56-LQP-JABS 20260903105623 Lumina Quest Publishing m.arslansohail@gmail.com Lumina Quest Publishing Journal of Advanced Biological Sciences J. Adv. Biol. Sci. 3134-8823 10.66590/jabs https://lquestpub.com/archives.php?journal=journal-of-advanced-biological-sciences 12 30 2026 12 30 2026 1 2 10.66590/jabs20240102 https://lquestpub.com/articles-list.php?journal=journal-of-advanced-biological-sciences&volume=1&issue=2 Adsorption of Sunset Yellow (E110) Food Dye onto Granular Activated Carbon: Thermodynamic and Kinetic Evaluation Ibrahim Younus Mohammed Abeer Qais Younes Abddahah Khaleel Ibrahim This study investigated the adsorption behavior of the artificial food dye Sunset Yellow (E110) using granular activated carbon as an adsorbent material. Sunset Yellow is a complex, high-molecular weight chemical compound containing several active functional groups. The adsorption characteristics of the dye were evaluated through spectrophotometric analysis using UV-Visible spectroscopy to establish a standard calibration curve and determine the remaining dye concentration after adsorption. Adsorption capacity and removal efficiency were subsequently calculated. Several factors affecting the adsorption process were examined, including the initial dye concentration, temperature range (298-318 K), adsorbent dosage, contact time and solvent type. Thermodynamic parameters of the adsorption process were determined using equilibrium constant values and the Van’t Hoff equation. The calculated positive values of enthalpy change (ΔH°) and distribution coefficient (Kd) indicated that the adsorption process was endothermic in nature. Since the ΔH° values did not exceed 40 kJ/mol, the adsorption was identified as predominantly physical adsorption. The negative Gibbs free energy (ΔG°) values obtained from equilibrium constant calculations demonstrated that the adsorption process was spontaneous at lower temperatures, with spontaneity increasing as temperature increased while maintaining a constant initial dye concentration. However, increasing the initial dye concentration at constant temperature reduced the spontaneity of adsorption. In contrast, calculations based on Kd values produced positive ΔG° values, indicating non-spontaneous adsorption behavior under those conditions. Positive entropy values (ΔS and ΔS°) suggested increased molecular organization of dye molecules at equilibrium during the adsorption process. The sticking probability (S*) was calculated using the modified Arrhenius equation and the obtained values fell within the preferred adsorption range (0<S*<1), confirming the predominance of physical adsorption on the adsorbent surface. Furthermore, the apparent activation energy values indicated that the adsorption process was diffusion-controlled and favored lower temperatures within the experimental range investigated in this study. 12 30 2026 12 30 2026 7 14 10.66590/jabs2024010202 https://lquestpub.com/article/10.66590/jabs2024010202