Effects of Physical Activation Procedure on the Production Yield, Surface Chemistry and Surface Pores of Coconut Shells Based Activated Carbons

Abstract

Activated carbons are produced either by physical or chemical activation or both. However, due to different experimental protocols used in preparing and characterising these carbons, it has been difficult in comparing their yields, surface chemistry and pore developments. In this study the effects of physical activation procedure on yields, surface chemistry and surface pore developments of activated carbons prepared by three physical activation procedures using the same protocols were compared. The results of the yields revealed that during the production of activated carbons better yields are obtained when the particle size of the precursor is reduced to the required size of the expected activated carbon prior to carbonisation and activation. The spectra produced by Fourier transmission infrared spectroscopy demonstrated shift in bands and changes in wavelength numbers and absorbance between the raw and the derived activated carbons  during pyrolysis or activation. Comparing the micrographs of the Scanning electron microscope of the derived carbons also showed an irregular and heterogeneous surface morphology with a well-developed porous structure.

Keywords: porosity, micrographs, surface area, yield, activation, spectroscopy