Prediction and interpretation of adsorption parameters for the sequestration of methylene blue dye from aqueous solution using microwave assisted corncob activated carbon

In this study, the waste from the microwave assisted pyrolysis of the corncob process was utilized as an effective adsorbent for the removal of cationic dye (methylene blue) from the aqueous solution. The surface characteristics of microwave assisted corncob (MACC) were investigated by Fourier transform infrared spectrometer (FTIR) and Scanning electron microscopy (SEM) analysis techniques. The influences of several experimental parameters such as initial MB dye concentration, contact time, solution pH, adsorbent dose and temperature were studied to predict the optimum conditions. The adsorption equilibrium data and adsorption rate data were evaluated using the different isotherm and kinetic models. The isotherm results showed that the Freundlich model provides positive results for the studied equilibrium data. The maximum monolayer adsorption capacity of MACC for MB dye was calculated as 82.71 mg g− 1. The adsorption kinetic data best obeyed the pseudo-first order. The thermodynamic parameters, such as ΔG°, ΔH° and ΔS° were also evaluated. The calculated parameters indicated that adsorption process was spontaneous and exothermic in nature. Finally, it can be concluded that the prepared MACC is an economical, environmental friendly, and an effective biosorbent material for the removal of MB dye from water/wastewater.