Characterization of the PSD of activated carbons from peach stones for separation of combustion gas mixtures

• Published in: Adsorption : journal of the International Adsorption Society 2011-10, Vol.17 (5), p.853-861
• Main Authors: Soares Maia, Débora A., de Oliveira, J. C. Alexandre, Toso, Juan Pablo, Sapag, Karim, López, Raul H., Azevedo, Diana C. S., Cavalcante, Célio L., Zgrablich, Giorgio
• Format: Article
• Language: English
• Subjects: Chemistry; Chemistry and Materials Science; Engineering Thermodynamics; Heat and Mass Transfer; Industrial Chemistry/Chemical Engineering; Surfaces and Interfaces; Thin Films
• ISSN: 0929-5607; 1572-8757
• DOI: 10.1007/s10450-011-9344-4

Controlled series of microporous carbons were prepared through chemical activation with phosphoric acid from peach stones as the precursor material, corresponding to different preparation conditions. Adsorption isotherms of N 2 at 77 K and of CO 2 at 273 K were measured to be used in the characterization of the samples. The recently proposed mixed-geometry model (MGM), which assumes that the activated carbon is better represented by a mixture of slit and triangular geometry pores, is used to obtain the PSDs of the samples, on the basis of Grand Canonical Monte Carlo (GCMC) simulated ideal isotherms, both for N 2 at 77 K and of CO 2 at 273 K. Our results emerging from the analysis of two families of activated carbons reveal a consistent picture supporting the thesis that the PSDs of the same sample obtained trough N 2 and CO 2 adsorption are different, a still controversial issue in the literature. Comparison of predictions from the MGM with those of the pure slit geometry model (PSGM) shows that the former gives a more consistent picture and more similar PSDs for the two adsorbates used.