Title
Potential of low-cost pomegranate peels adsorbent for dye removal from wastewater: a sustainable solution for agricultural waste valorization
Authors
AMINA BEDOUI, NOUHA SOUDANI, SAMIA BEN ALI, ABDELMOTTALEB OUEDERNI, SOUAD SOUISSI-NAJAR

Received October 14, 2025
Published Volume 60 Issue 3-4 March-April
Keywords Victoria Blue dye, pomegranate peels, wastewater, characterization, biosorption

Abstract
Pomegranate peel (PGP) was valorized as a low-cost and eco-friendly biosorbent for the removal of dyes from wastewater. This study investigates the adsorption performance of unmodified PGP for the removal of Victoria Blue (VB). The biosorbent was characterized using several techniques, including BET analysis, Fourier-transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM). The point of zero charge (pHpzc) and surface acidity/basicity were also evaluated using the pH equilibration method and Boehm titration, respectively. Batch adsorption experiments were conducted to evaluate the effect of key parameters such as initial dye concentration, pH, contact time, and particle size. The optimum removal efficiency was achieved at pH 6, 25 °C, particle size of 0.63 mm, and an equilibrium time of 60 minutes. The adsorption equilibrium data were fitted to the Langmuir, Freundlich, and Temkin isotherm models. Among these, the Langmuir model provided the best fit with a maximum adsorption capacity of 120.48 mg/g. Kinetic studies demonstrated that the adsorption process followed a pseudo-second-order model. Thermodynamic parameters confirmed that the biosorption was spontaneous and exothermic, with negative ΔG° and ΔH° values. These results highlight raw pomegranate peel's potential as an effective and sustainable biosorbent for wastewater treatement.