Dubinin-Radushkevich - Micromeritics ASAP 2020 Confirm Operator's Manual

ASAP 2020 Confirm

Dubinin-Radushkevich

The Dubinin-Radushkevich
log
where:
V
Vo
Po
P
B

T
For each point designated for Dubinin-Radushkevich calculations, the following calculations
are done:
LV = log (V)
LP
The intercept, log(Vo) can be found by performing a least-squares fit on the (LP,LV) desig-
nated pairs where LP is the independent variable and LV is the dependent variable. Assuming
the adsorption of gas is restricted to a monolayer, Vo is the monolayer capacity. Based on this
assumption, the following are calculated:
a. Slope (S cm
b. Y-intercept (YI cm
c. Error of the slope (S
d. Error of the y-intercept (YI
e. Correlation coefficient (Cc)
1. Dubinin, M., Carbon 21, 359 (1983); Dubinin, M., Progress in Surface and Membrane Science 9, 1, Academic
Press, New York (1975); Dubinin, M. and Astakhov, V., Adv. Chem. Ser. 102, 69 (1971); Lamond, T. and
Marsh, H., Carbon 1, 281, 293 (1964); Medek, J., Fuel 56, 131 (1977); Polanyi, M., Trans. Faraday Soc. 28,
316 (1932); Radushkevich, L., Zh. fiz. Kemi. 33, 2202 (1949); Stoeckli, H., et al, Carbon 27, 125 (1989).
C-30
1 equation is as follows:
2

B T
V    
-------------- -
= log Vo –

= volume adsorbed at equilibrium pressure (cm
= the micropore capacity (cm
= saturation vapor pressure of gas at temperature T (mmHg)
= equilibrium pressure (mmHg)
= a constant
= the affinity coefficient of analysis gas relative to Po gas
(for this application  is taken to be 1)
= analysis bath temperature (K), from the Po and Temperature
Options dialog
2
Po
 
------ -
= log
 
P
3
/g STP)
3
/g STP)
cm
ERR
2
Po

log ------ -
P
3
/g STP)
3
/g STP)
3
cm /g STP)
ERR
Appendix C
3 /g STP)
202-42811-01 - Mar 2011