From Biomass to Green Aromatics: Direct Upgrading of Furfural–Ethanol Mixtures

This work demonstrates that the production of aromatics by gas-phase Diels–Alder condensation of biomass platform molecules (furfural and ethanol) is feasible in the same terms as using chemicals from a petrochemical origin or more complex preparation procedures (as ethylene or furan). Thus, a double benefit for the environment is obtained since a waste biomass is proposed as the raw material to produce industrial high-value products by a renewable route. Experimental results with acid zeolites (ZSM-5) at 500 °C reveal total conversion and aromatic selectivities >42% (mono and bicyclic ones), with a similar catalytic stability to the most widely studied furan–ethylene system, a clear consequence that the furfural oligomerization is prevented by the prevalence of a Diels–Alder mechanism.