Nanodimensional AlMCM-41 material for adsorption of dyes: Thermodynamic and kinetic studies

AlMCM-41 was applied for adsorption of methylene blue (MB) and auramine (AU) in single and binary component systems. In the single component systems, AlMCM-41 represents higher adsorption capacity for MB than AU with the maximal adsorption capacity of 2.07×10−4 and 1.15×10−4 mol/g at 25 ˚C for MB and AU, respectively. In the binary component system, MB and AU exhibit competitive adsorption onto the adsorbent. In single and binary component systems, kinetic and adsorption isotherm studies demonstrate that the data are following pseudo-second-order kinetic model and Langmuir isotherm. Also, in both cases, kinetic data is fairly described by two-step diffusion model.  Effect of solution pH on the adsorption of MB and AU in single and binary component systems was studied and the results were described by electrostatic interactions.