Development of Graphene Oxide based nano composites for water purification

DEVELOPMENT OF GRAPHENE OXIDE BASED NANO COMPOSITES FOR WATER PURIFICATION Contamination of drinking water sources by flouride ions has caused serious health issues. Therefore, it is important to develop fluoride ion filtering material using nanotechnology. A novel Al and Ce coated hydroxyapatite (HAp) nanocomposite was developed for the efficient adsorption of fluoride ions using wet chemical precipitation method. It was further coated with graphene oxide (GO), which resulted in four different morphologies within the nanocomposite. The synthesized Al-Ce-HAp and Al-Ce-HAp-GO nanocomposites were characterized using Fourier Transformed Infrared Spectroscopy (FT-IR), power X-ray Diffraction (XRD) and Scanning Electron Microscopy (SEM). It confirmed that Al, Ce, and HAp were sucessfully coated on GO. Detailed adsorption studies of both Al-Ce-HAp and Al-Ce-HAp-GO nanocomposites were carried out for fluoride ions at 300 K. The maximum adsorption capacity was observed for Al-Ce-HAp-GO nanocomposite of 16.81 mg/g, under the conditions of pH 5.36 at 300 K within 60 minutes. The adsorption of fluoride ions was evaluated according to both Langmuir and Freundlich adsorption isotherm models for both Al-Ce-HAp and Al-Ce-HAp-GO nanocomposites. The equilibrium adsorption data were best fitted with the Langmuir adsorption isotherm model for both composites. According to the results obtained from the adsorption studies, Al-Ce-HAp-GO was identified as the best adsorbent for fluoride adsorption compared to Al-HAp and Al-Ce-HAp nanocomposites. Keywords: graphene oxide, hydroxyapatite, adsorption, nano composite