LEACHING STUDIES FOR THE RECOVERY OF METALS FROM THE WASTE PRINTED CIRCUIT BOARDS (PCBs)

摘要

Leaching studies were carried out for the recovery/recycling of metals from PCBs containing 17.05% Cu, 0.74% Ni, 1.74% Fe, 4.35% Pb and 8.32% Sn using various acids such as H_2SO_4, HCl and HNO_3. While sulfuric acid was not a suitable leachant for the dissolution of metals from PCBs, hydrochloric acid selectively dissolved tin. The nitric acid was found to be effective lixiviant with the recovery of 99.99% Cu, Fe, Ni and 36.7% Pb in 6M HNO_3 at S/L ratio of 100 g/L and 90°C. The kinetic studies carried out with 2M and 4M HNO_3 at 90°C showed "Ash diffusion control dense constant size-spherical particles" model.