Palm Kernel Shell and Coconut Shell were utilized for the preparation of activated Carbon (AC) by microwave assisted NaCl/CaCl2 chemical activation at microwave radiation power of 700W and radiation time of 20 minutes. The activated carbon Samples were characterized by, Scanning Electron Microscopy (SEM) coupled with Energy Dispersive X-,Ray Spectroscopy, X- Ray Diffraction (XRD), moisture content, ash content and adsorption study.
The moisture content in all the samples fall within the acceptable range of less than 70%, according to Tierney et al.,2006, which indicates that the adsorption of moisture by the samples is also less. Among the activated carbon samples, sample E has the least moisture content of 6.50 % and an ash content of 3.66%, which suggests that sample E is very viable for adsorption.
The adsorptive properties of the AC samples were quantified using methylene blue (MB), as a model adsorbate. Results showed that the adsorption capacities of the AC samples for MB fitted well in the Langmuir model of adsorption with a maximum adsorption capacity of 333.3mg/g.The adsorption capacity was influenced by theporosity of activated carbon of which the development of the porosity of activated carbon was affected by the Microwave power and the presence of activating agents for impregnation.
In SEM, Sample E gives a clearer pore structure, having more volume of pores and better pore structures with little agglomeration, making it more viable for adsorption in comparison with the other prepared samples.
In XRD characterization, the presence of irregular patterns of X-Ray diffractograms may be accounted for amorphous state of the samples. A sharp peak, which corresponds to CaCl2, was observed at 26.5° and also, sharp peaks corresponding to NaCl, were observed at two theta 31.5° and 45.0° in Sample E.The findings revealed the potential use of a blend of Palm Kernel and Coconut Shells derived activated carbon for dyes removal and/or impurities within the size range of 1.5nm from wastewater, in general and for the removal of MB, in particular.