THE LEACHING BEHAVIOUR OF HNO_3 SOLUTION IN ISHIAGU ORE, EBONYI STATE NIGERIA

Abstract

The leaching behavior of HNO_3 solution was studied. The sourced sample was pulverized and the chemical characteristic determined. The results of the chemical analysis of the ore based on AAS revealed that the ore contained 31.75% Pb, 0.93% Zn, 0.525% Cu, 0.165%Mn, 0.0702% Mg, 0.0202% Ca, 9.23% Fe and 0.0056% Ni. The mineralogical analysis by X-ray diffraction technique revealed that the ore contained galena and other associated minerals. The results showed that the leaching of lead from galena concentrates increases with HNO_3 concentration, temperature, stirring speed, solid liquid ratio and a decrease in particle size increased the leaching rate positively. The study, also showed that complete dissolution of lead was achieved at 70oC, while other parameters were fixed. It was found that mixed kinetic is the controlling mechanism for this study. The E_a was determined to be 37.57kJ/mol. The reaction order and Arrhenius constant were calculated to be 0.179 and 〖79 X S〗^(-1),respectively.