An investigation into equilibrium, Kinetics, and thermodynamics of yellow bemacid dye removal from Aqueous Solutions using pomegranate skin (PG) and Date Pedicels (DPd) as Green Adsorbents

Abstract

There has been substantial research focused on developing environmentally friendly materials to remove pollutants from wastewater. In this regard, a key study area is focused on green materials derived from plants and agricultural wastes. These materials have shown promising results in removing pollutants from water, providing a sustainable solution for wastewater treatment. Additionally, using plant-based materials has helped reduce reliance on traditional chemical-based methods, contributing to a more environmentally friendly approach. The current study investigated the efficacy of utilizing pomegranate skin (PG) and date pedicels (DPd) as potential green adsorbents for the elimination of synthetic dye Yellow Bemacid (YB) from aqueous solutions. The investigation involved adsorption tests conducted under various experimental conditions, such as contact time, solution pH, initial dye concentration, and temperature. The obtained findings manifested that both PG and PdD exhibited considerable adsorption capacities for YB, quantified at 20.75 mg/g and 12 mg/g, respectively. The Langmuir model exceptionally fit the experimental data, and the adsorption kinetics closely followed the pseudo-second-order model for both materials studied. The thermodynamic parameters unveiled that the adsorption of YB was a feasible, spontaneous, and endothermic process, with enthalpy (ΔH) values of 2.330 and 4.165 kJ/mol for PG and PdD, respectively. Furthermore, the favourable affinity between the materials PG, PdD, and the YB molecules was indicated by the positive values (0.010 and 0.014 kJ/mol.K ) of entropy (∆S⁰). Lastly, the negative values of the free enthalpies (∆G⁰ < 0) for the studied systems signified the spontaneity of the adsorption process.