Williams Briceño’s research while affiliated with Universidad Católica del Norte (Chile) and other places

... Considering variation in the mineral feeding and the alternatives of leaching agents, two production campaigns are defined, as Mode 1 and Mode 2. Considering the values of variables/parameters presented in Table 1, analytical models were fitted for recovery versus time for copper oxides (Equation (2)) and copper sulfides (Equation (3)) minerals, leaching only H 2 SO 4 , and Cl − ions addition for sulfide minerals at concentration levels of 20 g/L (Equation (4)), 35 g/L (Equation (5)) and 50 g/L (Equation (6)). In addition, its assumption that in an infinite operating time the mineral recovery is equal because chalcocite and others secondary copper sulfides are not refractory to conventional leaching processes [30,51]. Copper recovery from oxides and sulfide minerals by adding only H 2 SO 4 is shown in Equations (2) and (3), while that copper recovery from sulfide minerals by adding H 2 SO 4 + Cl − at concentrations of 20, 35 and 50 g/L are shown in Equations (4)-(6), respectively, where the random variables of the models are Z, µ s , r and t (whose domain is indicated in Table 1), the parameters ε b , D Ae , ε 0 and ω were set from historical measurements and contrasted with the literature [50], and the mathematical fit parameters were calculated using least squares. ...

Reference:

Dynamic of Mining Systems: Impact of Cl Ion Concentration on Heap Copper Leaching Process at Industrial Scale