Green and efficient recycling method for spent Ni-Co-Mn lithium batteries utilizing multifunctional deep eutectic solvents.

Given the growing volume of discarded lithium-ion batteries (LIBs), the extraction and recovery of valuable metals through environmentally-friendly solvent processes have become crucial, but they remain challenging tasks. Deep eutectic solvent (DES), an innovative and green solvents, have demonstrated significant promise in the extraction of valued metal elements from spent LIBs. This work employed a multifunctional DES based on natural molecules dimethyl-beta-propiothetin (DMPT) and ethylene glycol (EG) for the efficient leaching of transition metal ions. Under the reduction effect of EG and the action of carboxyl groups and chloride ions in DMPT, the leaching rate of Li, Ni, Co, and Mn can reach 99.59%, 99.28%, 99.04%, and 99.45%, respectively. Furthermore, DFT calculations were employed to explore the microstructure of DES and its interactions with metal ions. The main active site in the DES molecule is near the chloride ion, and DES binds most strongly to Mn, followed by Co, and weakest to Ni. This work avoids the use of volatile acids and demonstrates great potential in extracting valuable metals, providing a sustainable and environment-friendly alternative for the efficient recycling of waste LIBs.

Recycling of waste lithium-ion batteries via a one-step process using a novel deep eutectic solvent.

Deep eutectic solvents (DESs) possess excellent solubility and selectivity, making them suitable for extracting valuable metals and serving as a green alternative in the recycling process. This work introduces a low-viscosity DES consisting of dimethylthetin, oxalic acid, and water for the comprehensive recovery of cathode materials from LIBs. Leaching parameters such as ratio (1:1), leaching temperature (60 °C), and reaction time (15 min) for were systematically optimized, resulting in a selective separation efficiency of 99.98 % for lithium ions. Furthermore, in-situ regeneration of the precursor can be achieved during the leaching process. Charge-discharge tests indicate that the initial charge and discharge capacities of the regenerated battery are 166.8 mAh/g and 138.4 mAh/g, respectively. The DES demonstrates stability and can be easily recycled by replenishing the consumed components. This proposed strategy facilitates the reintroduction of nonrenewable resources into the supply chain and reduces the environmental impact of heavy metals, aligning with the principles of a circular economy.

Extraction of precious metals from used lithium-ion batteries by a natural deep eutectic solvent with synergistic effects.

As the demand for lithium-ion batteries rises, the growing quantity of waste produced from lithium-ion battery electrode materials becomes an issue of concern. We propose a novel approach for effectively extracting precious metals from cathode materials that address the problem of secondary pollution and high energy consumption that arise from the conventional wet recovery process. The method employs a natural deep eutectic solvent (NDES) composed of betaine hydrochloride (BeCl) and citric acid (CA). The leaching rates of manganese (Mn), nickel (Ni), lithium (Li), and cobalt (Co) in cathode materials may reach 99.2 %, 99.1 %, 99.8 %, and 98.8 %, respectively, due to the synergy of strong coordination ability (Cl-) and reduction (CA) in NDES. This work avoids the use of hazardous chemicals while achieving total leaching in a short period (30 min) at a low temperature (80 °C), achieving an efficient and energy-saving aim. It reveals that NDES has a high potential for recovering precious metals from cathode materials and offers a viable, environmentally friendly method of recycling used lithium-ion batteries (LIBs).

High-efficiency recycling of spent lithium-ion batteries: A double closed-loop process.

Due to the scarcity of raw materials and negative environmental effects, it is essential to selectively recover lithium and other transition metals from end-of-life lithium-ion batteries (LIBs). Here, we propose a dual closed-loop process for resource utilization of spent LIBs. As an alternative to strong inorganic acids, deep eutectic solvents (DESs) as green solvents are employed for the recycling of spent LIBs. The DES based on oxalic acid (OA) and choline chloride (ChCl) achieves efficient leaching of valued metals within a short time. Through the coordination adjustment of water, it can form high-value battery precursors directly in DES, changing wastes into valuables. Meanwhile, water as a diluent can achieve the selective separation of lithium ions via filtration. More importantly, DES can be perfectly re-generated and recycled many times, indicating that the process is cost-effective and eco-friendly. As experimental proof, the re-generated precursors were used to produce new Li(Ni0.5Co0.2Mn0.3)O2 (NCM523) button batteries. The constant current charge-discharge test revealed that the initial charge and discharge values of the re-generated cells were 177.1 and 149.5 mAh/g, respectively, corresponding to the performance of commercial NCM523 cells. The whole recycling process is clean, efficient, and environment-friendly, realizing the double closed loop of spent battery regeneration and deep eutectic solvent re-use. This fruitful research demonstrates DES has excellent potential for recycling spent LIBs and provides an efficient and eco-friendly double closed-loop solution for the sustainable re-generation of spent LIBs.

[Protective effects of azithromycin on adriamycin-induced nephropathy with albumin overload in mice].

OBJECTIVE: To study the protective effects of azithromycin on renal damage induced by doxorubicin and albumin in mice. METHODS: Forty male BALB/c mice were randomly divided into blank control group (Ctrl group), renal damage model group (ADR+BSA group), azithromycin treated group (Azm group) and prednisone acetate positive control group (Pdn group) in accordance with random number table method. Mice in ADR+BSA, AZM and Pdn group were injected intravenously with 9.8 kg-1 doxorubicin five days a week, 10 kg-1 serum albumin was injected intraperitoneally, and normal saline was administered to the control group for 4 weeks to establish renal damage model. After that, AZM group was given daily. 62.5 kg-1 azithromycin was intragastrically administered. The Pdn group was given 12.5 kg-1 prednisone acetate daily, the other two groups were given the same amount of normal saline. After 6 weeks, the urine volume was collected and recorded for 24 hours to detected urine protein amount and endogenous creatinine clearance rate (Ccr). Serum biochemical indicators and serum immune factors were detected. RESULTS: Compared with the Ctrl group, the 24 h urine protein level of the ADR+BSA group was increased significantly (P＜0.05), and the Ccr was decreased significantly (P＜0.05). After the azithromycin treatment, the 24 h urine protein was decreased significantly (P＜0.05), while the Ccr was increased significantly (P＜0.05) compared with ADR+BSA group. CONCLUSION: Azithromycin has a protective effects on the renal damage induced by doxorubicin and albumin in mice.