Optimization of copper extraction from spent LTS catalyst (CuO–ZnO–Al2O3) using chelating agent: Box-behnken experimental design methodology

The objective of the present work is to investigate the extraction of copper from spent low temperature Shift catalyst using EDTA, as chelating agent and optimization of the parameters that influence the extraction of copper. Response surface methodology was applied for designing the experiment and to determine the optimal experimental conditions. Most influencing parameters such as concentration of EDTA, solid to liquid ratio and particle size of catalyst were optimized based on 3 factors 3 levels box behnken design which requires 15 run of experiments for designing a response surface. The high value of regression coefficient R2 (0.981) indicates a good correlation between predicted and experimental response, which confirms the acceptability of the proposed model.The optimum conditions were found as—concentration of EDTA: 0.5889 M, solid to liquid ratio: 0.02 and particle size: 90 μm. Under these optimum conditions, the experimental value of extraction of copper was estimated as 94.5% which seems very close to predicted response.