Quaternary ammonium compounds for froth flotation of silicates from an iron ore

摘要

The present invention relates to a froth flotation process in which silicates are separated from an iron ore in the presence of a collector containing a quaternary ammonium compound having the formula R₁R₁N⁺R₃R₄ 1/z X^z- (I), in which the groups R₁ independently are hydrocarbon groups, preferably aliphatic groups containing 6-14 carbon atoms and/or the group R₂-(OR₇)_m-OR₈-, where the groups R₂ independently are acyl groups containing 6-14 carbon atoms, the groups R₇ independently are alkylene groups containing 2-4 carbon atoms, the groups R₈ independently are alkylene groups containing 2-3 carbon atoms and m is a number from 0-5, R₃ and R₄ independently are alkyl groups containing 1-4 carbon atoms or groups (R₅O)_pH, where the groups R₅ independently are alkylene groups having 2-4 carbon atoms and p is a number from 1-4, X is an anionic group, and z is the charge of the anion X. This collector has a high selectivity to concentrate silicates in the froth product, while a high yield of iron minerals is maintained in the bottom concentrate or concentrates.