Selective Electrochemical Recovery of Co, Ni, Mn from NMC Leachates using NADES-Dataset,2026

Abstract / Summary: This dataset supports the study on electrochemical recovery of Co, Ni, and Mn from NMC 622 cathode leachates using natural deep eutectic solvents (NADES). The data includes raw and processed results from cyclic voltammetry (CV), chronopotentiometry (CP), UV–Vis spectroscopy, ICP-OES metal quantification, electrochemical impedance spectroscopy (EIS), and associated modeling outputs. Research Hypothesis: Transition metals in NMC leachates complexed with NADES are electrochemically addressable and can be selectively reduced under current-programmed galvanostatic conditions. By controlling applied current and catholyte volume, the reduction efficiency and Faradaic utilization of Co, Ni, and Mn can be maximized independently, providing a path to energy-efficient, selective metal recovery. Description of Data and Collection: Electrochemical Data: CV scans (10–100 mV s⁻¹) and CP voltage responses (50–100 mA) for varying catholyte volumes (15–30 mL) were recorded using a DHElecChem7000 workstation in divided H-cells. Metal Speciation: UV–Vis spectroscopy and ICP-OES quantified M²⁺/M³⁺ concentrations before and after electrochemical reduction. Faradaic efficiency calculations and residual metal concentrations were derived. EIS Data: Nyquist and Bode plots across 1 mHz–100 kHz, with plateau-resolved Rs, Rct, and Warburg parameters, describe interfacial and diffusion limitations. Model Outputs: Three-layer modeling data capturing volumetric charge density, metal-specific reduction kinetics, and Faradaic efficiency constraints, along with quadratic response-surface optimization results. Notable Findings: Co(III) reduction is optimized at 20 mL catholyte and 60 mA with 93.88% conversion; residual Co(III) = 77.37 mg L⁻¹. Ni(III) and Mn(III) conversions peak at 20 mL, 100 mA with 75.68% and 91.35%, respectively. Faradaic efficiency is maximized at intermediate currents, balancing electron utilization and metal recovery. EIS analysis indicates reduced Rct at higher currents, confirming enhanced electron transfer and interface activation. Multi-layer modeling demonstrates the critical interplay between current, catholyte volume, and metal-specific kinetics, enabling process design optimization. Interpretation and Use: Data can be used to validate NADES-based selective metal recovery, develop electrochemical process maps, and optimize multi-metal reduction strategies. Researchers can interpret CV and CP data to identify redox windows, use UV–Vis/ICP-OES data to quantify metal conversion, and EIS data to understand interfacial kinetics. Modeling outputs enable prediction of operating conditions for maximum conversion and energy efficiency. Data Format: CSV files for raw and processed electrochemical, spectroscopic, and modeling data. Recommendations for Reuse: Researchers may reproduce experiments for similar NMC-NADES systems or use datasets for modeling and optimization of selective electrochemical recovery processe