Chemical Treatment of Moringa Seed Peels for the Efficient Removal of Methylene Blue Macromolecule: Kinetic And Thermodynamic Calculations

Abstract

Moringa seed peels are chemically treated with sulfuric acid to produce a bioadsorbent to remove methylene blue from the aquatic environment. Various techniques are used to examine the properties of the adsorbents such as Fourier transform infrared spectroscopy (FT-IR), Brunauer–Emmett–Teller (BET) surface specification, and scanning electron microscopy (SEM). The adsorption parameters such as adsorbent dose, contact time, initial concentration, temperature, and pH are studied to predict the optimum conditions. The adsorption equilibrium data and adsorption rate data are evaluated using different isotherm and kinetic models. The isotherm results show that the Langmuir model give positive results for the studied equilibrium data. The adsorption kinetic data better follow the pseudo-second-order model. Thermodynamic variables such as ∆S°, ∆H°, and ∆G° are also evaluated. The calculated parameters indicate that the adsorption process is spontaneous and exothermic in nature.