Textural properties of Activated Carbons from Wild Cherry Stones as Determined by Nitrogen and Carbon Dioxide Adsorption

  • Alaya, M.N. (Chemistry Department, Faculty of Science, University of Aleppo) ;
  • Youssef, A.M. (Chemistry Department, Faculty of Science, Mansoura University) ;
  • Karman, M. (Chemistry Department, Faculty of Science, University of Aleppo) ;
  • Abd El-Aal, H.E (Chemistry Department, Faculty of Science, University of Aleppo)
  • Received : 2006.02.01
  • Accepted : 2006.03.10
  • Published : 2006.03.30

Abstract

Activated carbons were obtained by activating wild cherry stones with different concentrations of phosphoric acid or zinc chloride at different temperatures. The adsorption of $N_2$ at 77 K and of $CO_2$ at 273 K was followed and the data were analyzes by considering different adsorption models. The activated carbons obtained measured high surface area with the most of the surface in all samples located in micropores. Fair agreement was found between the nitrogen surface areas calculated from the BET-, t-, ${\alpha}$- and DR- methods, although the first three are based on surface coverage whereas the latter is based on micropore filling. The carbon dioxide surface areas calculated by the DA equation were smaller than the comparable nitrogen areas. This was ascribed to domination of surface coverage mechanism, the absence of activated diffusion process. Based on this explanation the $CO_2$-surface areas as calculated by DA equation should be taken with great reservation.

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