Adsorption of n-Heptane and 2-Methylheptane in the Gas Phase on Polyvinylidene Chloride-Based Microporous Activated Carbon

• Published in: Energy & fuels 2007-09, Vol.21 (5), p.2929-2934
• Main Authors: Jiménez-Cruz, Federico, Hernández, J. A, Laredo, Georgina C, Mares-Gallardo, Maria Teresa, García-Gutierrez, José Luis
• Format: Article
• Language: English
• Subjects: Chemistry; Exact sciences and technology; General and physical chemistry; Ion-exchange; Surface physical chemistry; Zeolites: preparations and properties
• ISSN: 0887-0624; 1520-5029
• DOI: 10.1021/ef070072c

The selective adsorption of n-heptane and 2-methylheptane was tested on polyvinylidene chloride-based microporous carbon (CMS-IMP12) prepared from pyrolysis of poly(vinylidene chloride-co-vinyl chloride) (PVDC-PVC) copolymer. CMS-IMP12 was characterized by textural analysis, scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), and Fourier transform infrared (FTIR) and Raman spectroscopies. These results indicate the presence of graphene subunits inside the amorphous carbon and great quantity of sp2 carbon type in CMS-IMP12. It was found that 2-methylheptane is better adsorbed than n-heptane on the carbon sample by an inverse gas chromatography (IGC) adsorption study at 275−350 °C. Structural features of the carbonaceous material, entropy restrictions by steric parameters, diffusion conditions, and cooperative CH/π interactions between CH in n-heptane and 2-methylheptane and π electrons in the carbon walls determine the selective adsorption.