Intracage chemistry: nitrite to nitrate oxidation via molecular oxygen. A Car Parrinello study.

Ettore Fois, Aldo Gamba, Gloria Tabacchi
  • January 2001, Elsevier
  • DOI: 10.1016/s0167-2991(01)80154-3

Oxidation of nitrite via molecular oxygen

What is it about?

The oxidation of nitrite to nitrate via molecular oxygen occurs at high temperature inside porous industrial catalysts named zeolites. However, the mechanism was obscure. We modelled this reaction with accurate computer simulations. We found that confinement in zeolite pores is key for the reaction, because the framework helps to break the oxygen molecule.

Why is it important?

Many industrial reactions involving zeolites occur at high temperature in oxidizing conditions, so it is important understand how these materials behave. We found that interactions of molecular oxygen in the zeolite cage may reduce the energy gap between triplet and singlet states. For this reason, molecular oxygen can have a different reactivity in oxidation reactions when it is confined in porous materials like zeolites.

Perspectives

Gloria Tabacchi
university of insubria

Although we tackled this problem long time ago, I think that some important issues are still open. For example, we have still much to learn about the reactivity of triplet molecular oxygen and its conversion to singlet oxygen. In this work, we suggested that the very reactive singlet oxygen could be stabiilized by the zeolite. Also, our result showed that the zeolite framework does take active part to the chemical reactions inside the pores.

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http://dx.doi.org/10.1016/s0167-2991(01)80154-3

The following have contributed to this page: Gloria Tabacchi