Dissolution kinetics of vanadium from black shale by activated sulfuric acid leaching in atmosphere pressure

• It's an environment-friendly method to extract vanadium from black shale.
• Dissolution kinetics of vanadium is studied in this paper which is absent in the former studies.
• Low grade black shale of 0.61% (V2O5 mass fraction) can be processed by this method.

The kinetics of vanadium dissolution from black shale by activated sulfuric acid leaching is presented. The effects of black shale particle size, sulfuric acid concentration, dosage of CaF2, and reaction temperature on vanadium extraction rate were determined. The results obtained show that an extraction of about 80% is achieved using less than 45 μm (− 45 μm) black shale particle size at a reaction temperature of 90 °C for 120 min reaction time with 100 g/L sulfuric acid concentration and in the presence of 60 kg/t ore of CaF2. The solid/liquid ratio was maintained at 1:30 g/mL. The apparent activation energy was determined as 90.19 kJ/mol at 70–90 °C and 201.96 kJ/mol at 50–70 °C. The reaction orders with respect to sulfuric acid concentration and catalyst CaF2 were 0.50 and 1.56, respectively.