Recovery of manganese from sulfuric acid leaching liquor of spent lithium-ion batteries and synthesis of lithium ion-sieve

Recovery of Lithium and Manganese from Scrap LiMn2O4 by Slurry Electrolysis

“…Previous studies also indicated that LiMn 2 O 4 can be leached in acid solutions − and usually assisted by H 2 O 2 or NaHSO 3 . The effect of H 2 SO 4 concentration on the leaching efficiency of Mn and the electrode current efficiency are shown in Figure .…”

“…The leaching efficiency of Mn decreases from 96 to 54%, and Li is decreased slightly in the pulp density range of 25–125 g/L. This is because the content of H + in the electrolyte is not enough for leaching the excessive Mn via reactions –, and the leaching of LiMn 2 O 4 is an ion-exchange reaction between H + and Li via reaction , which conducted more easily than reactions – …”

“…This is because the content of H + in the electrolyte is not enough for leaching the excessive Mn via reactions V−VII, and the leaching of LiMn 2 O 4 is an ion-exchange reaction between H + and Li via reaction IX, which conducted more easily than reactions V−VII. 35 A high solid−liquid ratio contributes to high conductivity in the electrolyte. 22 As shown in Figure 7b, the anodic current efficiency increases with the rise of pulp density during the whole process and reaching to 65% at the pulp density of 125 g/L.…”

Sustainable and Convenient Recovery of Valuable Metals from Spent Li-Ion Batteries by a One-Pot Extraction Process

“…The pyrometallurgy process is simple and convenient for industrial applications, but the process involved has high requirements for equipment, has high energy consumption, and is not environmental-friendly. Hydrometallurgy has become the primary recovery method for spent LIBs due to the high extraction efficiency, low energy consumption, and low investment cost. − Acid and alkali are the classic extraction agents in hydrometallurgy to recover metals from spent LIBs, particularly inorganic acids, such as hydrochloric acid, , nitric acid, , and sulfuric acid. − Hydrogen peroxide is often used as a reducing agent to improve the extraction efficiency during the traditional inorganic acid extraction process . Moreover, high-quality equipment is needed to overcome the acid etching of inorganic acids.…”

Alkaline Leaching of Metals from Cathodic Materials of Spent Lithium-Ion Batteries

“…These include sulfuric acid [13,14], hydrochloric acid [15,16], orhophosphoric acid [17]. Hydrogen peroxide [13], glucose [10], sodium metabisulfite [18], ascorbic acid and tartaric acid [19] were used as reducers of M Organophosphorus acids such as bis (2ethylhexyl) phosphonic acid (D2EHPA) [20], bis (2,4,4,4-trimethylpentyl) phosphinic acid (Cyanex 272) [21,22] and 2-ethylhexyl phosphonic acid (PC88A) [23] have also been extensively studied as metal extracts. In addition, studies of combinations of different extractants were conducted to investigate the selective separation of metals in leachate liquor [21,23,24].…”