METHOD TO SEPARATE COPPER FROM ZINC IN WEAKLY ACID SOLUTIONS Russian patent published in 1995 - IPC

FIELD: process of non-ferrous metals separation. SUBSTANCE: alkylphosphoric acid solution is pretreated with aqueous solution of copper hydroxide, which is produced by introduction of sodium hydroxide aqueous solution in a system being mixed. The system comprises organic solution of DEPHA and copper salt aqueous solution with 1:(5 - 1) water- to-organic phase ratio. Copper concentration in organic phase should be 35 - 40 per cent of total metal concentration in initial phase entering separation. Then zinc extraction by solution of DEPHA copper salt solution is performed through three or four stages. When impurities are presented in the solution to be separated extraction are performed in the presence of neutral alkylphosphates. Tributilphosphate or trioctylphosphineoxid amounted of 50 per cent of DEPHA by volume in organic solution are used as alkylphosphates. EFFECT: very effective separation of ferrous metals. 3 cl, 4 tbl