Cause Of Catalyst Deactivation

Affected by various factors during use, the catalyst will lose its activity rapidly or slowly. The causes of catalyst deactivation are complex. Can be classified into the following categories:
1. Permanent inactivation
The active components of the catalyst are deactivated by the action (poisoning) of some foreign components, often permanently. Most of these foreign components are chemically reacted or ion-exchanged with the active components of the catalyst, resulting in changes in the active components. For example, the acidic catalyst is neutralized by alkali, and the noble metal catalyst is poisoned by sulfide or nitride. The deactivation of catalyst poisoning is often manifested as a rapid decline in activity. Loss of active components by abrasion or sublimation during use also leads to permanent inactivation, which is often difficult to restore simply.
2. The active components are covered and gradually inactivated, which is non-permanent inactivation. For example, the carbon deposits generated during the reaction cover the active components or block the pores of the catalyst, so that the reactants cannot contact the active components. These coverings can be removed by certain methods, such as being inactivated by carbon deposition, they can be revived by burning charcoal for regeneration.
3. Incorrect operation leads to catalyst deactivation, such as excessive reaction temperature, violent pressure fluctuations lead to confusion or crushing of the catalyst bed, etc. This type of deactivation cannot be recovered.