Studying chemical activation in carbon xerogels
Chemical activation of carbon xerogels synthesized with different resorcinol/sodium carbonate molar ratios (R/C) was performed using alkaline hydroxides (KOH and NaOH). The effect of R/C and the type and amount of alkaline hydroxide on the final properties of the activated carbon xerogels were evaluated. It was found that, in general, both hydroxides produce an increase in microporosity regardless of the R/C value chosen, without altering the meso/macroporosity developed during the synthesis. KOH develops the microporosity of micro-mesoporous carbon xerogels more efficiently than NaOH, and for samples of large pore size (micro-macroporous samples), a similar textural development was observed for both hydroxides. However, when NaOH is used as activating agent, it is more difficult to eliminate residual Na from the activated carbon xerogels.
KeywordsCarbon Xerogels Carbon Dioxide Adsorption Macropore Size Narrow Micropore Alkaline Hydroxide
L.Z. acknowledges the financial support received from the CSIC I3P Programme and cofinanced by the European Social Fund, for a PhD thesis grant and for a 5-month stay in the Laboratoire de Génie Chimique of the University of Liège (Belgium). N.J. is grateful to the F.R.S.-FNRS (Belgium) for a postdoctoral fellowship. The Belgian authors thank the Fonds de Recherche Fondamentale Collective, the Ministère de la Région Wallonne and the Interuniversity Attraction Pole (IAP/P6-17) for the financial support received and acknowledge the involvement of their laboratory in the Network of Excellence FAME of the European Union Sixth Framework Programme.
- 15.Dubinin MM (1975) In: Danielli JF, Rosenberg MD, Cadenhead D (eds) Progress in surface and membrane science. Academic Press, New YorkGoogle Scholar
- 17.Duong DD (1998) Adsorption analysis: equilibria and kinetics. Imperial College Press, LondonGoogle Scholar
- 19.Bragg WH (1918) In: Bragg WH, Bragg WL (eds) X-rays and crystal structure. Bell and Song, LondonGoogle Scholar
- 21.Cuesta A (1994) PhD thesis, INCAR-CSIC, Oviedo, SpainGoogle Scholar