Page 222 - Gas Adsorption Equilibria
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208 Chapter 4
Figure 4.14. Schematic diagram of an instrument for densimetric – gravimetric measurements
of binary coadsorption equilibria without using a gas chromatograph. The sorptive
gas supplied to the system is assumed to be a binary mixture with well known
initial molar concentrations
3.2 Theory
In this section we will outline the algebraic procedure by which data for a
binary coadsorption equilibrium state, namely the masses
adsorbed on a known mass of sorbent material and the concentrations of
the sorptive gas in equilibrium with the sorbed phase can be
calculated from measured data (p, T, of a densimetric – gravimetric
experiment described in Sect. 3.1. Here we assume that the adsorption
chamber initially has been evacuated. (Step up experiments can be handled in
a fairly similar manner and do not require additional information or algebraic
procedures.)
The microbalance in working position (1), Fig. 4.12 delivers the sum of
masses adsorbed minus the buoyancy of the sorbent sample, namely the
quantity cp. Eq. (4.4)
