Abstract
A series of experiments were conducted to examine the effect of citric acid on the dissolution of zerovalent zinc. The effects of citric acid concentration, the presence of anions and temperature were studied. The results have shown that zinc dissolution registered a maximum of 34% with 0.5M citric acid after 270 min and that the nature of anions present with citric acid affected differently the dissolution rate. In fact, the presence of 2M nitrates with 0.5M citric acid dissolved totally zinc after 30min while 91.85% and 13.15% were dissolved in the presence of 2M chlorides and sulfates respectively after 270min. SEM analyses have shown that the morphology of the corroded surface depended on the composition of the solution. The kinetic study has shown that zinc dissolution was controlled by the chemical reaction in all cases and that the activation energy was 39.3 kJ mol-1.
