Activation mechanism of ammonium ions on sulfidation of malachite (-201) surface by DFT study

The activation mechanism of ammonium ions on the sulfidation of malachite (−201) was determined by density functional theory (DFT) calculations. Results of DFT calculations indicated that interlayer sulfidation occurs during the sulfidation process of malachite (−201). The absorption of both the ammonium ion and sulfide ion on the malachite (−201) surface is stronger than that of sulfur ion. After sulfidation was activated with ammonium ion, the Cu 3d orbital peak is closer to the Fermi level and characterized by a stronger peak value. Therefore, the addition of ammonium ions activated the sulfidation of malachite (−201), thereby improving the flotation performance.