DFT calculation of octyl hydroxamic acid and oleic acid and their flotation performance comparison on bastnaesite and fluorite

The density functional theory (DFT/B3LYP) calculation was carried out to analyse the geometric structure, frontier molecular orbital and Mulliken charge values of octyl hydroxamic acid (OHA) and oleic acid (OA) as well as their respective binding energy with Ca2+ and Ce3+ ions. Besides, pure mineral flotation was used to compare the flotation performances of OHA and OA for bastnaesite and fluorite. The DFT calculation results show that OHA anion has the highest binding atom charge, the strongest HOMO energy and the lowest EHOMO-LUMO energy gap, thus performing stronger electron donating ability and reactivity than OA; the binding energy strength decreases in such order as OHA-Ce, OA-Ce, OA-Ca and OHA-Ca. In other words, OHA has the biggest binding energy with Ce3+ and largest binding energy difference for Ca2+ and Ce3+ ions. The flotation results show that OHA has a stronger collection capacity and selectivity than OA, which is consistent with the DFT calculation results.
The density functional theory (DFT/B3LYP) calculation was carried out to analyse the geometric structure, frontier molecular orbital and Mulliken charge values of octyl hydroxamic acid (OHA) and oleic acid (OA) as well as their respective binding energy with Ca2+ and Ce3+ ions. Besides, pure mineral flotation was used to compare the flotation performances of OHA and OA for bastnaesite and fluorite. The DFT calculation results show that OHA anion has the highest binding atom charge, the strongest HOMO energy and the lowest EHOMO-LUMO energy gap, thus performing stronger electron donating ability and reactivity than OA; the binding energy strength decreases in such order as OHA-Ce, OA-Ce, OA-Ca and OHA-Ca. In other words, OHA has the biggest binding energy with Ce3+ and largest binding energy difference for Ca2+ and Ce3+ ions. The flotation results show that OHA has a stronger collection capacity and selectivity than OA, which is consistent with the DFT calculation results.