Lecithin as an ecofriendly amphoteric collector foaming agent for the reverse flotation of phosphate ore

Abstract

The development of more widely available, effective, economical, and environmentally friendly reagents is one of the major prospects of the phosphate industry. In this work, an eco-friendly reagent based on lecithin was successfully elaborated and adopted as a new amphoteric collector and frother, both for the flotation of phosphate ore. The proposed reagent was evaluated regarding its physicochemical properties (critical micelle concentration CMC, acidity index, composition) by conductivity, and ultra-high performance liquid chromatography (UHPLC). The performance of the collector in phosphate ore flotation was investigated by means of X-ray diffraction (XRD), X-ray fluorescence (XRF), scanning electron microscope (SEM) and Fourier transform infrared (FTIR) spectrophotometry. Furthermore, the results of FTIR, SEM, and XRD analyses show that the lecithin collector has a good ability to collet calcite, dolomite and quartz. It has also been observed that francolite and quartz can be successfully separated at a pH of 5 and a lecithin concentration of 40 mg/L. Similarly, an effective separation of francolite and carbonate gangue (dolomite and calcite) can be achieved at pH 8.5 and 40 mg/L lecithin concentration. In addition, flotation tests and X-ray fluorescence show that the required quality of phosphate concentrate was obtained at 31.05% P2O5 with a recovery of 98.21% at pH 5. Similarly, 32.39% P2O5 grade was obtained with 96% recovery at pH 8.5. Thus, the results obtained suggest that lecithin has significant potential as an efficient and environmentally friendly collector for the development of selective flotation in phosphate concentration circuits.