Removal of ZnO and CuO Nanoparticles from Water Using an Activated Carbon Column

Abstract

Efficient removal of nanoparticles (NPs) is particularly important in view of the increasing long-term persistence and evidence of considerable ecotoxicity of some nanoparticles. The aim of this study was to understand the effects of flowrate (.5, 1, and 1.5 mL/min), concentration (1, 1, and 1 mg/L), and the type of nanoparticles (ZnO, CuO, and ZnO+CuO) on the removal of the nanoparticles in an activated carbon column. Flowrate, concentration of NPs, and type of NPs were found to influence the removal at room temperature. Complete removals of both ZnONPs and CuONPs in both single and binary suspensions from water were achieved. Breakthrough was achieved after treating 3 L of water for nearly 5 h for concentrations of 1 and 1 mg/L of ZnONPs and CuONPs. The breakthrough was reached faster for Cu (49.5 h) than Zn (53 h). More work is required to understand the effect of water quality on the removal, to develop methods for quantifying the concentration of nanoparticles after any kind of nanoparticle-water interaction, and to understand the fate and removal mechanism of NPs in the column.