Preparation and kinetic modeling of β-Co(OH)2 nanoplates thermal decomposition obtained from spent Li-ion batteries

- Recovery of Co by hydrometallurgical route from spent lithium-ion batteries.
- Preparation of precursor by precipitation method.
- Production of Co3O4 nanoplates by thermal decomposition in air.
- Advanced isoconversional kinetic study of nano Co3O4 preparation.

An advanced solid-state kinetic analysis was used to investigate the thermal decomposition kinetic modeling of the cobalt hydroxide nanoplates synthesized from spent lithium-ion batteries (LIBs). The as-synthesized and calcined products were characterized by powder X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), thermal analysis (DSC-DTA-TGA), and scanning electronic microscopy (SEM). Kinetic analysis showed that complex decomposition of β-Co(OH)2 in air occurred through two consecutive reactions in the 120-260 °C temperature interval. The reaction mechanism of the whole process can be kinetically characterized by two successive reactions: a phase boundary contracting reaction followed by a Prout-Tompkins autocatalytic equation. Mechanistic information obtained by the kinetic study was found in good agreement with FT-IR and SEM results.

Field emission scanning electron microscope images of (a and c) precursor and (b and d) its calcination product at 300 °C for 3 h in air.136