A bench-scale investigation of chrysocolla flotation using n-octanohydroxamate collector

Abstract

The flotation response of blended chrysocolla-sand samples using n-octanohydroxamate collector was investigated. Wet grinding, salinity, frother type and depressants were examined. A Copper recovery of 99.1% was achieved after wet grinding at pH 10, while the best copper grade was achieved after wet grinding at pH ~7. Using 80 g/t of a strong frother (IF4500A) did not result in a significant improvement in overall copper recovery, but it did lead to a faster recovery rate than when no additional frother was added. Sodium silicate as a depressant led to an improved concentrate grade, whereas using a tannic acid as a depressant did not significantly affect either recovery rate or grade. Using a short period flotation time resulted in higher copper grade and a lower iron grade. XPS was employed to characterise the surface composition and coverage of conditioned sand samples in the absence of chrysocolla.