One-step synthesis of magnetic fly ash composites for methylene blue removal: batch and column study.

Abstract

This study focuses on the synthesis of magnetic fly ash composites and its application for the removal of methylene blue (MB) from wastewater. By-product of oil power plants, oil fly ash, was treated with magnetic nanoparticles after chemical surface modification and dubbed modified fly ash (MFA). MFA was characterized by X-ray fluorescence, diffractogram analysis, scanning electron microscopy, energy-dispersive X-ray (EDX), and Fourier transform infrared (FT-IR) and N2 physisorption. MB (methylene blue) was removed from an aqueous solution using the response surface modelling (RSM) technique, which was used for optimization reasons. All four independent factors were investigated to see how they affected the removal process: adsorbent dosage; contact time; pH; and beginning dye concentration. The rate of MB removal was strongly influenced by the pH of the solution. The Langmuir and Freundlich models were used to examine equilibrium data A for MB adsorption onto the MFA in linear and nonlinear forms. Langmuir gave a better fit. The adsorption kinetics shown by increased kinetic statistics were better characterized by a pseudo-second-order MFA model. As far as thermodynamic characteristics go, adsorption is endothermic and occurs spontaneously. It has been proven that MFA may be used as an adsorbent to remove MB dye with high efficiency, and the quadratic model has been proved to be statistically significant.