Effect of ZSM-5 acidity on aromatic product selectivity during upgrading of pine pyrolysis vapors

- ZSM-5 of varying acidities produced aromatics from biomass pyrolysis vapors.
- Product selectivity and yield are affected by acid site density.
- Increasing catalyst acidity decreases selectivity toward substituted aromatics.
- Selectivity to 2- and 3-ring aromatics increases with increasing catalyst acidity.