Intensification of potassium leaching from phosphorus-potassium associated ore with lauryl alcohol

In the present work, experiments have been performed for leaching potassium from phosphorus-potassium associated ore in hydrochloric acid/fluorite system. Surfactant or phosphoric acid extractant was added into the leaching system to enhance the leaching efficiency. The results show that alcohol chain length has great influence on potassium leaching and among the additives investigated, lauryl alcohol exhibits the largest promoting effect on potassium leaching and the leaching fraction of potassium can be increased from 89.5% to 97.8% with the addition of 1 mL of lauryl alcohol into 80 mL of leaching solution. The enhanced leaching observed in the presence of lauryl alcohol can be attributed to the hydrophobicity mechanism. The kinetic analysis shows that there are two distinct stages in the leaching process and the kinetics of both stages follows the classical shrinking core model with chemical reaction being the rate-controlling step.