Page 63 - Gas Adsorption Equilibria

1. Basic Concepts 49

As can be recognized, the micropore volume of the carbon is reduced by
the impregnation, but again increased by the pyrolysis procedure. Note also
that the average pore radius is somewhat shifted to a lower value by the
impregnation but again increases after pyrolysation [1.36].

Figure 1.16. Micropore volume distribution function of activated carbon ACTW 52 and certain
of its modifications calculated from adsorption data by the DR-method [1.3,
1.59].

Data of the total micropore volume and of the BET
surface of the four activated carbons are given in Table 1.6.

In many applications of porous sorbent materials to gas adsorption
problems, especially in drying and air conditioning processes, the behavior of
the sorbent in the presence water vapor is of importance. Figure 1.17 shows a
set of adsorption isotherms describing the amount of water vapor adsorbed per
unit mass of sorbent at given pressure and temperature of the vapor.
Measurements were taken at t = 298,15 K = 25 °C (saturation pressure:
for relative pressures [1.39, p. 2537]. These