In this study, possible separation of chromite from serpentine in fine sizes using a magnetic carrier was investigated as a function of pH, dodecylamine (DDA) dosage, and amount of magnetite. First, the zeta potentials of minerals were determined in the absence and presence of DDA, and then magnetic carrier experiments were performed in conditions based upon the zeta potential results. Experiments revealed that chromite could be separated from serpentine with a 96.8% recovery under the experimental conditions of 4 x 10 −4 M DDA, 25 mg magnetite, and at pH 12. In the case of artificial mixtures of chromite and serpentine minerals, chromite concentrate containing 49.7% Cr 2 O 3 was obtained with 82.8% recovery from a feed containing 27.00% Cr 2 O 3. As a result of FTIR studies, physical adsorption of DDA on minerals was confirmed. It was also found that DDA adsorption on chromite was higher than those of serpentine and magnetite. FTIR studies performed with chromite+magnetite and serpentine+magnetite mixtures revealed that DDA adsorption on serpentine declined significantly while DDA adsorption on chromite slightly increased.

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Negatively Biased Flotation Column (NBFC) is a tool, which is developed for the flotation of coarse-sized ores. Unlike the conventional flotation column, in this column, there is no froth zone and wash-water is usually not used. Therefore, hydrodynamically entrainment of fine-sized particles into the concentrate is possible, and this may result in a decrease in the grade or yield of the concentrate. In this study, operating parameters that can affect the entrainment of fine-sized particles were investigated. Calcite with a grade of 99.4% (CaCO3) and chromite concentrates with a grade of 54.8% (Cr2O3) were used in the experiments. Parameters such as superficial water flowrate, particle size, air flow rate, frother dosage and particle density were used in the experiments. As a result of the experiments, it was determined that the amount of entrainment increased as the particle size and density decreased, and decreased with increasing superficial water flowrate, air flow rate and frother dosage.

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