Development and potential applications of nanomaterials for arsenic removal from contaminated groundwater.

Abstract: In this study, a magnetic nanomaterial was used for the binding of anionic arsenic species from contaminated groundwater. Iron oxide (Fe3O4) magnetic nanoparticles (NPs) and the surface modified Fe3O4 NPs with 3-aminopropyl-triethoxysilane (3-APTES), Trisodium citrare (TSC) and Chitosan were synthesized with the co-precipitation method. Structural characterizations showed that the four kinds of NPs had different sizes an average particle range size of 15-20 nm was observed with Transmission Electron Microscopy. X-ray diffraction was used to identify the crystalline structure of synthesized Fe3O4 and surface modified NPs. Molecular structure and functional groups present in synthesized magnetic NPs Fe3O4 were identify with infrared analysis. The synthesized Fe3O4 NPs and surface coated NPs were used for determine the binding capacity of Arsenic ions from the synthetic groundwater. The binding of As(III) increased as the dissolved As(III) concentration increased in the solution. From the experiments it was found chitosan-coated NPs are best than other coated and uncoated NPs for arsenite removal from the solution. It was found that if only As(III) ions were present in the water without other anions and cations the binding capacity of the magnetic NPs is very high. The binding capacity of As ions was decreased with presence of other anions and cations in the groundwater because they interfere with arsenic binding sites which presence on the magnetic NPs.