Nadir toprak elementleri içeren hammaddelerin çözümlendirme ile değerlendirilme kinetiğinin incelenmesi

In this study, the leaching kinetics of Wigu Carbonite Complex ore contains rare earth elements in different acid solutions were investigated. In the experiments, two different acid solutions were used to prepare the solvent medium with the complex ore from Wigu Hill as a raw material. The leaching of ore in a solution may include multiple steps such as reaction and diffusion. The characteristics of the raw materials and reaction type are effective in determining the leaching mechanism. The shrinking core model was selected for the determination of leaching kinetics considering raw materials and reaction types. Although the shrinking core model contains five steps in itself, when these steps are formulated, only two steps are important for the determination of leaching kinetics. These two steps are classified as chemical reactions and diffusion through a product layer. Linear regression analysis, which is one of the least-squares regression methods, was performed to find the reaction rates. As a result of the linear regression analysis, determination coefficients were also calculated. The activation energy, which is another method used to determine the reaction mechanism, has been calculated. The Arrhenius equation was used to calculate the activation energy. The calculations of the activation energies were made for both two steps (chemical reaction and diffusion) by using hydrochloric and nitric acid solutions. The activation energies were calculated according to these two steps approaches. According to the results, the leaching mechanism of both cerium, lanthanum, neodymium, and praseodymium in the complex ores were mixed controlled under the selected conditions.