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Chapter 14: Experimental Determination of Transport Parameters
Table 14.2. Textural properties of a
commercial porous catalyst ICI 52/1 269
2
Specific surface 73 m /g
3
Skeletal density 3.833 cm /g
3
Apparent density 1.518 cm /g
3
Pore volume 0.377 cm /g
Porosity 0.604
Mean pore diameter 16.4 nm
1.0
dV/dlog(r) (cm 3 /g) 0.5
0.0
1 10 100 1000
r (nm)
Figure 14.18. Pore-size distribution of catalyst ICI 52/1; combination of mercury porosimetry and
physical adsorption of nitrogen
the independently obtained transport parameter set, for example, from pure diffusion
and permeation measurements, reliably predicts the experimental p rel (t) courses.
NOMENCLATURE
total molar concentration
c T
c i molar concentration of component i
c vector of molar concentrations of mixture components
D k i effective Knudsen-diffusion coefficient of component i
D m effective bulk diffusion coefficient of pair i–j
ij
D TC global effective diffusion coefficient for pair T–C
m
D ij binary bulk diffusion coefficient of pair i–j
E TC axial dispersion coeffcient of the Pair T–C
