Removal of methylene blue with zinc oxide coated montmorillonite and modeling with fuzzy logic

In this study, clay mineral montmorillonite (MMT) was coated with ZnO to be used as an effective nanocomposite adsorbent. First, the surface properties of the ZnO coated montmorollonite (ZnO/MMT) adsorbent were characterized using Fourier Transform Infrared Spectroscopy, X-Ray Diffraction and Scanning Electron Microscopy. The presence of hexagonal wurtzite ZnO nanoparticles in ZnO/MMT nanocomposites was revealed by X-Ray Diffraction measurements. ZnO/MMT nanocomposite was used as adsorbent to remove methylene blue dye. Then, the effects of different parameters such as contact time, adsorbent dose, initial concentration, temperature and initial pH were investigated. In addition, using these absorbent parameters, a fuzzy model was developed to provide an experimental background for future academic studies and to calculate the removal rates more easily. It showed that the adsorption isotherms obtained from the experimental data and the test data obtained from the fuzzy model are compatible with the Langmiur isotherm model. The highest adsorption capacity was calculated as 384.62 mg/g at 318 K. It was determined that the kinetic model that best describes methylene Blue adsorption is the pseudo-second order kinetic model. Thermodynamic experiments have shown that adsorption is spontaneous and exothermic. Regeneration results show that nanocomposites can be used at least seven times due to their stability and durability. The result is that the ZnO/MMT nanocomposite can serve as a promising adsorbent for the removal of Methylene Blue from aqueous solutions.