Kinetics and adsorption isotherms studies for the effective removal of Evans blue dye from an aqueous solution...

In the present day, water treatment has emerged as a significant global concern, particularly due to the proliferation of pollution sources. The utilization of dyes, such as Evans blue, in several industries is among the most significant contributors to these pollutants. Forsterite nanoparticles were synthesized by the sol-gel technique and calcined at different temperatures to determine the optimum temperature at which pure nanoforsterite was obtained. Then, it was analyzed using X-ray diffraction (XRD), atomic force microscope (AFM), transmission electron microscope (TEM), Brunauer-Emmett-Teller (BET) , contact angle, and zero-point charge. The adsorption capability of forsterite nanoparticles (Nps) was evaluated by a batch adsorption experimental method to remove Evans blue dye (EBD). Parameters such as agitation speed, dosage of forsterite Nps, pH, and contact time were considered at ambient temperature. At pH = 3, dose of Nps = 1 g/L, and 600 rpm within 10 min, the results indicated a removal rate of around 100%. Furthermore, it was shown that the material may be employed for 3 cycles with a removal rate of 90%. Multiple kinetic and isotherm models, including Langmuir, Temkin, and Freundlich models, were used to analyze the results and clarify the mechanism of the adsorption phenomena. The findings from the isotherm and kinetic studies indicated that the system conforms to Langmuir and pseudo-second-order, respectively.