A highly effective system for palladium dissolution under mild conditions

A highly effective system for palladium dissolution under mild conditions - page 9 In the present work, a new method has been introduced for the dissolution of palladium under very mild conditions. Palladium was quickly dissolved in some particular organic solvents including acetonitrile, ethyl acetate or acetic acid containing low concentrations of hydrochloric acid, hydrogen peroxide and CaCl2. Among these three organic solvents, acetic acid showed the highest rate of palladium dissolution. The rate of 1200 gm-2h-1 was measured at room temperature in acetic acid containing 0.5 M HCl, 0.2 M H2O2 and 0.2 M CaCl2 . The dissolution rate significantly increased to 4500 g m-2 h-1 by raising the temperature up to 60 oC. The dissolved palladium was precipitated out using Zn powder as a reducing agent. This new leaching method is highly promising to find industrial applications for recovery of palladium from both primary and secondary sources like,PGM ores, spent catalysts, copper anode slime and jewelry scraps.