Study of the adsorption properties of an almond shell in the elimination of methylene blue in an aquatic

The discharges of many industries are loaded with dyes that pose a major problem for health and the environment. Various techniques and methods (physical, chemical, biological...) were developed for the treatment of the effluents charged in dyes. Adsorption is one of the most suitable techniques for the removal of dyes, and natural wastes are among the most used materials as adsorbents. This work is based on the study of the removal of methylene blue in an aqueous medium, using almond shells as adsorbents. The support used was characterized by X-ray diffraction, Scanning electron microscopy, BET method, and Infrared spectroscopy. The results obtained showed that the adsorption equilibrium is established after 20 minutes. We also evaluated the effect of parameters such as pH effect, mass effect, temperature effect, and particle size effect. The equilibrium adsorption kinetics shows that this support has good retention for methylene blue. The adsorption isotherm obtained is described by the Freundlich model and this adsorption follows a pseudosecond-order equation. The thermodynamic parameters show that the process is endothermic, spontaneous, and disordered.