Removal of Acid Red G dye from aqueous solutions by adsorption to MCM-41-layered double hydroxides composite

Abstract

MCM-41 supported layered double hydroxides (LDH) composite materials (ML) were synthesized and studied for removal of Acid Red G (ARG), an anionic dye, with the adsorption method. ML was prepared using in situ synthesis procedure for the low supersaturation coprecipitation method, and ML10 and ML20 presented promising application towards ARG dye adsorption capacity in industrial wastewater. Powder samples were characterized by Xray diffraction, FTIR spectroscopy, scanning electron microscopy and energy dispersive spectrometry. The effects of different reaction time, initial solution pH and temperature on the dye adsorption capacity were investigated. Adsorption process was well described by pseudo-second-order kinetic model and Langmuir isotherm model. The fitting curves showed that ML10 and ML20 had higher adsorption rates and maintained a certain theoretical saturated adsorption capacity (92.19807mg/g and 96.41947mg/g, respectively) compared with LDH.