Sustainable mitigation strategy of sulphate and phosphate ions from binary mixture using Fe-Co@rGO nanocomposite: kinetics, isotherm and thermodynamic studies
摘要
Water pollution is severely affecting the water bodies with different contaminants. Sulfur (as sulphate ions) and phosphorous (as phosphate ions) are essential ingredients that are usually used in industries i.e. paper making, fertilizer, food processing and detergent, which causes substantial water pollution. To eliminate these anions a graphene based nanoadsorbent (Fe-Co@rGO) was synthesized by using aqueous extract of Ricinus communis plant. To confirm the synthesis and functional groups involved in production of nanoadsorbent, UV–visible spectroscopy and FTIR was performed. Morphology was depicted as embedded nanoparticles on graphene sheets were confirmed by SEM images. To calculate the size of Fe-Co@rGO i.e. 11.18 nm, XRD was performed. EDX corresponds to the elemental composition of synthesized nanoadsorbent. BET surface area analysis confirmed about the specific surface area and porosity of the synthesized Fe-Co@rGO nanocomposite. During adsorption of anions on catalytic surface of nanoadsorbent various factors (initial ion concentration, adsorbent dosage, pH factor, temperature and time) were optimized under tungsten lamp and without aid of tungsten lamp. 10 mg of adsorbent dose removed 95% of phosphate and 97% of sulphate under tungsten lamp from binary mixture of ions in contact time of 20 min with adsorbent. Spontaneous and endothermic nature of reaction was revealed by thermodynamic parameters. Pseudo 2nd order was the best fitted model due to R2 value near to unity. Freundlich isotherm was best fitted model. From regeneration study efficiency of nanoadsorbent was evaluated with 2 to 4% loss of catalytic efficiency.