Transport of surface-modified iron nanoparticle in porous media and application to arsenic(III) remediation |
| |
Authors: | Sushil Raj Kanel Dhriti Nepal Bruce Manning Heechul Choi |
| |
Institution: | (1) Department of Environmental Science and Engineering, Gwangju Institute of Science and Technology (GIST), 1-Oryong-dong, Buk-gu, 500-712, Gwangju, The Republic of Korea;(2) Department of Materials Science and Engineering, Gwangju Institute of Science and Technology (GIST), 1-Oryong-dong, Buk-gu, 500-712, Gwangju, The Republic of Korea;(3) Department of Chemistry and Biochemistry, San Francisco State University, 1600 Holloway Avenue, San Francisco, California 94132, USA |
| |
Abstract: | The surface-modified iron nanoparticles (S-INP) were synthesized, characterized and tested for the remediation of arsenite
(As(III)), a well known toxic groundwater contaminant of concern. The S-INP material was fully dispersed in the aqueous phase
with a particle size distribution of 2–10 nm estimated from high-resolution transmission electron microscopy (HR-TEM). X-ray
photoelectron spectroscopy (XPS) revealed that an Fe(III) oxide surface film was present on S-INP in addition to the bulk
zero-valent Fe0 oxidation state. Transport of S-INP through porous media packed in 10 cm length column showed particle breakthroughs of 22.1,
47.4 and 60 pore volumes in glass beads, unbaked sand, and baked sand, respectively. Un-modified INP was immobile and aggregated
on porous media surfaces in the column inlet area. Results using S-INP pretreated 10 cm sand-packed columns containing ∼2 g
of S-INP showed that 100 % of As(III) was removed from influent solutions (flow rate 1.8 mL min−1) containing 0.2, 0.5 and 1.0 mg L−1 As(III) for 9, 7 and 4 days providing 23.3, 20.7 and 10.4 L of arsenic free water, respectively. In addition, it was found
that 100% of As(III) in 0.5 mg/L solution (flow rate 1.8 mL min−1) was removed by S-INP pretreated 50 cm sand packed column containing 12 g of S-INP for more than 2.5 months providing 194.4
L of arsenic free water. Field emission scanning electron microscopy (FE-SEM) showed S-INP had transformed to elongated, rod-like
shaped corrosion product particles after reaction with As(III) in the presence of sand. These results suggest that S-INP has
great potential to be used as a mobile, injectable reactive material for in-situ sandy groundwater aquifer treatment of As(III). |
| |
Keywords: | Nanoparticles Surfactants Arsenic In-situ treatment Environmental remediation |
本文献已被 SpringerLink 等数据库收录! |
|