The synergistic mechanism of solvent extraction of gold in HCI media with TOA and TOPO

The mechanism of synergistic extraction of gold in HCl media was researched with tri-n-octyl amine(TOA) and tri-n-octyl phospine oxide(TOPO). It was determined that the composition of synergistic extract is (TOAHTOPO) AuCl₄; the constant of synergistic extracting equilibrium is 10^9.20; and the synergistic reaction is exothermic with − 17.187 kJ/K· mol of ΔH ₂₉₈. The extraction mechanism was also studied by the IR-spectra and UV-spectra. It is found that the extraction mechanism belongs to ion-association type. Synopsis of the first author Yang Tianzu, professor, born in April 1958, majoring in the metallurgy of precious metals and coordination chemistry in hydrometallurgy.