Nonlinear Fitting for Estimation of Adsorption Equilibrium, Kinetic and Thermodynamic Parameters of Methylene Blue onto Activated Carbon

Authors : Ibrahim Yaagoub ERWA, Omer ISHAG, Omar ALREFAEİ, Issa HASSAN

Pages : 67-84

Doi:10.18596/jotcsa.904311

View : 11 | Download : 5

Publication Date : 2022-02-28

Article Type : Research Paper

Abstract :Adsorption equilibrium, kinetics, and thermodynamics of methylene blue dye insert ignore into journalissuearticles values(MB); from aqueous solutions onto activated carbon insert ignore into journalissuearticles values(AC); synthesized from pomegranate peel was conducted in controlled batch systems. The effects of initial MB concentration, AC particle size, contact time, and temperature on adsorption were evaluated. Under the optimized conditions insert ignore into journalissuearticles values(i.e., contact time 120 min, pH ∼ 5, particle size 125 µm, dye concentration 20 mg/L, temperature 333 K, and 0.5 g AC/50 mL MB solution);, the removal percentages can achieve ∼ 98.28%. The nonlinear method was conducted for estimating the equilibrium and kinetic parameters, where the equilibrium data were fitted to the Langmuir isotherm model. The Langmuir isotherm suggested a maximum monolayer adsorption capacity of 5.03 mg/g at 60 °C. The pseudo-second-order kinetic model provided the best fit to the experimental data compared with the pseudo-first-order. Kinetic studies showed that the adsorption equilibrium was rapidly established, with low activation energy entailed for adsorption insert ignore into journalissuearticles values(Ea; 15.60 kJ/mol);. Thermodynamic parameters showed that the adsorption was spontaneous insert ignore into journalissuearticles values(−∆G° and +∆S°);, exothermic insert ignore into journalissuearticles values(+∆H°);, and favorable at ambient conditions.
Keywords : Methylene blue, Adsorption isotherms, Kinetics, Thermodynamic parameters, Nonlinear fitting