The aim of this study was to understand the effects of pH (5, 6, 7, 8, 9) and activated carbon (AC) concentration (0.01, 0.1, 1, 10, 100 g/L) on the removal of a colloidal solution of nanoparticles (NPs) (ZnO + CuO) using AC in batch kinetic studies. Results revealed that adsorption capacities of AC for Zn and Cu (individually) were 0.9 ± 0.028 mg/g (91.3% removal) and 0.95 ± 0.036 mg/g (95.6% removal) in deionized water and 0.6 ± 0.038 mg/g (78% removal) and 0.75 ± 0.078 mg/g (83% removal) in wastewater at pH 8 (Zn) and pH 6 (Cu) respectively. In a colloidal solution mixture of zinc oxide nanoparticles (ZnONPs) and copper oxide nanoparticles (CuONPs), adsorption capacity of AC for Zn in deionized water was 0.71 ± 0.051 mg/g (74.7% removal) and in wastewater was 0.576 ± 0.019 mg/g (69% removal) and for Cu in deionized water was 0.82 ± 0.017 mg/g (81.2% removal) and in wastewater was 0.6 ± 0.032 mg/g (71.5% removal). Overall, this study provided a detailed analysis of the removal capacity of AC and indicated that AC can be used as an efficient adsorbent filter for removing engineered NPs like ZnONPs and CuONPs (single and mixture) from water. As there is a need for removing NPs from wastewater, removal of NPs using an AC-based adsorptive-filter might become a promising method.
This study tested the feasibility of adsorptive removal of ZnO nanoparticles using activated carbon from wastewater. The effects of pH (5, 6, 7, 8, and 9) and nanoparticle/activated carbon concentration ratios (10, 1, 0.1, 0.01, and 0.001) on the removal were studied in batch kinetic studies in both deionized water and wastewater. The adsorption capacity of activated carbon for ZnO nanoparticles were found to be 9.3 ± 0.8 mg/g (93% removal) and 8.2 ± 3.7 mg/g (85% removal) at 640 and 780 min in deionized and wastewater respectively at optimum conditions (pH 8; 10g/L activated carbon concentration, 100mg/L ZnO nanoparticle concentration). The rate constant was lowest at ratio 0.01 and pH 8, and highest at ratio 10 and 1 and pH 5 and 6. Pseudo-second-order and the Weber-Morris model best described the adsorption process. Characterization analysis also confirmed the deposition of ZnO nanoparticles onto activated carbon. Overall activated carbon successfully removed ZnO nanoparticles using the adsorptive process.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.