Selective flotation of a complex iron ore using mixed cationic collectors with reduced starch dosage

Flotation is a critical technique for upgrading complex iron ores containing iron-bearing silicates, yet selective separation remains challenging due to similar surface properties of minerals. This study investigates mixed cationic collectors by combining amidoamine either with etherdiamine or quaternary ammonium salt alongside reduced starch dosages to enhance flotation selectivity. Microflotation tests on hematite, quartz, and aegirine, both individually and in mixed systems supported by zeta potential and contact angle analyses, reveal that mixed collector systems synergistically enhance the floatability of iron-bearing silicates while maintaining strong hematite depression. Binary and ternary artificial ore simulation tests confirm effective separation of hematite (recovery > 85%) from silicate gangue under optimized reagent conditions. Controlled silicate rejection was achieved using minimal starch dosages particularly for medium-sized particles. Overall, these findings demonstrate that tailored mixed collector systems can optimize reagent efficiency offering a promising approach for beneficiation of low-grade complex iron ores, contributing to more sustainable and cost-effective mineral processing operations.