ABSTRACT
An exceedingly facile green approach that produces a reliable adsorbent based on a transition metal such as Iron (Fe) using Mangifera indica leaf extract at room temperature is described. A single pot method was used for synthesis with no capping agents, surfactants or other templates. The main intention of this study is to synthesize iron nanoparticles from leaf extract (Mangifera indica) and examine its degradation potential for photo-catalytic removal of dyes (Congo red and brilliant green) from wastewater. Characterization of synthesized nanoparticles was executed by pHpzc, scanning electron microscopy and Fourier transform infrared spectroscopy studies and results confirm the presence of iron nano-sheets with biomolecules. All photo-catalytic experimental results were assessed by sum of squared estimate of errors and simple linear regression R2 with dye concentration, pH, contact time and dose rate as dependent and independent variables. Adsorption experimental data was verified by kinetics and isothermal models. Results showed that Langmuir and pseudo second order models give best fitness towards the photo-catalytic adsorption procedure. Thermodynamics revealed that adsorption mechanism is endothermic, described by the values of changes in Gibbs free energy, enthalpy and entropy, and is chemisorption in nature, with spontaneous processes. Overall photo-catalytic adsorption execution with synthesized iron nanoparticles and simple biomass of Mangifera indica gives satisfactory results for treating dye wastewater.
