Activation mechanism of copper ion in arsenopyrite flotation in high pH value

Abstract

Arsenopyrite exhibits good floatability after copper activation in a high alkaline environment, leading to harder removal of arsenopyrite from concentrate. In this paper, the activation mechanism of copper ion in arsenopyrite flotation was studied using flotation test, surface adsorption experiments, contact angle measurements, X-ray photoelectron spectrometer (XPS), time-of-flight secondary ion mass spectrometry (ToF-SIMS) and analysis of Eh-pH diagrams of the FeAsS-H2O system and Cu-FeAsS-H2O system. It can be seen from the results that arsenopyrite participates in the chemical reaction as a reducing agent, the copper formed by Cu2S remained on the mineral surface, and the oxidation state of elements Fe, As and the hydrophilic substance such as arsenate, arsenite and ferric hydroxide was decreased, after activated by copper ions. These phenomenon lead floatability of arsenopyrite activated in alkaline environment.