A modeling and experimental study on hydrothermal aging deactivation of NO oxidation activity on Pt-Pd catalyst

A state-of-the-art Pt-Pd catalyst was hydrothermally treated at different conditions to investigate hydrothermal stability of NO oxidation. NO oxidation reactor data was collected on catalysts that have been hydrothermally treated at temperatures ranging from 550 degrees C until 1100 degrees C. NO oxidation activity was observed to decrease with increase in aging duration at all the aging temperatures. A global kinetic model of NO oxidation was used to estimate the change in NO oxidation rate when subjected to different hydro-thermal aging conditions. Model estimated normalized rates at multiple hydro-thermal aging conditions were used to develop a hydro-thermal aging model of NO oxidation. A deactivation Model with Residual Activity (DMRA) was developed to capture the impact of hydrothermal aging temperature and duration on NO oxidation activity. A global kinetic model that accounts for change in PGM oxidation state during NO oxidation has also been presented.

Automated summary

A state-of-the-art Pt-Pd catalyst was hydrothermally treated at different conditions to investigate the hydrothermal stability of NO oxidation. The NO oxidation activity was observed to decrease with an increase in aging duration at all aging temperatures. A global kinetic model of NO oxidation was used to estimate the change in NO oxidation rate under different hydrothermal aging conditions, and a deactivation Model with Residual Activity (DMRA) was developed to capture the impact of hydrothermal aging temperature and duration on NO oxidation activity. Additionally, a global kinetic model that accounts for the change in PGM oxidation state during NO oxidation has been presented.