, Volume 17, Issue 2, pp 293–301 | Cite as

Effects of active carbon pore size distributions on adsorption of toxic organic compounds

  • Peter BrantonEmail author
  • Robert H. Bradley
Open Access


The use of active carbons for the removal of toxic organic compounds, for example from air or smoke, is of significant interest. In this paper, the equilibrium and dynamic adsorption characteristics of two active carbons are explored; one microporous coconut based and the other micro-mesoporous derived from a synthetic resin. Benzene, acetaldehyde and acrylonitrile were chosen as the probe toxicant vapours and adsorption was measured at a temperature of 298 K. The nitrogen equilibrium data (at 77 K), analysed using the BET, Dubinin-Radushkevich equations and DFT models, showed a higher overall adsorption capacity, more supermicroporosity and a higher proportion of pores wider than 2 nm for the synthetic resin based material. A micropore distribution biased toward the ultramicropore width-range was observed for the nutshell material. As a consequence, the characteristic adsorption energies in micropores are higher for the nutshell material than the resin based carbon. The effect of these different pore size characteristics on the adsorption kinetics, obtained by fitting the data to the linear driving force (LDF) model, is that the resulting adsorption rate constants are higher across much of the relative pressure range (p/p s ) studied for the resin based carbon compared to the nutshell material. Significantly, the wider pores of the resin-based carbon result in higher rates of adsorption in the micropore filling domain. When evaluated under dynamic conditions in cigarette smoke, improved toxicant removal was observed using the resin based carbon.


Active carbon Adsorption Pore size distribution Smoke Toxic organic compounds 


  1. Adamson, A.W.: Physical Chemistry of Surfaces, p. 609, 5th edn. Wiley, New York (1990) Google Scholar
  2. Bansal, R.C., Goyal, M.: Activated Carbon Adsorption. CRC Press, Boca Raton (2005) CrossRefGoogle Scholar
  3. Bradley, R.H.: The adsorption of vapours by activated and heat-treated microporous carbons, part 1: characterisation of pore structure using the Dubinin-Polanyi approach. Carbon 29, 893–897 (1991) CrossRefGoogle Scholar
  4. Branton, P.J., et al.: The effect of carbon pore structure on the adsorption of cigarette smoke vapour phase compounds. Carbon 47, 1005–1011 (2009) CrossRefGoogle Scholar
  5. Brunauer, S., et al.: Adsorption of gases in multimolecular layers. J. Am. Chem. Soc. 60, 309–319 (1938) CrossRefGoogle Scholar
  6. Dubinin, M.M.: Fundamentals of the theory of adsorption in micropores of carbon adsorbents: characteristics of their adsorption properties and microporous structures. Carbon 27, 457–467 (1989) CrossRefGoogle Scholar
  7. Dubinin, M., Astakhov, V.A.: Development of the concepts of volume filling of micropores in the adsorption of gases and vapours by microporous adsorbents. Adv. Chem. Ser. 102, 69 (1971) CrossRefGoogle Scholar
  8. Dubinin, M.M., Radushkevich, L.V.: Equation of the characteristic curve of activated charcoal. Proc. Acad. Sci. USSR 55, 331 (1947) Google Scholar
  9. Dubinin, M.M., Timofeyev, P.: Adsorption of vapours on active carbons in relation to the properties of the adsorbate. Dokl. Akad. Nauk SSSR 54, 701–704 (1946) Google Scholar
  10. Dubinin, M.M., et al.: Integrated study of the porous structure of active carbons from carbonized sucrose. Carbon 2, 261 (1964) CrossRefGoogle Scholar
  11. Fletcher, A.J., et al.: Role of surface functional groups in the adsorption kinetics of water vapour on microporous carbons. J. Phys. Chem. C 111, 8349–8359 (2007) CrossRefGoogle Scholar
  12. Gregg, S.J., Sing, K.S.W.: Adsorption, Surface Area and Porosity, 2nd edn., p. 41. Academic Press, London (1982) Google Scholar
  13. Jagiello, J., et al.: Using DFT analysis of adsorption data of multiple gases including H2 for the comprehensive characterisation of microporous carbons. Carbon 45, 1066–1071 (2007) CrossRefGoogle Scholar
  14. Marsh, H., Rand, B.: In: Proc. 3rd Conf. on Carbon and Graphite, p. 172. SCI, London (1970) Google Scholar
  15. Mola, M., et al.: The characterisation and evaluation of activated carbon in a cigarette filter. Adsorption 14, 335–341 (2008) CrossRefGoogle Scholar
  16. Rao, M.B., et al.: Mathematical modeling of diffusive potentials within carbon molecular sieves. In: Amer. Carbon Soc., Ext Abs. 17th Biennial Carbon Conf., Lexington, Kentucky, p. 114 (1985) Google Scholar
  17. Reid, C.R., Thomas, K.M.: Adsorption kinetics and size exclusion properties of probe molecules for the selective porosity in a carbon molecular sieve used for air separation. J. Phys. Chem. B 105, 10619–10629 (2001) CrossRefGoogle Scholar
  18. Rutherford, S.W., Coons, J.E.: Equilibrium and kinetics of water adsorption in active carbon molecular sieve: theory and experiment. Langmuir 20, 8681–8687 (2004) CrossRefGoogle Scholar
  19. Stoecki, F.: Recent developments in Dubinin’s theory. Carbon 36, 363 (1997) CrossRefGoogle Scholar
  20. Stoeckli, F.: Dubinins theory and its contribution to adsorption science. Russ. Chem. Bull. 12, 2265–2272 (2001) CrossRefGoogle Scholar
  21. Stoeckli, F., et al.: The comparison of experimental and calculated pore size distributions of activated carbons. Carbon 40, 383–388 (2002) CrossRefGoogle Scholar
  22. Sugden, S.J.: The determination of surface tension from the maximum pressure in bubbles, part II. J. Chem. Soc., Trans. 125, 27 (1924) CrossRefGoogle Scholar
  23. Thomsen, H.V.: International reference method for the smoking of cigarettes. Recent Adv. Tob. Sci. 18, 69–94 (1992) Google Scholar
  24. Toda, Y., et al.: Fine structure of carbonized coals. Carbon 8, 565 (1970) CrossRefGoogle Scholar

Copyright information

© The Author(s) 2010

Authors and Affiliations

  1. 1.Group Research and DevelopmentBritish American TobaccoSouthamptonUK
  2. 2.Carbon TechnologyMatSIRC Ltd.CumbriaUK

Personalised recommendations