How Does Pore Size Distribution Affect Catalytic Performance?
The pore size distribution of a catalyst affects its performance in several ways:
- Accessibility to Active Sites: Micropores provide a high surface area but may restrict the diffusion of larger molecules, while mesopores and macropores offer better accessibility for larger reactants. - Mass Transfer Limitations: An optimal balance of different pore sizes can minimize mass transfer limitations, thereby improving the rate of reaction. - Selectivity and Activity: Tailoring the pore size distribution can enhance the selectivity of a catalyst towards specific products. For instance, mesoporous materials are often used in reactions involving bulky molecules. - Stability: A well-distributed pore size can help in maintaining the structural integrity of the catalyst under reaction conditions, thus enhancing its stability and lifespan.
