Optimized Flotation of Zinc Oxide Ores: Synergistic Effects of Mixed Collectors and Desliming

Document Type : Original Research Paper

Author

Department of Mining Engineering, Sahand University of Technology, Tabriz, Iran

10.22111/jesm.2025.52007.1024

Abstract

The flotation of zinc oxide ores presents significant technical challenges due to their complex surface chemistry and fine particle size. This study investigates the flotation behavior of a zinc oxide ore (13–14% Zn, 3–4% Pb) from the Barmalek deposit using different collector systems—potassium amyl xanthate (KAX), cocoalkylamine acetate (Armac C), and a mixed collector system. Comprehensive mineralogical and liberation analyses confirmed the oxide-dominated nature of the ore and the presence of slime-generating fractions, which negatively affect flotation performance. Systematic flotation experiments were conducted using Taguchi design arrays (L8, L12, L18) to evaluate the effects of various parameters, including reagent dosages, pH, and flotation time, both with and without desliming. Results showed that KAX or Armac C alone provided limited recovery and selectivity. In contrast, the mixed collector system significantly enhanced zinc recovery and concentrate grade, particularly when combined with desliming. Under optimized conditions—pH 11, Na₂S 2800 ppm, starch 1000 ppm, sodium silicate 400 ppm, flotation time 4 minutes, xanthate 500 ppm (stage 1), xanthate 400 ppm (stage 2), and Armac C 300 ppm—zinc recovery reached 84.3% and concentrate grade exceeded 42%, while calcium recovery was minimized to 13.85%. Validation experiments confirmed the model predictions, although actual recoveries slightly decreased after accounting for slime losses. The findings demonstrate the synergistic potential of mixed collectors and highlight the critical role of desliming and reagent optimization in improving the flotation of refractory zinc oxide ores.

Keywords


Volume 1, Issue 4
December 2025
Pages 1-16
  • Receive Date: 02 October 2025
  • Revise Date: 27 November 2025
  • Accept Date: 22 December 2025
  • First Publish Date: 22 December 2025
  • Publish Date: 29 December 2025