Abstract: Al is one of the important impurities to be removed in quartz sand. Al impurities are difficult to be completely removed due to their strong bonding strength with the matrix, high content, and likelihood to exist inside the particles. In this study, starting from the impurity removal mechanism, a quartz ore sample from Fengyang, Anhui was treated by a method of high temperature calcination, quenching and acid leaching of quartz sand to improve the removal efficiency of the impurities. The experimental results showed that the content of the Al impurities could be reduced to 45.89 g/t from 1148 g/t after calcining and quenching quartz sand at a high temperature of 900℃, and then heating and acid leaching with a highly corrosive HNO₃-HCl-HF ternary mixed acid and the removal ratio reached 96.0%. The total impurity content could be reduced to 256.1 g/t from 2059.9 g/t, and the removal ratio reached 87.6%. The observation of the microstructure and morphology of the quartz sand before and after calcination, quenching and acid leaching showed that a large number of irregular connected cracks and surface corrosion pits appear in the treated quartz sand, which is conducive to the infiltration of the acid into the particles and improves the impurity removal effect. The general multiphase shrinking core model was used to analyze the experimental results, and it was found that the rate-controlling step of the acid leaching was the internal diffusion of the reaction products. The activation energy of the reaction was reduced by 69% after the calcination, which indicated that the direct calcination and quenching of the quartz sand particles was beneficial to the acid leaching and impurity removal treatment of the quartz sand.