Neutral-pH selective flotation of quartz using a biodegradable polymer collector: Toward HF-free sustainable beneficiation

ABSTRACT High-purity quartz is essential for advanced technological applications, yet its separation from feldspar remains challenging due to similar surface properties and the environmental impacts of conventional amine- and HF-based flotation reagents. This study presents the use of a biodegradable polymer collector (DR2200), which exhibit reduced environmental impact compared with conventional collector chemicals. Flotation behaviour and adsorption mechanisms were investigated using Hallimond tube and batch flotation tests combined with zeta potential, contact angle, FTIR, and atomic force microscopy analyses. Results show that DR2200 selectively adsorbs on quartz, altering surface charge and wettability, while feldspar surfaces exhibit limited interaction. AFM and FTIR analyses confirm the formation of a polymer adsorption layer on quartz through hydrogen bonding with surface silanol groups. Flotation experiments achieved quartz recoveries above 80% with minimal feldspar contents, demonstrating effective separation under environmentally benign conditions. The results highlight the potential of biodegradable polymer collectors as sustainable alternatives for industrial quartz beneficiation and contribute to cleaner mineral-processing technologies with reduced chemical hazards. Environmental advantages are discussed qualitatively, as a full life-cycle assessment comparing DR2200 with conventional collectors was beyond the scope of this study.