Flotation Performance of Biodiesel as Collector for Beneficiation of Low- Grade Graphite Ore

Abstract

In pursuit of sustainable mineral processing, this study explores the use of biodiesel as a collector for the flotation of low-grade graphite ore. The flotation efficacy of a novel biodiesel collector for the selective recovery of graphite from low-grade ore with 89.5% ash content and 8.7% fixed carbon, using a Taguchi experimental design, was studied. Flotation performance was optimized by evaluating the influence of grind time, depressant sodium silicate dosage, and collector biodiesel dosage on weight recovery, ash content, and fixed carbon recovery. The optimal test configuration was observed at a grind time of 25 minutes, sodium silicate dosage of 1.67 kg/t, and biodiesel dosage of 2.32 kg/t. Under these conditions, the flotation process achieved a concentrate with 11.21% weight recovery, 2.74% ash content, and 94.42% fixed carbon. FTIR and GC analysis of the biodiesel identified its functional groups and the composition of its fatty acid methyl esters, respectively. Regression analysis revealed strong correlations between process variables and responses, with high R2 values indicating a good fit for most models and illustrated the interaction of variables influencing weight recovery, ash, and fixed carbon. Beyond its performance, this study highlights biodiesel's role as a sustainable and effective alternative to conventional, non-renewable collectors for graphite flotation, offering both efficacy and significant environmental advantages.