Phosphate ore processing depends on the origin of phosphate rock, which have widely differing characteristics, as a consequence depends on the nature of impurities to be removed. Flotation is the most used method for beneficiating phosphate rock. Bunge is one of the greatest industries in Brazil that produces fertilisers. Nowadays, they are in trouble with the high concentration of gangue minerals (siliceous) from which apatite is recovered. The goal of this research is to define a process to separate the siliceous gangue from Bunge phosphate ore for further apatite recovery using a column flotation. Bench-scale experiments for the reverse cationic flotation of siliceous gangue from this mineral using a cationic amine as collector were carried out at pH 9.5. The main variables were investigated experimentally based on a factorial design. According to the experimental results, it was possible to obtain a product with the demand concentration for further apatite recovery. Siliceous concentration on non floated fraction was under 8% and phosphate loss on concentrate was under 10%.