| Abstract Scope |
Acid mine drainage (AMD) is one of the leading water pollutants in many countries with mining activities. AMD is caused by the oxidation of pyrite and other metal sulphides. When these metals get exposed to moisture and oxygen, leaching occurs, discharging sulphate and Iron. A mathematical model was developed to correlate the leaching rate constant to reaction variables: temperature, hydrogen peroxide concentration, solid to liquid ratio, and stirring speed using a Central Composite Design (CCD). The iron pyrite before and after leaching was characterized using Fourier Transform Infrared Spectra (FTIR) analysis, X-Ray diffraction (XRD) and scanning electron microscope (SEM) were used to characterize before and after leaching. It was found that the leaching rate decreases with an increased solid to liquid ratio, temperature, stirring speed, and acid concentration. The leaching kinetics followed the shrinking core model with the product layer diffusion model as the rate-limiting step. |