Heterogeneously Catalyzed Oxidation Reactions Using ... - CHEC

5.3 Results
two association sites on benzaldehyde were estimated capable of cross‐associating with water only.
The cross association parameters were estimated with the modified CR‐1 combining rule. Finally, one
cross‐association site was estimated on CO2 to only cross‐associate with benzyl alcohol for the last
system (entry 4). Further details can be found in ref. [29]. Since the model performed satisfactorily
for binary systems, ternary systems were modeled in the next step.
Table 5‐4: Fitted kij and βcross values for binary systems with cross association.
Entry Compound 1 Compound 2 kij
137
βcross
Temperature
range (°C)
1 CO2 H2O 0.15476 0.02362 80
2 H2O Benzyl alcohol 0.00841 0 20 – 150
3 H2O Benzaldehyde ‐0.06387 0.13074 25 – 147
4 CO2 Benzyl alcohol
‐0.063819 +
8.353∙10 ‐4 ∙ T
(K)
0.26337 60 – 180
5.3.3 Application of the CPA equation of state for phase behavior modeling
The binary interaction parameters between the relevant compounds allowed the prediction of the
phase behavior of ternary mixtures, i.e. benzyl alcohol – O2 – CO2 representing the substrate mixture
and benzaldehyde – H2O – CO2 representing the product mixture at 100 % conversion and 100 %
selectivity. The phase behavior predictions were accompanied by measuring dew points
experimentally.
(a) (b)
Figure 5‐3: CPA Equation of State predictions (lines) and experimental data (points) for the phase transitions
of the ternary systems benzyl alcohol – O2 – CO2 (a) and benzaldehyde – H2O – CO2 at catalysis‐relevant
conditions and compositions.