Conceptual mechanism and kinetic studies of chelating agent assisted metal extraction process from spent catalyst

Metal extraction from spent catalysts using chelation technology is an acknowledged concept, however an underlying mechanism and kinetics associated with the process is still inexplicable. Therefore, efforts have been made to propose a generalized framework for extraction process and rate determining step was identified. Various empirical models were analyzed to choose the optimum one regarding their relative accuracy of fitting experimental data. Peleg model was considered the best fitted model with lowest root mean square error (±2.33%) and highest linear regression coefficient (0.9937). Thermodynamic analysis suggests activation energy of 24.8 kJ/mol and 12.07 kJ/mol for cobalt and molybdenum, respectively.