Abstract
Low-rank coals (LRC) are abundant but underutilized due to
their hydrophilic nature and high oxygen content, which hinder flotation
efficiency. Traditional single-collector systems often result in low recovery
rates and high reagent consumption. This study investigates the use of a
mixed collector system comprising oleic acid (OA) and dodecane (D) to
improve LRC flotation. Response Surface Methodology (RSM) was
employed to optimize the dosing ratio of OA to D. Laboratory-scale flotation
tests demonstrated that mixed collectors significantly enhance flotation
efficiency, achieving recovery rates up to 65.5% and reducing ash values
from 55.6% to 16.7%. Optimal conditions were identified at a dodecane
dosage of 300 g/t and an oleic acid dosage of 255.5 g/t. The findings
underscore the potential of mixed collectors to enhance coal hydrophobicity,
thereby improving recovery and separation from gangue minerals. This
approach offers a sustainable solution for LRC beneficiation, minimizing
waste and enhancing economic viability.