Dissolution kinetics of chromite overburden by using mineral acids

Two different mineral acids were used to determine the kinetics of dissolution of Ni and Fe from chromite overburden. Various leaching parameters were studied such as acid concentration, pulp density, temperature and particle size. Both Fe and Ni dissolution followed 1st order irreversible kinetics. The activation energy was also measured. Unified rate equations were established for Ni and Fe dissolution for two different mineral acids, HCl and H₂SO₄. The dissolution reaction was observed to follow diffusion control-dense-constant size spherical particles.