Abstract: Through the flotation tests of single mineral, the flotation performance of quartz and magnetite were investigated with Gemini collector Gemini-31503 and the lauryl amine as collector respectively. The results showed that Gemini collector 31503 had better collecting ability to quartz in a wide pH range and good selectivity in quartz, and its performance was much superior to the lauryl amine. With the Gemini-31503 used as collector, the reverse flotation tests on the artificial mixed ores of quartz and magnetite were made, obtaining good separation index without any other reagents added. The Zeta potential measurements and infrared spectroscopy results showed that Gemini-31503 adsorption on the two minerals surface is mainly electrostatic adsorption. Under the same conditions, Gemini-31503 adsorption on quartz surfaces is higher than that on the magnetite. 

Key words: Gemini collector, Lauryl amine, Quartz, Magnetite, Adsorption capacity, Selectivity