The Open Mineral Processing Journal

2009, 2 : 31-36
Published online 2009 July 16. DOI: 10.2174/1874841400902010031
Publisher ID: TOMPJ-2-31

Hydrometallurgical Recovery of Nano-Palladium from Spent Catalyst

M. A. Barakat , G. A. EL-Mahdy , M. Hegazy and F. Zahran
Central Metallurgical R & D Institute, P.O. Box 87, Helwan 11421, Cairo, Egypt;

ABSTRACT

Hydrometallurgical recovery of nano-palladium (Pd) from spent Pd/Al2O3 catalyst has been investigated. The Pd content in the spent catalyst sample was assayed to be 0.42% while the remainder was mainly aluminum oxide. Mixture of HCl and AlCl3 was studied as leaching agent for the sample. The Pd was deposited with formic acid. Different parameters affecting leaching and deposition processes such as, time, temperature, liquid/solid ratio, were investigated. Phase of spent catalyst were identified by X-ray diffraction (XRD) analysis. The deposited Pd was characterized by scanning electron microscope (SEM), transmission electron microscope (TEM) and energy dispersive X-ray (EDX) for identification of the grain size and composition. The deposited palladium was found to be in the nano-size range (34.5-70.5 nm).

Keywords:

Spent catalyst, palladium, leaching, recovery, electroless deposition.