Valorization of Sepia Bone as a Bio-Sourced Adsorbent via Simple Modification for Removal of Methylene Blue

The aim of this work is to valorize co-products from the shellfish processing industry in the Souss Massa region (Morocco) for the depollution of dye-laden water. We developed an adsorbent material based on the thermal modification of sepia bone, and studied its effectiveness in removing a cationic dye methylene blue (MB) using the batch adsorption method. In this context, we have used a large wide of characterization techniques (SEM-EDX, XRD, FT-IR, TGA and pH_PZC) for morphological, composition, crystallinity and surface charge. Removal of MB dye by this adsorbent was carried out and the effects of physicochemical factors such as initial pollutant concentration, adsorbent dose, contact time, pH and temperature were investigated. The pseudo second order could be best describe the adsorption kinetic (R² = 0.99). The Adsorption mechanism of MB on the calcined sepia bone agree well with Langmuir model (q_{max, cal} =81.37 mg/g). The calculated thermodynamic suggest the adsorption on the biomaterial is spontaneous and exothermic. The results of Taguchi experimental design and analysis of variance showed that contact time, adsorbent mass and initial concentration are the most important factors affecting the removal efficiency with a contribution of 48.33%, 27.86%, and 9.09%, respectively. The prepared biomaterial was easily regenerated using Calcination methods, with a slight variation in adsorption capacity up to seven cycles.