(545b) Optimization and Green Synthesis (Delonix regia mediated) of Zero Valent Iron Nanoparticles

The present study focused to investigate the green synthesis of zero valent iron nanoparticles (ZVI-NPs) from D. regia. In order to produce maximum conversion (%) of Fe³⁺ to ZVI-NPs and minimum hydrodynamic size of ZVI-NPs, one variable at a time (OVAT) and response surface methodology (RSM) were adopted for process optimization. Confirmation of biosynthesis of ZVI-NPs was primarily done using UV-Visible spectrophotometer. The crystalline phase of nanoparticles was detected using X-ray diffraction (XRD) analysis, morphology and particles size of ZVI-NPs were analyzed by transmission electron microscopy (TEM) and scanning electron microscopy (SEM) images were recorded further for analyzing surface topography using field emission gun-scanning electron microscopy (FEG-SEM). Based on outputs of OVAT and RSM, maximum conversion (%) and hydrodynamic size of colloidal ZVI-NPs was experimentally confirmed using ICP-MS and DLS analysis. Results showed that out of the five parameters tested (reaction time, salt concentration, volume ratio of leaf extract to salt, pH and temperature), factors like reaction time, salt concentration, volume ratio of leaf extract to salt (Fig. 1) contributed significantly except pH and temperature. The maximum conversion (%) obtained 31% by OVAT and 72% by RSM. Hydrodynamic size obtained 72 nm by OVAT to 40 nm by RSM. Further, ANOVA for interaction of parameters and its coefficients is studied for the conversion (%) and hydrodynamic size of ZVI-NPs. The adequacy of fitted model was checked by F-test.

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