Green synthesis of Iron nanoparticle from the extract of waste cauliflower leaves: An application for the removal of an anionic dye (Methyl Orange)

In this study, we have synthesized iron nanoparticles with the help of an environmentally benign technique using the extract of waste cauliflower leaves (Ca-INPs). This method of green synthesis of nanoparticles reduces the hazardous impact chemical synthesis method as well as it also allows the use of biological waste for the synthesis that ultimately reduces the production cost. Synthesized were used for the adsorptive removal of an anionic dye Methyl Orange (MO) from its aqueous solution after characterizing them with scanning electron microscope (SEM) and energy dispersive spectroscopy (EDS). The adsorption process was optimized by varying different parameters that were Ca-INPs concentration, initial MO concentration, contact time and pH. Maximum adsorption of MO was found at 2 g/L concentration of MO with initial MO concentration 5 mg/L. equilibrium time for adsorption was observed to be 120 min. the adsorption process was also analyzed by the application of Langmuir and Freundlich isotherm and pseudo-first-order and pseudo-second-order kinetic to understand the mechanism behind the adsorption of MO onto Ca-INPs. The adsorption process was best followed by Freundlich isotherm and pseudo-second-order kinetic reaction. Maximum adsorption capacity of Ca-INPs for MO adsorption was found to be 21.73 mg/g.