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Talc is an industrial mineral that is widely used. It is always associated with other minerals, which determine the quality of talc samples for industrial purposes. Various operating variables control the natural floatability of talc. For enhancement of talc flotation, sodium hexametphosphate is used as a depressant for associated gangue minerals. In addition, oleic acid (in an equal mixture with kerosene) is used as an anionic collector. The results presented in this paper provided useful and important information on how to improve the quality of talc for industrial uses. The optimum conditions were obtained at pH = 11, depressant dosage = 1.0 kg/t, collector dosage = 1.2 kg/t and pulp density = 200 g/L. At these conditions, SiO 2 assay increased from 54.10% to 54.94%, MgO assay increased from 29.90% to 31.76%, CaO decreased from 0.80% to 0.42%, Al 2 O 3 decreased from 5.50% to 3.11%, Fe 2 O 3 decreased from 8.20% to 7.24%, the whiteness increased from 75.4% to 83.7%, and the loss on ignition decreased from 6.64% to 5.21%. The mass recovery of final concentrate was 92.4%. The component recoveries of SiO 2 and MgO (the major constituents of talc) in the final concentrate were 93.8% and 98.2%, respectively. More improvement of talc quality was obtained by leaching of final concentrate of flotation with 10% dilute hydrochloric acid. The mass recovery of final product was about 85% of initial feed. In this final product, Fe 2 O 3 decreased to 3.12%, CaO decreased to 0.38%, and Al 2 O 3 decreased to 3.01%. The assay of SiO 2 increased to 58.96%, MgO percent was nearly the same, the whiteness increased to 88.5%, and the loss on ignition decreased to 4.03%. The final product is suitable for many industrial uses such as low-loss electronics (a type of ceramics), paints, rubber, plastics, roofing, textiles, refractories, insecticides and coating of welding rods.

Phosphates are vital nonrenewable resources. The treatment of phosphate ore wastes of El-Nasr Mining Company, Sepaeya, Egypt aims to upgrade P 2 O 5 percent, adds a new economic value, development of the Egyptian national income, and aids to clean the mine district. The main aim of this paper is to compare different processing alternatives methods to concentrate and upgrade of phosphate ore tailings assayed 18.37% of El-Nasr Mining Company, Sepaeya, Egypt. The concentration of wastes not only add an economic value but also safe the human, animals, and plants. Two options of sizes obtained from grinding and sieving were separated to obtain the highest grade of P 2 O 5 with the greatest recovery. The first option (i.e. sizes below 100 µm) gave P 2 O 5 percent of 23.88%, P 2 O 5 recovery of 42.37%, and weight recovery equals to 33.68%. The second option (i.e. sizes below 160 µm) gave P 2 O 5 percent of 22.52%, P 2 O 5 recovery of 53.25%, and weight recovery equals to 44.88%. The calcination process raised P 2 O 5 to 22.4 with weight recovery 83.75%, and P 2 O 5 recovery of 99.10%. Leaching process using acetic acid gave the best results at the following conditions: a)solid to liquid ratio 15% where the percent of P 2 O 5 raised from 18% to 22.23% with weight recovery about 86%, b) Agitation time 15 minutes where the percent of P 2 O 5 raised from 18% to 22.35% with weight recovery about 86%, c) Agitation speed 1200 rpm where the percent of P 2 O 5 increased from 18% to 22.23% with weight recovery about 86%, d) Acid to ore ratio 16.7% where the percent of P 2 O 5 increased from 18% to 21.44% with weight recovery about 88.7%. The leaching process on size -100 µm raised P 2 O 5 % from 23.88% to 28.44% with weight recovery 84%. The weight recovery and P 2 O 5 recovery with respect to the original feed were 28.29% and 42.39%, respectively.