Dubinin-Radushkevich - Micromeritics ASAP 2460 Operator's Manual

ASAP 2460 Operator's Manual

Dubinin-Radushkevich

The Dubinin-Radushkevich
 
log Q =
where:

=
B =
Po =
P =
Q =
Q =
0
T =
For each point designated for Dubinin-Radushkevich calculations, the following calculations are done:
 
LV = log

LP = log

The intercept, log(Vo) can be found by performing a least-squares fit on the (LP,LV) designated 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
Using the results of the above calculations, the following can be calculated:
Monolayer Capacity (cm
YI
Q = 10
0
246-42800-01 - Aug 2013
13
equation is:
2
BT
Po
  --------- 
log Q – log ------ -
0

the affinity coefficient of analysis gas relative to Po gas (for this application 
is taken to be 1)
a constant
saturation vapor pressure of gas at temperature T
equilibrium pressure
quantity adsorbed at equilibrium pressure (cm
the micropore capacity (cm
analysis bath temperature (K), from the Po and Temperature Options win-
dow
Q
2
Po

------ -

P
3
/g STP)
3
/g STP)
3
cm /g STP)
err
3
cm /g STP)
err
3
/g STP):
2
P
3
/g STP)
Appendix C
3
/g STP)
C-37