Preparation of Industrial Sodium Chromate Compound from an Indigenous Chromite Ore by Oxidative Decomposition

Pure chromate is an important raw material used extensively in chemical and metallurgical operations. Considering these uses, the oxidizing roasting process of an indigenous chromite ore to prepare industrial sodium chromate was investigated in this study. The effects of sodium carbonate to chromite mole ratio, reaction temperature, contact time and its thermodynamics-cum-kinetics behaviour were also discussed. The results showed that the reaction mechanism was greatly influenced as the temperature varies. A two-stage recovery process was found favorable for the conversion method and chromate conversion rate of 97.06% with minimal residual pollutants was achieved at optimal conditions. The residual products containing iron as characterized could be easily recovered to produce sponge iron, leading to complete detoxification and zero emission of chromium residue for defined industrial applications.