Quantitative Leaching of a Nigerian Iron Ore in Hydrochloric Acid

A study on the quantitative leaching of iron ore in hydrochloric acid solution has been undertaken. The elemental composition of the iron ore was also carried out using ICP-MS technique. The major elements in the iron ore include: Fe(66.7%); Al (0.2%); Si (5.2%); Ti (0.02%) and O (28.0%). Some traces of V, Ni, Zn, Ce, Cr, La, Y and Zr were also found. The effects of contact time, acid concentration, temperature, particle size and, the stirring speed on the dissolution of the iron ore have been investigated. The dissolution rate depends on the hydrogen ion concentration and temperature of the reaction system. The mechanism of dissolution appears to follow an exothermic pathway. The activation energy for the dissolution reaction was 13.63 kJmol^-1. About 92% of the total iron in the ore was dissolved within 120 min. by 12M HCl solution and 80°C using 0.1mm particle size. The optimum stirring speed was 30orpm.