Characteristic adsorption functions and the surface structure of solid adsorbents

被引:3
作者
László, K
Tóth, J
机构
[1] Univ Miskolc, Res Inst Appl Chem, H-3515 Miskolc, Hungary
[2] Univ Technol & Econ, Dept Phys Chem, H-1521 Budapest, Hungary
基金
匈牙利科学研究基金会;
关键词
characteristic adsorption functions (CAFs); sensitivity of CAFs to structure of adsorbents; nitrogen isotherms measured on virgin and treated; activated carbons; surface structure measured by SAXS; correlations between CAF and SAXS measurements;
D O I
10.1016/j.jcis.2004.09.026
中图分类号
O64 [物理化学(理论化学)、化学物理学];
学科分类号
070304 ; 081704 ;
摘要
A thermodynamic model of gas/solid adsorption has been constructed from two elements. The first is the original Gibbs equation. The second consists of functions psi Theta or psi (P) that are calculable from measured isotherms. Based on this model the characteristic adsorption functions (CAFs) were defined and calculated. The CAFs, which concentrate into one function all measured isotherms having the same change in relative free energy of the surface, are very sensitive to the structure of the adsorbents. This statement was tested with nitrogen isotherms measured at 77 K on well-characterized chemically/physically treated activated carbons prepared from poly(ethylene terephthalate). Changes in the surface structure were followed by small angle X-ray scattering (SAXS). This experimental approach made it possible to observe the correspondence between structural changes and the CAR (c) 2004 Elsevier Inc. All rights reserved.
引用
收藏
页码:425 / 432
页数:8
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