Eco-Friendly Application of Mauritanian Limestone Clay: Malachite Green Removal from Textiles Wastewater Case Study

The present work has been performed to evaluate the employability of natural limestone clay in the removal of Malachite Green (MG) from aqueous solution. Some parameters such as adsorbent dosage, pH, contact time, temperature, and initial concentration on the removal rate were studied. Adsorption kinetic data were analyzed using Pseudo First Order (PFO) and Pseudo Second Order (PSO) models. For the kinetic study, the adsorption process was fitted to the PSO model. The Langmuir, Freundlich, and Sips isotherms were applied to fitting the experiment data. The results indicate that the parameters of the isotherm models are appropriate to fit the current adsorption isotherm data in the following order: Langmuir > Sips > Freundlich. The maximum uptake amount qm, was found to be 55.84 mg g−1. The present work shows that the clay is a promising adsorbent for the removal of MG from aqueous solutions.