Efficiently activated carbons from corn cob for methylene blue adsorption

In this study, activated carbon was prepared from an abundant Egyptian agricultural waste material (Corn Cob) through microwaves assisted activation. The effect of using two different activating agents (potassium hydroxide and ammonium sulfate), with various ratios of impregnation (RI) (0.25, 0.75, and 1.25), on the adsorption capacities were investigated. The prepared activated carbon was characterized using Raman spectroscopy, scanning electron microscopy (SEM), and nitrogen adsorption–desorption. The efficiency of the prepared activated carbon as an adsorbent was investigated by studying the removal of methylene blue (MB) as organic pollutants from aqueous solutions. Adsorption experiments for the prepared activated carbon are described in detail. The parameters affecting the adsorption process such as contact time, initial dye concentration were discussed in detail as well. The adsorption isotherm process fits well with the Langmuir model and the maximum adsorption capacity was qmax = 333 mg/g. The adsorption kinetics data fitted well with the pseudo-second-order model. Accordingly, the prepared activated carbon can be utilized for the remediation of wastewater from organic pollutants with high efficiency and superior stability.