Flotation tests with a mix of two natural oils as apatite collectors

Abstract

It is essential to use natural, non-polluting and low-cost reagents in froth flotation in order to achieve a more sustainable and environmentally friendly process in mineral industry. Therefore, flotation tests in Hallimond tube were carried out with high purity apatite crystals using a mixture of a Brazilian fruit (Macaúba) and seed oil (Jatropha Curcas). The tests were carried out at pH 8, using a collector dosage of 2.5 mg/L. The oils were mixed at five different ratios (0:100, 25:75, 50:50, 75:25, and 100:0). The synthetic fatty acid mix called Flotigam 5806, from Clariant, an industrially adopted collector was used as benchmark. Macaúba oil, which is the richest in oleic acid, promoted floatability of apatite similar to Flotigam 5806 (almost 92%) and quite superior to Jatropha oil. One explanation for the low performance of collector based on pure Jatropha oil could be due to its lower content of oleic acid. However, since the Jatropha oil has a lower cost than Macaúba oil, the resulting mixture of the two oils in a ratio of 90:10 (Macaúba: Jatropha) promoted the reduction of collector final cost (8% lower than pure Macaúba oil and 44 % lower than Flotigam 5806) while maintaining the floatability of apatite similar to Flotigam 5806 and pure Macaúba oil. However, prior to application at industrial scale it is recommended to use more laboratory tests using real ore from the plant.