EDTA effect on the removal of Cu(II) onto TiO2.
The adsorption of Cu(II) and Cu(II)-EDTA onto TiO2 with variations in the pH, concentration, and molar ratio of Cu(II) to EDTA has been studied. The adsorption of Cu(II) and Cu(II)-EDTA onto TiO2 showed typical cationic- and anionic-type behavior, respectively. The removal of Cu(II) in an EDTA-excess system was less than that in an equimolar Cu(II)/EDTA system due to the competitive adsorption of EDTA and Cu(II)-EDTA onto the TiO2. The removal of Cu(II) was favorable at low pH for both the equimolar and EDTA-excess systems, while significant Cu(II) removal was observed over the entire pH range in a copper-excess system. For model predictions, the MINTEQA2 program employing an inner-sphere complexation and a diffuse layer model was used; the surface complexes used included Ti(OH2)OCu+, Ti(OH)EDTAH2-(2), and Ti(OH)EDTACu2-.
Yang
Jae-Kyu
JK
Environmental Technology Division, LG Environmental Strategy Institute, 120-749 Seoul, South Korea.
Lee
Seung-Mok
SM
D000327:Adsorption; D003300:Copper / Q000737:chemistry*; D004492:Edetic Acid / Q000737:chemistry*; D004785:Environmental Pollutants; D004787:Environmental Pollution / Q000517:prevention & control*; D006863:Hydrogen-Ion Concentration; D008958:Models, Molecular; D014025:Titanium / Q000737:chemistry*; D014866:Waste Products
D004785:Environmental Pollutants; D014866:Waste Products; C009495:titanium dioxide; D003300:Copper; D004492:Edetic Acid; D014025:Titanium