “an,” and “the” includes plural reference unless the context clearly dictates otherwise. Also, as used in the description herein, the meaning of “in” includes “in” and “on” unless the context clearly dictates otherwise.

[0030] The present disclosure relates to a comprehensive process for aluminium-air battery recycling, specifically addressing the separation and purification of aluminium trihydroxide (ATH) and potassium hydroxide (KOH) electrolyte. Accordingly, the disclosed method facilitates the following advancements.

[0031] Refining aluminium trihydroxide (ATH): The refinement of aluminium trihydroxide (ATH) from aluminium-air batteries enhances recycling efficiency and quality, promoting sustainability and resource recovery within battery recycling processes, thus supporting a circular economy and contributing to a more sustainable lifecycle for batteries. This disclosure includes a surface charge neutrality-based precipitation method developed to recover ATH with minimal material loss and improved purity.

[0032] Recovery of KOH electrolyte: The recovery of potassium hydroxide (KOH) from aluminium-air battery recycling is achieved through an electrodialysis process, providing an effective solution for sustainable resource recovery. By utilizing the advantages of electrodialysis, including high efficiency and low energy consumption, this green recycling process is optimized to yield high-purity KOH, thereby contributing to resource conservation and sustainable recycling practices.

[0033] The present disclosure provides a system for recycling aluminium-air batteries and recovering aluminium trihydroxide (ATH) and potassium hydroxide (KOH) electrolyte. The system includes a feed collection unit is configured to receive a feedstock comprising arecycled solution mixture from one or more batteries, wherein the feedstock includes a mixture of suspended aluminium trihydroxide (ATH), potassium hydroxide (KOH) electrolyte, and dissolved impurities. The filtration unit is operatively coupled to the feed collection unit and configured to receive the recycled solution mixture. The filtration unit is further configured to separate suspended particles, including ATH, from the KOH solution along with dissolved impurities. The washing and drying unit is configured to remove soluble impurities from the recovered ATH and collect the recovered ATH in a dry powder form.

[0034] The ATH precipitation unit is configured to receive the clear solution following the removal of suspended solids. The selective precipitation unit for ATH is operatively connected to the acid mixing unit and configured to receive a mixed solution of ATH and KOH from the filtration unit and the acid mixing unit, wherein the ATH precipitation unit precipitates crude ATH, extracted as a white powder. The ATH washing and drying unit is configured to receive the crude ATH powder from the ATH precipitation unit and to remove residual impurities, collecting the recovered ATH as a high-purity dry powder.

[0035] The electrodialysis unit is operatively connected to the ATH precipitation unit and configured to receive a potassium salt solution from the ATH precipitation unit and to convert this solution into acid and electrolyte-grade KOH. The electrodialysis unit contains ion-selective membranes, electrodes, receiving tanks, and collection tanks and is operatively connected to an acid collection unit and a KOH collection tank. The acid collection unit is configured to receive acid generated during the electrodialysis process from the electrodialysis unit and is operatively connected to the acid mixing unit for use in the ATH precipitation process. The present disclosure can be described in enabling detail in the following examples, which may represent more than one embodiment of the present disclosure.

[0036] The advantages achieved by the system of the present disclosure can be clear from the embodiments provided herein. The method for efficiently recovering aluminium trihydroxide (ATH) from aluminium-air batteries, thereby enhancing the recycling process and obtaining ATH with high purity. The method also provides for the recovery of high- purity potassium hydroxide (KOH) electrolyte, enabling its direct reuse in new aluminium-air batteries and supporting sustainability in the recycling process. Furthermore, the method operates within a closed-loop system that recycles residues from the purification step back into battery production, minimizing waste and reducing environmental impact. The disclosed method is scalable for industrial applications, making it feasible to implement on a larger scale within the aluminium-air battery recycling industry. Additionally, the method ensuresimproved material efficiency, reducing the loss of valuable materials and promoting the efficient use of resources within the recycling process.

[0037] The description of terms and features related to the present disclosure shall be clear from the embodiments that are illustrated and described; however, the invention is not limited to these embodiments only. Numerous modifications, changes, variations, substitutions, and equivalents of the embodiments are possible within the scope of the present disclosure. Additionally, the invention can include other embodiments that are within the scope of the claims but are not described in detail with respect to the following description.

[0038] FIG. 1 illustrates an exemplary view of a system for recycling aluminium-air batteries and recovering aluminium trihydroxide (ATH) and potassium hydroxide (KOH) electrolyte, in accordance with an embodiment of the present disclosure.

