Fabrication of novel magnetic graphene oxide nanoadsorbent from Strychnous potatorum seeds for enhanced removal of chromium from wastewater

Enhanced removal of chromium from wastewater using magnetic graphene oxide nanoadsorbent

Abstract

The main aim of the study is to synthesize graphene oxide from natural source (by utilizing Strychnous potatorum seeds) and composite with iron oxide to form magnetic graphene oxide (MGO) which was applied as adsorbent for removal of chromium from wastewater. The prepared MGO adsorbent was characterized by FTIR, XRD, VSM, UV-visible and SEM to examine its structural, morphology, elemental and chemical composition. The average particle size of MGO from SEM image is 47.2 nm and analysis results showed the successful oxidation of GO and well distribution of magnetic iron oxide particles onto GO. Batch method was opted for adsorption process and the operation parameters were optimized. The adsorbent MGO exhibits maximum removal rate of 97.1% for chromium under optimized conditions. The adsorbent dose of 10 mg shows maximum efficiency in the adsorption process. Adsorption Isotherm and kinetic behavior were investigated and founded that Freundlich adsorption isotherm model were well suited for chromium (R²=0.996) and the adsorption behavior were well explained by pseudo second order which followed by chemisorption. The maximum adsorption capacity (q_max) exhibited by this novel MGO adsorbent were 9.09 mg/g. Desorbing agents NaOH was used for desorption process. Nearly, 17.1% efficiency was reduced even after 5 cycles of adsorption-desorption and proved can be reuse. This novel MGO adsorbent had been easily separated after the adsorption process. From the study, it is concluded that this neoteric MGO adsorbent a promising, super-eminent candidate for waste water treatment.