Improving copper flotation recovery from a refractory copper porphyry ore by using ethoxycarbonyl thiourea as a collector

In this paper, N-propyl-N-ethoxycarbonyl thiourea (PECTU) collector was investigated to concentrate copper minerals from a refractory copper porphyry ore through bench-scale and industrial flotation tests. The flotation results indicated that PECTU had strongly collecting power for copper sulfide minerals and excellent selectivity against iron sulfide minerals under moderately alkaline conditions. Compared with sodium butyl xanthate (SBX), PECTU increased the grades and recoveries of Cu, Au and Mo in the copper concentrates, and performed the flotation separation of Cu/Fe sulfide minerals at cleaner pH ∼10.5 as well as decreased 2/3 lime consumption. The results of UV–visible measurements further demonstrated that PECTU could be used as a high selective collector for copper minerals. The experimentally obtained results have been explained from the structure–reactivity relationship of collector by density functional calculation.

Graphical abstractThe effects of cleaner times and cleaner pH values on the recoveries and grades of copper in Cu concentrates: PECTU, N-propyl-N-ethoxycarbonyl thiourea; SBX, sodium butylxanthate. The differential values Δ of Cu grades and recoveries between experimental and control system.Figure optionsDownload full-size imageDownload as PowerPoint slideResearch highlights► N-propyl-N-ethoxycarbonyl thiourea (PECTU) had moderately electron-donating power and strongly electron-accepting power. ► PECTU had excellent selectivity against iron sulfides. ► PECTU performed the Cu/Fe flotation separation at the cleaner pH ∼10.5 with improving Cu, Au and Mo recoveries.