[0039] Referring to FIG. 1, a system 100 for recycling aluminium-air batteries and recovering aluminium trihydroxide (ATH) and potassium hydroxide (KOH) electrolyte is disclosed. The disclosed process employs selective precipitation and electrodialysis methods for the respective recovery of ATH and KOH electrolytes. The system 100 includes feed collection unit 102, filtration unit 104, washing and drying unit (also referred to as first washing and drying unit, herein) 106, ATH precipitation unit 108 (also referred to simply as precipitation unit, herein), acid mixing unit 110, ATH washing and drying unit (also referred to as second washing and drying unit, herein) 112, electrodialysis unit 114, acid collection tank 116, and KOH collection tank.

[0040] The feed collection unit 102 is configured to receive a feedstock consisting of a recycled solution mixture from one or more batteries. The feedstock is a blend of suspended ATH, KOH electrolyte, and dissolved impurities, which serves as the initial material for processing and separation. The filtration unit 104 is coupled to the feed collection unit 102 and configured to receive the recycled solution mixture. The filtration unit 104 is responsible for separating suspended particles, including ATH, from the KOH solution along with impurities, enabling further purification and recovery processes.

[0041] The washing and drying unit 106 is configured to receive the separated ATH from the filtration unit 104. The washing and drying unit 106 removes any soluble impurities within the recovered ATH and collects it in a dry powder form, suitable for further processing or reuse. The ATH precipitation unit 108 is configured to receive the clear solution after the suspended solid removal step. The ATH precipitation unit 108 directs the clarified solution to subsequent processing stages to enable the selective recovery of ATH. The ATH precipitation unit 108 operatively connected with the acid mixing unit 110. The ATH precipitation unit108 receives a mixed solution of ATH and KOH from the filtration unit 104 and acid mixing unit 110. Within this unit, ATH is selectively precipitated using a surface charge neutralitybased method, resulting in crude ATH extracted as a fine white powder.

[0042] The ATH washing and drying unit 112 is configured to receive the crude white powder from the ATH precipitation unit 108. The ATH washing and drying unit 112 is configured to remove any residual impurities and dry the ATH, collecting it as a high-purity dry powder form ready for reuse or further applications.

[0043] The electrodialysis unit 114 is connected to the ATH precipitation unit 108. The electrodialysis unit 114 receives the salt solution of potassium from the ATH precipitation unitl08. The electrodialysis unit 114 contains ion-selective membranes, electrodes, receiving tanks, and collection tanks, and is configured to convert the potassium salt solution into high- purity KOH electrolyte and acid. This process minimizes energy consumption and maximizes recovery efficiency. The electrodialysis unit 114 is also operatively linked with the acid collection tank 116 and the KOH collection tank 118.

[0044] The acid collection tank 116 is configured to receive acid generated during the electrodialysis process from the electrodialysis unit 114. The acid collection tank 116 supplies the acid to the acid mixing unit 110 for use in the ATH precipitation process, enabling a closed-loop system that minimizes waste and maximizes resource utilization. The KOH collection tank 118 is connected to the electrodialysis unit 114 and configured to store high-purity KOH electrolyte recovered during the electrodialysis process. This recovered KOH, with purity exceeding 99.7%, can be directly reused in new aluminium-air batteries, contributing to the sustainability and cost-effectiveness of the recycling process. The recovered ATH exhibits a purity exceeding 99.5%, while the KOH electrolyte attains a purity exceeding 99.7%, enabling its direct reuse in new aluminium-air batteries.

[0045] The present disclosure could be applied in a recycling facility specializing in the sustainable processing of aluminium-air batteries used in electric vehicles. As electric vehicles become more popular, aluminium-air batteries are being increasingly deployed due to their high energy density. However, once the batteries reach the end of their useful life, they pose disposal and recycling challenges due to their chemical components. A recycling plant could utilize the disclosed system to process used aluminium-air batteries by employing selective precipitation and electrodialysis to recover aluminium trihydroxide (ATH) and potassium hydroxide (KOH) with high purity. The recovered ATH can be reused in producing new aluminium-air batteries or for other industrial applications where ATH isvaluable. Similarly, the recovered KOH, with its high purity level of over 99.7%, can be directly reused as an electrolyte in new batteries, thereby reducing the need for fresh KOH.

[0046] This closed-loop recycling process minimizes waste and environmental impact by allowing both ATH and KOH to be reused. Additionally, the scalability of the process makes it viable for large-scale industrial applications, helping battery manufacturers reduce production costs, ensure resource efficiency, and contribute to a sustainable lifecycle for aluminium-air batteries.

