Chitosan (CS)/Poly (vinyl alcohol)(PVA)/modified Graphene Oxide(MGO) nanocomposite as an excellent Super-adsorbent for Heavy metal ions Removal

Nanomaterials and nanocomposites have been recently received great attention in pollutant removal from the environment. In this study, nanocomposite based on chitosan/polyvinyl alcohol (CS/PVA) and modified-GO was prepared. The characteristics of the synthesized nanocomposite were analyzed, in each step, by field emission scaning electron microscopy (FESEM), Fourie Transform infrared spectroscopy (FTIR), and X-ray diffraction spectroscopy (XRD). Also, kinetick parameters were studied and it was understood that the Langmuir isotherm fitting was slightly better than that of Freundlich adsorption isotherm.Then, the effective parameters, such as: adsorbent amount, contact time, initial concentration of pollutant, temperature, and pH, were investigated on the sorption capacity and the lead ions removal. Under optimal conditions: ۵۰ ml of ۱ppm Pb۲+at pH=۶, T=۲۰°C, contact time=۳h, ۰.۰۲ g of nanocomposite containing ۱.۵%w/w of modified-GO, ۹۷.۵۶% ± ۰.۱۷۶(n=۷) of lead ions were removed from the wastewater of National Iranian Lead & Zinc Company. Additionally, the synthesized nanocomposite could act as a proper super-adsorbent and, under optimal conditions, could remove quantitatively Pb۲+, Cu۲+, Zn۲+, and Cd۲+ ions from the wastewater.

Keywords:

nanocomposite , Chitosan/polyvinyl alcohol matrix , modified graphene oxide , heavy metal ions removal.