analysed and compared five analytical and numerical methods for the estimation of reaction rate constants
from dynamic experiments in stirred cell reactors, and a reference method was developed and suggested.
However, the methods II, III and IV summarized in his review are actually the same method from the
perspective of data numerical treatment. The reference method takes the load of the liquid bulk phase into
account and thus offers the opportunity to perform several experiments in series, without time-consuming
purification of the liquid phase. This is a good idea for the usage of a stirred cell when the load of the
liquid bulk is a little high. However, it is found that the reference method is too complex in practise and
not necessary if the liquid amount is large or the load of the liquid bulk is low.
The gas phase resistance during the absorption of a gas into a liquid in the stirred cell was not
investigated in the present literature, and it was always neglected in the measurements. Actually, as the
gas phase in the stirred cell includes liquid vapours and inert gases such as N2, it is impossible to
completely remove non-reacting gas from the stirred cell. If the partial pressure of the reactant gas is very
low and the gas absorption rate is high, the influence of the gas phase resistance on the result is
significant. For instance, with respect to the aqueous MEA+CO2 system, the CO2 partial pressure was set
very low, to about 3 5 kPa, to meet the pseudo first order reaction regime requirements, but the partial
pressure of the inert gas (MEA, H2O vapor and N2) is normally higher than this value for CO2, about 3
12 kPa. The typical absorption curve and gas, liquid statuses are shown in Figure 1.