Improving the selectivity to C4 products in the aldol condensation of acetaldehyde in ethanol over faujasite zeolites

- NaX and NaY can be selective for aldol condensation of acetaldehyde to C4 products.
- At 230 °C, higher C4/(C6 + C8) product ratio is produced over NaY than over NaX.
- A confinement effect observed when adding K ions to N.
- NaY and NaX zeolites.
- Cage accessibility varied by alkali addition greatly influences C4 selectivity.