Journal of Electroanalytical Chemistry, Vol.838, 23-32, 2019
Galvanic deposition of Pd2+ ion in chloride solution by using different three dimensional electrodes
The influence of different three-dimensional (3D) electrodes in recovering palladium from chloride ion solution by using a galvanic batch cell is presented in this study. Palladium is reduced at the cathode and zinc is oxidized at the anode. The performances of 3D electrodes used as cathodes in this study, namely reticulated vitreous carbon (RVC) and porous graphite (PG) were assessed based on the percentage of palladium removal. The results show that RVC produced a better performance than PG in recovering palladium from the chloride solution with Pd2+ concentration decreased from initial values to less than 0.1 mg L-1 after 2 h, in the order of RVC > PG. Cyclic voltammograms show that RVC and PG undergo redox reaction within the range 1500 mV to - 200 mV. It was also found that RVC treated with H2SO4 has a higher conductivity than PG, thus it improves the electrocatalytic activity of the cathode. Surface morphology analysis confirms that Pd is deposited on both RVC and PG.
Keywords:Galvanic deposition;Palladium recovery;Three dimensional electrode;Reticulated vitreous carbon;Porous graphite