Quantum chemistry assisted screening of zircon flotation collectors

•The quantum chemistry assisted screening of flotation reagents is accurate and feasible to oxide minerals.•The reaction-free energy can be a useful indicator of interface bonding intensity between collectors and surface targets.•The screened n-octyl phosphoric acid and octyl hydroxamic acid perform well in flotation tests of zircon. This technical note proposed a new approach to screen flotation reagents based on fast and accurate batch quantum chemistry calculations. Accordingly, the ethyl-functional group (EFG) data bank was used to calculate the reaction-free energy of solidophilic groups with possible metal hydroxide ions (the representatives of mineral surface sites). Then the obtained solidophilic groups possessing the best binding affinity with surface sites were linked with the C8 hydrocarbon chain to form the collectors [n-octyl phosphoric acid (nOPA), octyl hydroxamic acid (OHA)]. The flotation results showed that the nOPA and OHA had much better flotation performance than the octanoic acid. These results showed that the quantum chemistry-assisted rational screening and design of flotation reagents was accurate and feasible. This work can shed new light on screening new and novel flotation reagents with virtual screening techniques.