Selective removal of copper(II) from natural waters by nanoporous sorbents functionalized with chelating diamines.
Copper has been identified as a pollutant of concern by the U.S. Environmental Protection Agency (EPA) because of its widespread occurrence and toxic impact in the environment. Three nanoporous sorbents containing chelating diamine functionalities were evaluated for Cu(2+) adsorption from natural waters: ethylenediamine functionalized self-assembled monolayers on mesoporous supports (EDA-SAMMS), ethylenediamine functionalized activated carbon (AC-CH(2)-EDA), and 1,10-phenanthroline functionalized mesoporous carbon (Phen-FMC). The pH dependence of Cu(2+) sorption, Cu(2+) sorption capacities, rates, and selectivity of the sorbents were determined and compared with those of commercial sorbents (Chelex-100 ion-exchange resin and Darco KB-B activated carbon). All three chelating diamine sorbents showed excellent Cu(2+) removal (approximately 95-99%) from river water and seawater over the pH range 6.0-8.0. EDA-SAMMS and AC-CH(2)-EDA demonstrated rapid Cu(2+) sorption kinetics (minutes) and good sorption capacities (26 and 17 mg Cu/g sorbent, respectively) in seawater, whereas Phen-FMC had excellent selectivity for Cu(2+) over other metal ions (e.g., Ca(2+), Fe(2+), Ni(2+), and Zn(2+)) and was able to achieve Cu below the EPA recommended levels for river and sea waters.
Chouyyok
Wilaiwan
W
Pacific Northwest National Laboratory, Richland, Washington 99352, USA.
Shin
Yongsoon
Y
Davidson
Joseph
J
Samuels
William D
WD
LaFemina
Nikki H
NH
Rutledge
Ryan D
RD
Fryxell
Glen E
GE
Sangvanich
Thanapon
T
Yantasee
Wassana
W
D000327:Adsorption; D002413:Cations, Divalent / Q000737:chemistry; D002614:Chelating Agents / Q000737:chemistry*; D003300:Copper / Q000302:isolation & purification*; D003959:Diamines / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D049329:Nanostructures / Q000737:chemistry*; D016062:Porosity; D045483:Rivers / Q000737:chemistry*; D012623:Seawater / Q000737:chemistry*; D012996:Solutions; D013696:Temperature; D014874:Water Pollutants, Chemical / Q000302:isolation & purification*
D002413:Cations, Divalent; D002614:Chelating Agents; D003959:Diamines; D012996:Solutions; D014874:Water Pollutants, Chemical; D003300:Copper