Effects of surfactants combination on iron ore flotation

•Frothing has not been played by specific frothers in cationic flotation of iron ore.•Frothers surpass etheramines in reducing bubble size and increasing foamability.•The partial replacement of the etheramines by frothers improved the selectivity.•The compatibility of molecular weight explains the improved selectivity.•The replacement of etherdiamine by 10% of ethermonoamine showed the best result.