Low-temperature performance of cationic collector undecyl propyl ether amine for ilmenite flotation

- UPEA exhibits excellent low temperature (279 K) performance in ilmenite ore flotation.
- UPEA largely and selectively adsorbs onto the ilmenite surface.
- UPEA physisorbed onto the mineral surface.
- Adsorbance reduced with temperature raises was confirmed by thermodynamic analysis.

When conventional anionic collectors (e.g., fatty acids) are used in flotation separation of ilmenite and titanaugite, a high flotation temperature (>293 K) is generally required. However, it is crucial to develop low-temperature flotation processes for use in cold regions. This study demonstrates that the cationic collector undecyl propyl ether amine (UPEA) has outstanding collecting ability, selectivity, and low-temperature performance for ilmenite ore flotation. Various important factors that influence flotation performance, such as pH, UPEA dosage, and pulp temperature, were investigated by microflotation tests. Compared with a higher temperature (295 K), superior flotation recovery was obtained by closed-circuit flotation of actual ore at 279 K. Zeta potential measurements illustrated that large amounts of UPEA were selectively adsorbed on the ilmenite surface. Thermodynamic calculations and Fourier transform infrared analyses showed that adsorption of UPEA onto both mineral surfaces involved a physisorption process. Moreover, increasing the thermodynamic energy of UPEA molecules diminished interactions between UPEA and the minerals, resulting in decreased adsorption of UPEA with increasing temperature, as confirmed by adsorption analysis. The excellent low-temperature flotation performance of UPEA is consistent with the energy conservation policy of China, and the use of UPEA should be promoted in cold regions. This work provides new insights into the efficient separation of ilmenite from titanaugite at low temperatures.