Dissolution kinetics of iron from diasporic bauxite in hydrochloric acid solution

Abstract

The dissolution of iron in the bauxite ore including diasporite mineral from Kayaderesi region in Mugla-Milas city, Turkey was investigated in hydrochloric acid solution. The bauxite was calcined at different temperatures and periods, and then dissolved in hydrochloric acid solution. After determining the optimum calcination conditions as 1-hour period at 1173 K temperature and the optimum acid concentration as 8 M HCl, dissolution temperature and period for removal of iron from the bauxite were examined experimentally. In calculations of dissolution kinetics of iron, the experimental data showed that the dissolution process was controlled by interfacial chemical reaction with the apparent activation energy of 41.38 kJ/mol. First order reaction kinetics in shrinking core model was found to fit the experimental results. The dissolution of iron from the bauxite was achieved as 96.46% together with 23.40% aluminium.