Abstract: Flotation capabilities of bis (2-hydroxylethyl) dodecylamine to hematite and quartz were investigated in laboratory via single mineral flotation and manual mixed mineral separation.Single mineral flotation test results indicate that bis (2-hydroxylethyl) dodecylamine has better collectability to quartz，with natural slurry pH，collector concentration is above 13.33 mg/L，the recovery of quartz is more than 90%，while the hematite has relatively lower recovery，thus weak floatability to hematite，and the maximum flotation recovery of hematite is no more than 70%.Separation results of manual mixed mineral indicate that bis (2-hydroxylethyl) dodecylamine can separate hematite and quartz mixtures with the existence of starch.And the optimized separation results with 86.86% iron recovery and 65.28% iron grade in concentrate is achieved with natural slurry pH，bis (2-hydroxylethyl) dodecylamine concentration is 20 mg/L，starch concentration is 3.33 mg/L.Zeta potential experimant results indicate that collecting performance of bis (2-hydroxylethyl) dodecylamine to quartz is achieved mainly because electrostatic adsorption between collector and quartz surface.

Key words: Bis (2-hydroxylethyl) dodecylamine, Hematite, Quartz, Cationic reverse flotation