Oxidation: Many catalysts, especially metal-based ones, can undergo oxidation when exposed to air. This can alter their surface properties and reduce their catalytic activity. Deactivation: Prolonged exposure to air can deactivate some catalysts. For example, catalysts used in hydrogenation reactions can form oxides that are less active or inactive. Structural Changes: Air exposure can cause physical changes such as sintering, where particles agglomerate and lose surface area, which is crucial for catalytic activity. Contamination: Airborne contaminants can deposit on the catalyst surface, blocking active sites and reducing efficiency.
