Molecular insights into the interaction mechanism of triethylenetetramine target-deposited quartz from smithsonite in carbonate ionic liquids and its adsorption on minerals.

• Selective depression of quartz flotation by 20 mg/L of TETA at pH 10 was reduced from 92.2 % to 22.5 % in carbonate ionic liquid. • ICP and zeta potentials revealed that selectively adsorbed TETA altered the setting on the quartz surface to the preferential adsorption of NaOL on the smithsonite surface. • XPS and QCM-D support that TETA effectively forms new complexes with Zn 5 (OH) 6 (CO 3) 2 (s) and chemisorbs at the quartz interface. • TETA's N hybridizes to generate covalent bonds with Zn on the Zn-quartz surface and ionic bonds with Zn on the smithsonite. In order to induce alterations in the mineral surface's hydrophobicity and subsequently separate smithsonite from quartz, the current study introduces an innovative amine depressant termed triethylenetetramine (TETA). Micro-flotation experiments clearly demonstrated that adding a relatively modest dosage (20 mg/L) of TETA at pH 10 reduced the recovery of quartz from 92.2 % to 22.5 % without reducing the recovery of smithsonite. ICP-OES and zeta potentials revealed that TETA selectively adsorbed on the quartz surface effectively reduced Zn2+ dissolution and altered the setting of the quartz surface to preferentially adsorb NaOL on the smithsonite surface. X-ray photoelectron spectroscopy (XPS) and Quartz crystal microbalance with dissipation (QCM-D) analyses support that TETA is more susceptible to Zn atoms in Zn 5 (OH) 6 (CO 3) 2(s) through a bonding process and preferentially chemisorbs on the quartz surface to the exclusion of Zn-CO 3 on the smithsonite surface. Density functional theory (DFT) calculations revealed that electron acceptance by Zn and electron loss by N resulted in hybridization reactions between Zn 2 s, 3d, 4p and N 2p orbitals to form stable Zn-N covalent bonds. Chemical bonds characterized by ionic bonding were formed between TETA and Zn atoms on the cleavage plane of smithsonite, which led to the susceptibility of TETA adsorption on the surface of smithsonite to be broken. [ABSTRACT FROM AUTHOR]