Kinetic and thermodynamic approaches on Rhodamine B adsorption onto pomegranate peel

Abstract

In the present study, the adsorption potential of pomegranate peel for the removal of Rhodamine B (RhB) was investigated in a batch system. Kinetic and thermodynamic studies of adsorption were conducted. The rate adsorption of RhB was rapid, attained equilibrium at about 120 ​min, at which the adsorption capacity is close to 30,47 ​mg/g, and this in the initial dye concentration of 100 ​mg/L. The kinetic modeling of RhB adsorption was investigated using four celebrated models: pseudo-first order, pseudo-second order, Elovich, and intraparticle diffusion. According to the values of R2, RMSE, ARE, and χ2 it was found that the pseudo-second order model provided a better fit to kinetic data. The results also show that intraparticle diffusion is not the only rate-limiting step on RhB adsorption onto pomegranate peel. Moreover, the thermodynamic study revealed no-spontaneous and endothermic nature of the adsorption process.

Keywords

• Adsorption
• Kinetic
• Pomegranate peel
• Rhodamine B
• Thermodynamic