[0047] The system 100 for recycling aluminium-air batteries and recovering valuable components, wherein the system 100 includes efficient recovery of aluminium trihydroxide (ATH), is achieved through selective precipitation, enabling high-purity recovery and improved material utilization. Efficient recovery of potassium hydroxide (KOH) electrolyte, a critical component of aluminium-air batteries, through an electrodialysis process, providing high-purity KOH suitable for direct reuse in battery applications.

[0048] Implementation of a closed-loop system, wherein residual materials from the purification process are recycled and reused in battery production, minimizes waste generation and reduces environmental impact. Scalability of the process, enabling industrialscale applications in aluminium-air battery recycling, makes the proposed method and system suitable for large-scale industry adoption. Enhanced material efficiency, wherein valuable materials are retained throughout the process, ensuring high-quality outputs and optimizing resource utilization. A competitive advantage for the aluminium-air battery industry due to the process's efficiency, cost-effectiveness, and sustainable approach to battery recycling.

[0049] Thus, the present invention overcomes the drawbacks, shortcomings, and limitations associated with existing solutions, and provides a system and method for efficient recovery of aluminium trihydroxide (ATH) from aluminium-air batteries, thereby enhancing the recycling process and obtaining ATH with high purity. The method also provides for the recovery of high-purity potassium hydroxide (KOH) electrolyte, enabling its direct reuse in new aluminium-air batteries and supporting sustainability in the recycling process. Furthermore, the method operates within a closed-loop system that recycles residues from the purification step back into battery production, minimizing waste and reducing environmental impact. The disclosed method is scalable for industrial applications, making it feasible to implement on a larger scale within the aluminium-air battery recycling industry. Additionally, the method ensures improved material efficiency, reducing the loss of valuable materials and promoting the efficient use of resources within the recycling process.

[0050] FIG. 2 illustrates an exemplary view of a method for recycling aluminium-air batteries and recovering aluminium trihydroxide (ATH) and potassium hydroxide (KOH) electrolyte, in accordance with an embodiment of the present disclosure.

[0051] Referring to FIG. 2, the method 200 for recycling aluminium-air batteries and recovering aluminium trihydroxide (ATH) and potassium hydroxide (KOH) electrolyte, the method incudes at block 202, the feed collection unit configured to receive a feedstock consisting of a recycled solution mixture from one or more batteries, the feedstock including suspended ATH, KOH electrolyte, and dissolved impurities.

[0052] At block 204, the filtration unit coupled to the feed collection unit and configured to separate suspended particles, including ATH, from the KOH solution containing dissolved impurities. At block 206, the washing and drying unit is configured to receive the separated ATH from the filtration unit, the washing and drying unit being adapted to remove soluble impurities and collect ATH in a dry powder form.

[0053] At block 208, the ATH precipitation unit is operatively connected to the acid mixing unit and configured to receive a clear solution after the suspended solid removal step, wherein the ATH precipitation unit selectively precipitates ATH as a fine white powder. At block 210, the ATH washing and drying unit is configured to receive crude ATH from the ATH precipitation unit, the ATH washing and drying unit is adapted to remove residual impurities and dry ATH to a high-purity powder form.

[0054] At block 212, the electrodialysis unit connected to the ATH precipitation unit, the electrodialysis unit containing ion-selective membranes, electrodes, receiving tanks, and collection tanks, the electrodialysis unit configured to convert a potassium salt solution into KOH electrolyte and acid. At block 214, the acid collection tank connected to the electrodialysis unit and configured to receive acid generated during electrodialysis, the acid collection tank supplying acid to the acid mixing unit and at block 216, the KOH collection tank connected to the electrodialysis unit, the KOH collection tank configured to store high- purity KOH electrolyte recovered during the electrodialysis process for direct reuse in aluminium-air batteries.

[0055] In an implementation of an embodiment, when EV batteries reach the end of their life cycles, they are often difficult to dispose of due to their electrolyte and metal content. This facility could use the disclosed system to process these batteries, specifically targeting aluminium trihydroxide (ATH) and potassium hydroxide (KOH) electrolyte for recovery. The facility receives multiple end-of-life aluminium-air batteries, which are dismantled to extract a recycled solution mixture containing suspended ATH, KOHelectrolyte, and dissolved impurities. This mixture is collected in the feed collection unit 102 as the primary input for the recycling process. The recycled solution is then directed to the fdtration unit 104, where the system separates suspended ATH particles from the KOH solution. This step removes most impurities, preparing the ATH for further purification.

[0056] The separated ATH moves to the washing and drying unit 106, which removes any soluble impurities, drying the ATH into a pure, reusable powder. This ATH can now be used either in new battery manufacturing or other industrial applications where ATH is required. The clarified KOH solution moves to the ATH precipitation unit 108 and the acid mixing unit 110, where ATH is selectively precipitated using a surface charge neutrality method. The resulting ATH is collected as a fine white powder. The crude ATH is then purified in the ATH washing and drying unit 112 where it is dried into a high-purity powder ready for reuse.

