The effect of physical and chemical properties of diluent on copper solvent extraction by CP150

Effective parameters on diluent quality in copper solvent extraction circuit have been investigated. Several experiments were carried out with 10% CP150 as extractant in 90% diluent with different aromatic contents (5-35%). Performance parameters such as kinetics, selectivity, separation time and entrainment have showed that, by increasing the aromatic content in diluent, the copper extraction rate, separation time and losses of extractant by entrainment have been decreased; If aromatic content increased from 5 to 35 %, entrainment and separation time declined about 50 % while aromatic content appears to help suppress iron co-extraction. Batch experiments repeated by several composition prepared from various ratios of Kerosene, Reasol 8401 and Reasol 8411. Results indicated that aromatic content of diluent must be controlled as well as physical properties especially where a mixture of several solvents are used as diluent. Low diluent viscosity improve the kinetics because of high phase dispersion; if diluent viscosity increase from 2.09 to 2.29 cSt, extraction rate in 30 seconds is reduced by 30%. Higher density and surface tension result in organic phase entrainment and solvent loss; so that, by increasing in surface tension from 26 to 27/3 mN/m, entrainment enhanced by almost 100%. However, high interfacial tension, density and viscosity enhanced Cu/Fe separation; if diluent density rise up 35 Kg/m3, Cu/Fe transmission factor is declined tenfold.