Acetone Photodegradation Kinetic Modeling

On this basis and given the expected negligible carbon dioxide adsorption, the following relationships are proposed  

TABLE 8.1. Optimized Parameters for Acetone Data Modeling 

The proposed model appears to be adequate to monitor the changes in acetone concentration in the gas phase during the photoconversion experiments. 

The evaluated parameters of rAc.g at the initial reaction conditions (t = 0), are 115 /xmole m min for Hombikat UV-100 and 130 /rmole m - min for Degussa P25. Considering the relation between and (equation 8-5), this yields a total acetone initial reaction rate of 125 /imole m min and 137 /rmole m min for Hombikat UV-100 and Degussa P25 respectively. 

It can thus be concluded that under the conditions of reaction testing in Photo-CREC-Air, both Hombikat UV-100 and Degussa P25 display a close photoactivity. 

---

When the fitted parameters are used to calculate carbon dioxide formation, it can be observed that the proposed model consistently predicts a faster carbon dioxide formation rate than the one observed experimentally (Figure 8.5b). Only towards the end of the experiments does the cumulative measured CO2 become higher than the model predictions. This phenomenon, not noticed in the case of acetone photodegradation, suggests some failure of the kinetic model assumptions. One possible explanation is the... 

---