Abstract: Flotation behavior of three typical bauxite resources in China was investigated using BK430 as collector. Monomineral experiment results showed that: BK430 have more intensively collecting ability for kaolinite and illite than diaspore with no depressor and weak acid conditions; the collecting ability was enlarged further when added with depressor DF for diaspore; artificial mixed minerals and monomineral test results fit well. Reverse flotation tests for desilication have been carried out on a bauxite, Henan, with alumina silica ratio of 4.43. After desliming—reverse flotation process, concentrate with Al₂O₃/SiO₂ of 9.21, Al₂O₃ recovery of 62.49% was received. BK430 is expected to become a reverse flotation collector for desilication of bauxite under nearly neutral condition.

Key words: Bauxite, Reverse flotation, BK430, Nearly neutral