[0057] The remaining potassium salt solution is transferred to the electrodialysis unit 114, where it is processed using ion-selective membranes and electrodes to recover high- purity KOH electrolyte and acid. This step is highly energy-efficient, allowing the facility to maximize recovery of the KOH electrolyte for reuse in new batteries. The recovered acid is stored in the acid collection tank 116 and is re-circulated into the ATH precipitation process, creating a closed-loop system. The KOH collection tank 118 stores the high-purity KOH electrolyte, which can then be reused directly in new battery manufacturing.

[0058] It will be apparent to those skilled in the art that the system 100 of the disclosure may be provided using some or all of the mentioned features and components without departing from the scope of the present disclosure. While various embodiments of the present disclosure have been illustrated and described herein, it will be clear that the disclosure is not limited to these embodiments only. Numerous modifications, changes, variations, substitutions, and equivalents will be apparent to those skilled in the art, without departing from the spirit and scope of the disclosure, as described in the claims.ADVANTAGES OF THE PRESENT INVENTION

[0059] The present disclosure provides a method for efficiently recovering aluminium trihydroxide (ATH) from aluminium-air batteries, enhancing the recycling process by obtaining ATH with high purity.

[0060] The present disclosure provides a green method for recovering high-purity potassium hydroxide (KOH) electrolyte, enabling its direct reuse in new aluminium-air batteries and supporting sustainability.

[0061] The present disclosure provides a method for operating in a closed-loop system that recycles residues from the purification step back into battery production, thereby minimizing waste and reducing environmental impact.

[0062] The present disclosure provides a method that is scalable for industrial applications, making it feasible to implement on a larger scale within the aluminium-air battery recycling industry.

[0063] The present disclosure provides a method that ensures improved material efficiency, reducing the loss of valuable materials and promoting the efficient use of resources within the recycling process.

Claims

We Claim:

1. A method for recycling aluminium-air batteries, comprising the steps of: precipitating, at a precipitation unit (108), from a solution recovered from a feedstock from the Aluminium-Air batteries, aluminium trihydroxide in fine white powder form; wherein the solution remaining after precipitation is a potassium salt solution; and performing electrodialysis, in an electrodialysis unit (114), on the potassium salt solution to convert the potassium salt solution to KOH electrolyte and an acid, wherein the electrodialysis is carried out using ion-selective membranes.

2. The method as claimed in claim 1, comprising the step of: using the acid obtained from the electrodialysis unit (114) in the precipitation unit (108).

3. The method as claimed in claim 1, comprising the step of: filtering, using a filtration unit (104), the feedstock from the aluminium-air batteries to remove suspended particles of aluminium trihydroxide and impurities to recover the solution.

4. The method as claimed in claim 3, comprising the step of: washing and drying, using a first washing and drying unit (106), the removed suspended particles of aluminium trihydroxide and impurities to remove soluble impurities and collect the aluminium trihydroxide in a dry powder form.

5. The method as claimed in claim 2, comprising the step of: purifying, using a second washing and drying unit (112), the precipitated aluminium trihydroxide from the precipitation unit (108) to get aluminium trihydroxide in a high-purity powder form.

6. A system (100) for recycling aluminium-air batteries, the system comprising: a precipitation unit (108), for precipitating aluminium trihydroxide in fine white powder form a solution recovered from a feedstock from the Aluminium-Air batteries; wherein the solution remaining after precipitation is a potassium salt solution; and an electrodialysis unit (114) for performing electrolysis on the potassium salt solution to convert the potassium salt solution to KOH electrolyte and an acid, wherein the electrodialysis unit (114) comprises ion-selective membranes.

7. The system (100) as claimed in claim 6, wherein the system uses the acid obtained from the electrodialysis unit (114) in the precipitation unit (108).

8. The system (100) as claimed in claim 6, comprising a filtration unit (104) for filtering the feedstock from the aluminum-air batteries to filter out suspended particles of aluminium trihydroxide and impurities to recover the solution.

9. The system (100) as claimed in claim 8, comprising a first washing and drying unit (106) for washing and drying the filtered out suspended particles of aluminium trihydroxide and impurities to remove soluble impurities and collect the aluminium trihydroxide in a dry powder form.

10. The system (100) as claimed in claim 7, comprising a second washing and drying unit(112) to purify the precipitated aluminium trihydroxide from the precipitation unit (108) to get aluminium trihydroxide in a high-purity powder form.

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