The Adsorption of Ozone on the Solid Catalyst Surface and the Catalytic Reaction Mechanism for Organic Components

Abstract

AbstractOzone is a strong gas oxidant and is often considered as an important source of atomic oxygen. It can not only sterilize but also decompose most organic components in water. In organic reactions, it can be used for carbon‐carbon double bond oxidation. Because ozone is unstable and easy to decompose, the oxidations usually need to be carried out in the presence of low temperature or catalysts to improve the ozone utilization. The adsorption mechanisms of ozone on the surface of solid catalysts are different due to the characteristics of the ozone molecule and the different reaction conditions. In this paper, the adsorption and reaction mechanisms of ozone on solid catalyst surface are reviewed: Firstly, the ozone has weak alkalinity similar to that of CO, but the distribution of electrons in the ozone molecule exists the difference. The difference in electron distribution makes ozone to be a dipole. The central oxygen atom can accept electrons as the Lewis acid, while the terminal oxygens are electron donors to be the Lewis base. Secondly, the functional groups, which have Lewis acid and base sites, such as hydroxyl groups, can be adsorbed with the central or terminal oxygen of ozone to form a surface complex. Last, the solvents also have a critical effect on the adsorption of ozone and subsequent oxidation. According to the above mechanisms, the design and preparation of ozonation catalysts are also proposed to improve the ozonation selectivity.