Adsorption of Methylene Blue Onto Acacia Modesta Carbon: Kinetic and Thermodynamic Study

Abstract

The adsorption of methylene blue was carried out by adsorbent prepared from Acacia modesta. The sample wood was collected from Dir lower Khyber Pakhtunkhwa Pakistan. Chemical activation of the sample was conducted for surface efficiency. Surface of raw and activated sample was elucidated by scanning electron microscope (SEM), energy dispersive spectroscopy (EDS) and Fourier transform infrared (FTIR) techniques. Adsorption of methylene blue was studied on raw and activated samples by kinetics adsorption at different adsorption temperatures such as 20 °C, 30 °C and 40 °C. The adsorption equilibrium was established within 2 h. Elovich, Bhangam, and Parabolic diffusion equations were applied to the adsorption kinetics data and were found fit for adsorption. From adsorption kinetic data the parameters like ΔH≠, ΔS≠ and ΔE≠ were calculated and showed that the adsorption process was spontaneous process. Entropy in descending order shows that dye molecules adsorbed in an oriented position.