Basic Violet 10 (BV10) removal from aqueous solutions using sawdust of<i>Swietenia mahagoni</i>(Mahogany trees): adsorbent characterization, adsorption isotherm, kinetics, and thermodynamic studies

In this work, the adsorption potential of sawdust of Swietenia mahagoni to remove Basic Violet 10 (BV10) from aqueous solutions was investigated by batch adsorption system. The adsorbent was characterized by Fourier transform infrared spectrophotometer, scanning electron microscope, particle size distribution, and Brunauer, Emmett, and Teller methods. The effect of various experimental parameters such as pH, initial dye concentration, adsorbent concentration, and temperature on adsorption of BV10 was investigated. The optimum pH for BV10 adsorption was found to be 4.2. Equilibrium adsorption data were analyzed by the Langmuir, Freundlich, Temkin, and Scatchard isotherm models. The results show that the best fit was achieved with the Langmuir isotherm with a maximum adsorption capacity of 222.76 mg g−1 at 50°C. Pseudo-first-order, pseudo-second-order, intraparticle diffusion, and Elovich models were used to analyze the kinetic data obtained at different BV10 concentrations. The adsorption kinetic data were well described by the pseudo-second-order model. The calculated thermodynamic parameters, namely ∆G°, ∆H°, and ∆S°, showed that adsorption of BV10 was spontaneous and endothermic under examined conditions.