Elimination of Aniline from Aquatic Solution through Activated Carbon Prepared from Phoenix Dactylifera Kinetic and Thermodynamic Studies

This study explores the kinetic and thermodynamic aspects of aniline adsorption on activated carbon produced from result fruit seeds (Phoenix dactylifera). The carbon material (ACPD) was developed using two distinct activation methods: chemical activation with sulfuric acid (ACPD + H2SO4) and physical activation using nitric acid (ACPD + HNO3). Description of the equipped adsorbents was attained via X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), and thermogravimetry analysis (TGA). Adsorption performance was evaluated under various conditions, including changes in dosage of adsorbent, contacting time, solution temperature, pH, and initial adsorbate concentration. The results shown that sulfuric acid activation significantly enhanced aniline removal efficiency, raising it from 12.27% to nearly complete removal (≈100%). Moreover, the chemical activation improved the initial adsorption rate, suggesting a greater affinity and capacity of ACPD + H2SO4 for the aniline uptake. The adsorption procedure was further analyzed through kinetic modeling via pseudo-first-order and pseudo-second-order models. The experimental information aligned extra closely by the pseudo-second-order model of both types of activated carbon, as evidenced by higher correlation coefficients and close agreement with the calculated equilibrium adsorption capacities (qe). Thermodynamic parameters confirmed that aniline adsorption onto ACPD + H2SO4 is a spontaneous and exothermic process, demonstrated by the negative value of ΔG°, ΔH°, and ΔS°. In contrast, adsorption onto ACPD + HNO3 was characterized by positive values of these parameters, indicating an endothermic nature, where higher temperatures favored increased adsorption. The adsorption isotherm results were assessed by Langmuir, Freundlich, and Temkin modeling. The Temkin isotherm had the maximum correlation coefficient (R2 = 0.9675).