ABSTRACT
The geochemical characteristics of all these potential adsorbents were examined and included SEM combined with Energy Dispersive X-ray analysis (EDX) and X-ray fluorescence spectrometry (XRF) analysis. The EDX analyses were done simultaneously with the SEM in order to determine the chemical and mineralogical composition of the prepared adsorbents. The major oxide constituents of the adsorbents were determined by XRF analysis. Fourier Transform Infrared Spectroscopy (FTIR) was used to identify the chemical bonds in the molecules by producing an infrared absorption. By interpreting the infrared absorption spectrum, the chemical bonds present in the adsorbents were determined. XRD patterns, XRF data, SEM images and FTIR spectra indicated that NOIS is highly amorphous in nature and the major composition is iron oxides which can facilitate adsorption of arsenic from aqueous solution. XRD patterns and FTIR spectra confirmed quartz as the major constituent of sand. XRD patterns indicated that both red soil and murum contained
1 INTRODUCTION
Arsenic (As) contamination of shallow groundwater is a widespread health threat in the developing countries. A relatively recent arsenic screening and surveillance program in the Brahmaputra Floodplain in Assam, a state in the northeastern part of India revealed that 30% sources out of total 56,180 sources tested were above WHO limits of 10 ppb and 8% sources were above 50 μg/L (Mahanta et al. 2011). Given these facts, it is crucial to develop arsenic removal filtration device which can be easily fabricated locally with locally available materials constituting the media, is efficient, sustainable yet easily operable, and hence, acceptable by the community. The present work proposes a filter with locally available material viz. Naturally Oxidized Iron Scrap (NOIS), red soil, murum (a type of lateritic soil) and sand for arsenic remediation at the field level.
