Application of Zero-Valent Iron Nanoparticles for the Removal of Aqueous Zinc Ions under Various Experimental Conditions |
| |
| Authors: | Wen Liang Chaomeng Dai Xuefei Zhou Yalei Zhang |
| |
| Affiliation: | 1. State Key Laboratory of Pollution Control and Resources Reuse, Tongji University, Shanghai, China.; 2. College of Civil Engineering, Tongji University, Shanghai, China.; RMIT University, Australia, |
| |
| Abstract: | Application of zero-valent iron nanoparticles (nZVI) for Zn2+ removal and its mechanism were discussed. It demonstrated that the uptake of Zn2+ by nZVI was efficient. With the solids concentration of 1 g/L nZVI, more than 85% of Zn2+ could be removed within 2 h. The pH value and dissolved oxygen (DO) were the important factors of Zn2+ removal by nZVI. The DO enhanced the removal efficiency of Zn2+. Under the oxygen-contained condition, oxygen corrosion gave the nZVI surface a shell of iron (oxy)hydroxide, which could show high adsorption affinity. The removal efficiency of Zn2+ increased with the increasing of the pH. Acidic condition reduced the removal efficiency of Zn2+ by nZVI because the existing H+ inhibited the formation of iron (oxy)hydroxide. Adsorption and co-precipitation were the most likely mechanism of Zn2+ removal by nZVI. The FeOOH-shell could enhance the adsorption efficiency of nZVI. The removal efficiency and selectivity of nZVI particles for Zn2+ were higher than Cd2+. Furthermore, a continuous flow reactor for engineering application of nZVI was designed and exhibited high removal efficiency for Zn2+. |
| |
| Keywords: | |
|
|
