Escondida process

Duyvesteyn, W. P. C. Sabacky, B. J. The Escondida process for copper concentrates. Extr. Metall. Copper, Nickel Cobalt, Proc. Paul E. Queneau Int. Symp. 1993, 1, 881-910. 

Copper SX has also been successfully achieved using leach systems other than sulfuric acid. The Arbiter plant in Anaconda, Montana, treated an ammoniacal leach liquor from a sulfide concentrate using LIX 64N (Anon 1973). More recently, BHP Minerals (now BHPBilliton) developed the Escondida process in which copper concentrates are leached with anunonia and ammonium sulfate, and then purified by SX... 

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