Recovery of copper from simulated ammoniacal spent etchant using
sterically hindered beta-diketone
sterically hindered beta-diketone
(School of Chemistry and Chemical Engineering, Central South University, Changsha 410083, China)
Abstract: The solvent extraction of copper from simulated ammoniacal spent etchant with 1-(4'-dodecyl)-phenyl-3-tertiary butyl- 1, 3-octadione (HR) was studied, and a model of extraction isotherm was proposed and verified with equilibrium extraction constant. The influence of equilibration time, extractant concentration and phase ratio on the extraction of copper was studied at (298±0.5) K. For the spent etching solutions containing 112.98 g/L Cu, 6 mol/L NH3 and 1 mol/L NH4+, the optimal solvent extraction condition of copper was obtained in one-stage solvent extraction at phase ratio of 5:4 with 40% HR in sulphonated kerosene for 5 min. The copper concentration in the raffinate decreased to 63.24 g/L and raffinate can be favorably recycled to the etching solution. The stripping studies were carried out with the simulated copper spent electrolyte containing 30 g/L Cu and 180 g/L H2SO4. The stripping ratio is 98.27% from the loaded organic phase after one-stage stripping at phase ratio of 1:2 at (298±0.5) K.
Key words: spent ammoniacal etchant; copper recovery; solvent extraction; beta-diketone