Abstract: The slag of kaolin in Guangxi after scrubbing, grinding, classification, high intensity magnetic separation, can produce the quartz sand with SiO₂ 99.82%, but the content of Fe₂O₃ is high to 113 μg/g, and the iron hosts in the mica and tourmaline.The flotation test was carried out to remove iron in the mica and tourmaline, to make the Fe₂O₃ content in quartz sand decrease to 80 μg/g and meet the requirements of the photovoltaic industrial.The results show that: first, mica reverse flotation was carried out in the acidic condition of pH=2.5 by using mixed amine and kerosene, and then tourmaline reverse flotation was carried out under the subalkaline condition of pH=7.8 by using sodium oleate, the final proceeds of the Fe₂O₃ content of the quartz sand can be reduced to 74 μg/g, the purity of SiO₂ can be increased to 99.89%, and the recovery rate of SiO₂ is 94.61%.

Key words: Quartz sand produced by the slag of kaolin, Iron removal, Mica reverse flotation, Tourmaline reverse flotation