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Recent increases in the demand for automotive lithium-ion batteries (LIBs) have led to higher needs for critical materials like lithium, cobalt, nickel, and graphite. Consequently, recovering materials from spent batteries has gained importance. This study aimed to (1) develop a mechanical pretreatment method for separating and concentrating materials from spent NCM811 cells and (2) evaluate the economic, environmental, and shortage potentials of these fractions. The pretreatment involved grinding and granulometric separation, producing six particle-size fractions. The main novelty of the study was the assessment to identify the particle size fractions which are priorities for recycling for decision-making by recycling companies, optimizing their resources and efforts. Analysis showed that the finest fraction (n < 0.5 mm) had 85% of lithium, 77.4% of cobalt, 75.1% of manganese, and 68.5% of nickel. This fraction represented 40.4% of the processed mass and had the highest economic value (USD 3669/ton NCM cell). This fraction was also prioritized for recycling due to its superior environmental impact (103,788 kg CO2-eq/ton NCM cell) and scarcity considerations. Furthermore, the black mass of NCM was the priority for recycling and had greater economic, environmental, and supply risk potential than the black mass of LFP cells. [ABSTRACT FROM AUTHOR]

Lithium-ion batteries are widely used as a power source for portable devices and electrical vehicles (EVs). After their useful life, they can provide a secondary source from which to obtain some materials which make them up, such as lithium and cobalt. However, the metallurgical route which will be used to recover them must be considered. Therefore, is crucial that many efforts to develop more environmentally favorable recovery processes be pursued. Due to this, the present work aimed to use 1.5 M DL-malic acid and compare it to 2 M sulfuric acid, employing heat pretreatment of 1 h and 3 h to remove the powder cathode binder polyvinylidene fluoride (PVDF); for all conditions, experiments were carried out with and without adding the oxidizing agent hydrogen peroxide. The PVDF temperature degradation occurred at 630 °C. The best yields occurred in the presence of H2O2 10% v/v and heat pretreatment. With sulfuric acid (1 h) it was possible to recover 33.49% Co and 4.63% Li, and (3 h) 36.36% Co and 4.64% Li. With DL-malic acid it was possible to recover (1 h) 29.78% Co and 3.44% Li, and (3 h) 32.73% Co and 3.99% Li. [ABSTRACT FROM AUTHOR]

Currently, the recovery of materials from secondary sources is increasingly necessary because of the scarcity of materials. Significant amounts of rare earth elements (REE) are found in permanent neodymium-iron-boron (NdFeB) magnets, used in various electrical and electronic equipments, such as mobile phones. However, the estimated recycling rate for REEs is only 1%. Hydrometallurgical routes are the most commonly used for REE recovery from secondary sources. This route usually uses inorganic acids, which are expensive and toxic. Thus, in this work the leaching efficiency of organic acids (acetic and citric) in leaching the REE (neodymium and praseodymium) present in magnets of obsolete or defective mobile phones was evaluated. Different concentrations of acids, solid/liquid relations, times and leaching techniques (microwave, ultrasound and conventional) are also evaluated. The results indicate that acetic and citric acids have the potential to leach Nd and Pr. Microwave leaching was the most effective method, compared to ultrasound and conventional methods. In microwaves, citric acid at 0.5 M (ratio s/l 1/100) leached 57% of Nd and 58% of Pr. Acetic acid at 0.5 M (s/l ratio—1/100) leached 48% of Nd and 65% of Pr, in 15 min. Furthermore, both citric acid and acetic acid also leached high percentages of iron (51% and 72%, respectively). [ABSTRACT FROM AUTHOR]

Besides neodymium, the chemical composition of Neodymium–Iron–Boron (NdFeB) permanent magnets possibly contains other rare earth elements (REEs) such as praseodymium, dysprosium, and terbium. Among its applications, NdFeB magnets are essential for Hard Disk Drives (HDDs) in computers for data storage, in Mobile Phones (MPs), and in acoustic transducers. Because REEs were classified as critical raw materials by the European Union and the USA, the recycling of them has become an important strategy to diminish supply risk. Therefore, in this publication, the authors have uncovered the recycling potential estimate (RPE) of these four REEs from both end-of-life (EoL) secondary sources. The results were based on the time-step method, using in-use stock and sales data from Brazil over the last decade (2010–2019). Moreover, the NdFeB magnets were characterized by content and weight to a more accurate RPE. The EoL generation over the decade studied showed different scenarios for MPs and HDDs, mainly due to lifespan, social behavior regarding storage and usage, and resources. Under those circumstances, the RPE revealed 211.30 t of REEs that could return as raw materials in the last decade, of which approximately 80% is neodymium. Unfortunately, recycling rates are still too low, even more so in Brazil, which is problematic for the future REE supply chain and electronic waste figures. [ABSTRACT FROM AUTHOR]