Novel adsorbent based on Argan Spinosa leaves modified with citric acid for effective removal of crystal violet dye from textile effluents

Abstract

Over the recent decades, water contamination has surged, emerging as a critical global concern. This study focuses on the removal of crystal violet (CV) dye from water, employing citric acid-modified Argan Spinosa leaves (CA@Arg-Sp) as effective adsorbent. The newly functionalized adsorbent were examined using SEM, FTIR and TGA/DTA. In addition, thermal stability tests demonstrated that the CA@Arg-Sp material maintains structural integrity up to 260 °C. The study tested the efficacy of CA@Arg-Sp in removing CV dye from wastewater up to 99.5 % at pH 7. Electrostatic attractions and hydrogen bonding were identified as crucial factors enhancing CV adsorption. Adsorption performance was further analyzed concerning adsorbent dosage, initial dye concentration, temperature, contact time, and pH. Freundlich isotherm and pseudo-second-order models provided excellent fits for both isotherm and kinetic adsorption simulations. CA@Arg-Sp demonstrated a maximum adsorption capacity of 335.09 mg g−1. Thermodynamic investigations confirmed the endothermic and spontaneous character of the CV elimination mechanism. In general, CA@Arg-Sp is a low-cost, regenerative, and eco-friendly adsorbent for textiles effluents treatment.