Chemical and Biological Synthesis of Fe3O4 Nanoparticle and its Application for Removal of Methylene Blue from Aqueous Solution

Abstract

The application of greenly and chemically synthesized iron oxide (magnetite) nano particles for the removal of methylene blue from an aqueous solution is what was studied in this thesis. The XRD, FT-IR, UV-Visible spectroscopy and SEM results reveal that a chemical and greenly synthesized iron nano particle with a different size was synthesized using Prosopis Juliflora leaf extract and ferric and ferrous chloride salt precursors. The average crystal ssize of the synthesized NPs was calculated using the Debye-Scherer equation. The average crystal size of magnetite NPs was found 16nm (1:1 ratio), 19nm (1:2 ratio), 14nm (2:1 ratio) and 12nm( chemical mwthod). FTIR spectrum of magnetite NPs showed the intraction between the functional groups and phytochemical in the Prosopis julifera leaves extract and magnetite NPs. The deployment of greenly synthesized iron oxide nanoparticle (GInP) in the removal of methylene blue was studied after this diminutive GInP had been procreated by reduction of ferric iron in presence of P. juliflora leaf extract and coprecipitation for chemical method. The methylene blue dye removal capability of both GInP and chemically synthesized iron oxide nanoparticles was investigated for methylene blue concentrations ranging from 10 ppm - 50 ppm in both methods. Batch adsorption experiments were performed to investigate the influence of pH, contact time, adsorbent dosage, and initial concentration. A maximum methylene blue percentage of 99.75 and 99.505 in the green and chemical methods were observed, respectively at pH 9 for 10 ppm MB concentration in 60 min using 0.5 g of adsorbent dosage. The adsorption kinetics data were well fitted with the pseudo-second-order rate model with high regression coefficient (0.9986 and 0.9973) in the green and chemical method, respectively. The methylene blue removal process was found to be well fitted with the Freundlich isotherm model with determination coefficients valeu of 0.9981 and 0.9836 in the green and chemical methods, respectively. Reusability was also studied by using one sample with 0.5 g for five cycles and up to 84.6% and 83.9% by green and chemical method, respectively of methylene blue can be removed. It has been found that greenly synthesized magnetite nano particle show high selectivity and adsorption capacities for the removal of methylene blue dye from an aqueous solution.