Valorization of Food Waste as an Eco-Friendly Adsorbent for the Removal of Cationic Textile Dye from Aqueous Solutions: Kinetic, Isotherm and Thermodynamic Studies
Year: 2025
Type: article
Abstract: In this study, Helix aspersa snail shells, a type of food waste and an effective adsorbent, were used to remove methyl violet 2B, a cationic dye commonly found in textile industry wastewater. This adsorbent is cost-effective, environmentally friendly, widely available and highly efficient. The characterization of the material was carried out using several techniques including SEM/EDX, XRD, TGA/DTA and FTIR, to provide a comprehensive analysis of the material’s properties. SEM/EDX analysis showed a heterogeneous morphology of this adsorbent, while XRD confirmed that the main component was CaCO3. After optimizing operational parameters, the highest removal efficiency (93.6%) was achieved at an initial dye concentration of 10 ppm, with particle size less than 0.1 mm, an adsorbent mass of 1.5 g, pH 8, an agitation speed of 700 rpm at a temperature of 20 ºC. The results showed a decrease in removal efficiency with increased ionic strength, with efficiency dropping to 49.5% at NaCl 1 M. The kinetic studies suggested that the adsorption followed a pseudo-second-order model. The adsorption isotherms were best described by the Langmuir model, suggesting monolayer adsorption on a surface with identical sites. Thermodynamic analysis revealed that the phenomenon was exothermic and spontaneous indicating that it is a physisorption process.
Source: Asian Journal of Chemistry
Authors: Sara Meftah, Fatima Zohra Batana, Salima Merghache, Lila Bouzina, Mutlu Sönmez Çelebi
Language: English
Subfield: Water Science and Technology
Field: Environmental Science
Domain: Physical Sciences
Open Access status: diamond
OpenAlex ID: W7107967943