Study of adsorption behavior of methyl orange dye on activated carbon prepared from sugarcane bagasse via chemical activation

Two activated carbon (AC) samples were produced from sugarcane bagasse using different chemical activation substances (H2SO4 and NaOH). The AC sample activated by H2SO4 presented enhanced surface properties compared to the NaOH activated sample, with higher specific surface area and porosity determined by BET and SEM analysis were also tested for methyl orange (MO) adsorption. The adsorption efficiency decreased as MO concentration increased. Experimental data including adsorption isotherms and the Gibbs free energy (ΔG°) thermodynamic potential were analysed. Adsorption experimental results agreed well with the Langmuir adsorption isotherm with a high correlation coefficient (R2) and the chemisorption process formed spontaneously adsorbed monolayers. Therefore, sugarcane bagasse waste was considered as a low cost precursor to prepare AC adsorbents with high pollutant removal efficiency through spontaneously adsorbed monolayers.