This study attempts to assess the contribution of entrainment and true flotation in the overall recovery by the laboratory tests performed on a natural complex sulfide ore, provided by la Compagnie Minière des Guemassa (Morocco), and the effect of two different collectors, Potassium Amyl Xanthate (PAX) and Sodium di-isobutyl di-thiophosphinate (Aerophine 3418A), on the two contributions. Overall recovery and true recovery were fitted to first kinetic model and modified flotation parameters were calculated to measure of flotation separation selectivity of chalcopyrite, galena and sphalerite over gangue and pyrrhotite. To estimate the entrainment, Ross method was the most suitable in the case of complex sulfide ore with high content of pyrrhotite. Trahar method overestimates the effect of entrainment.

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Silver was recovered selectively by ionic flotation from photographic bleachfix solutions containing Fe-EDTA. The collector chosen was sodium di-isobutyldithiophosphinate (Aerophine 3418A). which gives a well flocculated precipitate containing 34% Ag and floats in less than 5 minutes. For a collector concentration ranging between once and twice the silver concentration, the recovery rates reach 99% and they are not significantly affected by a pH variation from 4 to 8 and a temperature increase between 20 and 40°C. The desilvered solutions can be recycled in photographic processing, and pure metallic silver at 99.9% Ag is easily obtained from the precipitate phase by thermal decomposition at 900°C.

Copper production from ores or sulphide concentrates is classically realized by pyrometallurgical route. In this study, hydrometallurgical treatment of a copper sulphide concentrate, provided by Hajar Mine (ONA-Group, Morocco), was tested by using a mixture of nitric and hexafluorosilicic acids. Copper is present in the solid product as chalcopyrite and its amount is 28.1 % by weight. Leaching stage allows to dissolve more than 90% of copper witch is accompanied, in the same averages, by Zn and Fe. The leach solution obtained has pH = 0.6 and Eh = 580 mV/ENH and contains 19.3 g/L Cu, 18.1 g/L Fe, 4.5 g/L Zn and 0.03 g/L Pb. The recovery of copper from this leach solution was curried out by solvent extraction using Lix 984, diluted in Escaid 110. McCabe - Thiele distribution isotherms showed that at pH 1.7 total and selective copper extraction can be realized with Øo:Øa =1.5:1 in 3 extraction stages. Stripping of the loaded copper by treating the organic phases was easily obtained by a sulphuric acid solution