Batch and continuous-flow room temperature furfural acetalization with ethanol over aluminophosphate (APAl) catalysts for biofuels production

The acetalization of furfural and ethanol was investigated over aluminophosphate (APAl) catalysts using both batch and flow reaction systems to produce furfural diethyl acetal (FDA). APAl catalysts were synthesized with varying P/Al ratios and calcination temperatures to study their effects on Brønsted acid active sites for the reaction. Catalysts were characterized by N2 adsorption and Pyridine (PY) and 2,6-dimethylpyridine (DMPY) pulse chromatography titration. A maximum of 89 % furfural conversion and >99 % selectivity of FDA was obtained for the best catalyst (APAl-85/15-A-773) under batch conditions within 30 min at room temperature. On the other hand, the flow system provided a maximum of 92 % furfural conversion. APAl-85/15-A-773 catalyst was also reusable, highly stable, and exhibited a high catalytic performance for furfural acetalization with ethanol at room temperature. © 2022 Elsevier Ltd