title: Mutual effects of copper and phosphate on their interaction with γ-Al2O3: combined batch macroscopic experiments with DFT calculations.
abstract: The mutual effects of Cu(II) and phosphate on their interaction with γ-Al(2)O(3) are investigated by using batch experiments combined with density functional theory (DFT) calculations. The results of batch experiments show that coexisting phosphate promotes the retention of Cu(II) on γ-Al(2)O(3), whereas phosphate retention is not affected by coexisting Cu(II) at low initial phosphate concentrations (≤ 3.6 mg P/L). Cu-phosphate aqueous complexes control Cu(II) retention through the formation of type B ternary surface complexes (where phosphate bridges γ-Al(2)O(3) and Cu(II)) at pH 5.5. This deduction is further supported by the results of DFT calculations. More specifically, the DFT calculation results indicate that the type B ternary surface complexes prefer to form outer-sphere or monodentate inner-sphere binding mode under our experimental conditions. The enhancement of phosphate retention on γ-Al(2)O(3) in the presence of Cu(II) at high initial phosphate concentrations (>3.6 mg P/L) may be attributed to the formation of 1:2 Cu(II)-phosphate species and/or surface precipitates. Understanding the mutual effects of phosphate and Cu(II) on their mobility and transport in mineral/water environments is more realistic to design effective remediation strategies for reducing their negative impacts on aquatic/terrestrial environments.
authors.affiliation: Key Laboratory of Novel Thin Film Solar Cells, Institute of Plasma Physics, Chinese Academy of Sciences, P.O. Box 1126, 230031 Hefei, PR China.
authors.forename: Xuemei
authors.initials: X
authors.lastname: Ren
authors.forename: Shitong
authors.initials: S
authors.lastname: Yang
authors.forename: Xiaoli
authors.initials: X
authors.lastname: Tan
authors.forename: Changlun
authors.initials: C
authors.lastname: Chen
authors.forename: Guodong
authors.initials: G
authors.lastname: Sheng
authors.forename: Xiangke
authors.initials: X
authors.lastname: Wang
mesh_terms: D000327:Adsorption; D000537:Aluminum Oxide / Q000737:chemistry*; D003300:Copper / Q000737:chemistry*; D010710:Phosphates / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000737:chemistry*
chemical_list: D010710:Phosphates; D014874:Water Pollutants, Chemical; D003300:Copper; D000537:Aluminum Oxide