Loughborough University
Leicestershire, UK
LE11 3TU
+44 (0)1509 263171
Loughborough University

Loughborough University Institutional Repository

Please use this identifier to cite or link to this item: https://dspace.lboro.ac.uk/2134/20031

Title: Pore size distributions derived from adsorption isotherms, immersion calorimetry, and isosteric heats: a comparative study
Authors: Madani, S. Hadi
Hu, Cheng
Silvestre-Albero, Ana
Biggs, Mark J.
Rodríguez-Reinoso, Francisco
Pendleton, Phillip
Issue Date: 1-Jan-2016
Publisher: © Elsevier
Citation: MADANI, S.H. ...et al., 2016. Pore size distributions derived from adsorption isotherms, immersion calorimetry, and isosteric heats: A comparative study. Carbon, 96, pp. 1106-1113.
Abstract: We compare the pore size distribution of a well-characterized activated carbon derived from model-dependent, adsorption integral equation (AIE) methods with those from model-independent, immersion calorimetry and isosteric heat analyses. The AIE approach applied to nitrogen gave a mean pore width of 0.57 nm; the CO2 distribution exhibited wider dispersion. Spherical model application to CO2 and diffusion limitations for nitrogen and argon were proposed as primary reasons for inconsistency. Immersion enthalpy revealed a sharp decrease in available area equivalent to a cut-off due to molecular exclusion when the accessible surface was assessed against probe kinetic diameter. Mean pore width was identified as 0.58 ± 0.02 nm, endorsing the underlying assumptions for the nitrogen-based AIE approach. A comparison of the zero-coverage isosteric heat of adsorption for various non-polar adsorptives by the porous test sample was compared with the same adsorptives in contact with a non-porous reference adsorbent, leading to an energy ratio or adsorption enhancement factor. A linear relationship between the energy ratio and probe kinetic diameter indicated a primary pore size at 0.59 nm. The advantage of this enthalpy, model-independent methods over AIE were due to no assumptions regarding probe molecular shape, and no assumptions for pore shape and/or connectivity.
Description: this paper is in closed access.
Sponsor: This paper was funded by the Australian Research Council discovery program (DP110101293).
Version: Published
DOI: 10.1016/j.carbon.2015.10.072
URI: https://dspace.lboro.ac.uk/2134/20031
Publisher Link: http://dx.doi.org/10.1016/j.carbon.2015.10.072
ISSN: 0008-6223
Appears in Collections:Closed Access (Chemistry)

Files associated with this item:

File Description SizeFormat
As published.pdfPublished version886.28 kBAdobe PDFView/Open

 

SFX Query

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.