Xylulose to furfural: a mathematical modeling assessment of a new route to produce a high yield of furan

Biomass has the potential to serve as a renewable feedstock for the production of a wide range of fuels and chemicals. Furfural, which is currently made from waste biomass, is a very versatile and key platform chemical for the synthesis of, among others, 2-methylfuran, gasoline and diesel components. Current production methods are limited in the efficiency of furan production due to incomplete conversion of the xylose as well as undesired byproduct and humin formation. In an effort to increase the yield and selectivity of furfural production, we have produced furfural from xylulose, the ketose isomer of xylose. Production of furfural directly from xylulose has not been considered a viable option due to the excessive cost of high purity xylulose. However, we have developed a method of simultaneous isomerization and reactive extraction (SIRE) for producing concentrated xylulose at high purity. Using this xylulose-rich media, we have achieved high-yield, high-selectivity production of furfural under relatively low temperature conditions. We have evaluated several potential reaction models to determine the reaction kinetics of the xylulose dehydration and side reactions that affect furfural yield in different reaction media. By comparing the predictions of the models to experimental data on xylulose dehydration, we have been able to determine the most probable reaction mechanisms as well as optimal conditions for furfural production from xylulose.