Processing of banded magnetite quartzite (BMQ) ore using flotation techniques

Recovery of iron values from banded magnetite quartzite (BMQ) ore by direct and reverse flotation technique is presented. In direct flotation, with oleic acid as the collector, the iron grade in the concentrate that could be achieved is limited to 57% Fe from a feed containing similar to 47% Fe. The difficulty of concentrating iron values by direct flotation technique is due to the fine coating of iron hydroxide over the particles at alkaline pH. In reverse flotation, better selectivity and collectability could be achieved using dodecylamine chloride as the collector. A statistical modeling approach called response surface methodology has been undertaken to optimize the reverse flotation process to maximize the iron grade and recovery. All the experiments have been conducted as per the central composite rotatable design (CCRD) taking collector, frother, depressant and pH as the factors. The program predicted 64.68% Fe with 66.38% recovery at a dodecylamine concentration of 271.88 g/T, MIBC: 40 g/t, starch: 400 g/T and at pH 9.5, which is also validated by the experimental results. (C) 2014 Elsevier BM. All rights reserved.