Efficient conversion of biomass-derived xylose into furfural over boron phosphate solid acid in LiBr⋅3H2O/DCM biphasic system.

Furfural is a pivotal intermediate in the biomass conversion. Therefore, the production of furfural from xylose or xylose-rich biomass has received extensive attention. Herein, a series of boron phosphate solid acid catalysts (BPs) were synthesized by self-assembly and high-temperature calcination, and used for the production of furfural from xylose or xylose-rich biomass. The results showed that the synthesized BPs was spherical nanoparticles and containing both Lewis acid and Brønsted acid sites, which was excellent for xylose conversion to furfural. The maximum furfural yield of this work was 82.8 % and achieved through 95.7 % xylose conversion by using 20 mg BP1.25 at a reaction temperature of 130 °C for 120 min with a LiBr⋅3H2O/dichloromethane (DCM) biphasic system. Noteworthy, the recycling experiments indicated that both the BP1.25 catalyst and the LiBr⋅3H2O can be reused at least four times with a furfural yield remaining ≥61.7 %. Last but not least, the prepared BP1.25 catalyst also displayed high efficiency for xylose-rich natural biomass such as corncob and bagasse conversion into furfural. The work not only developed a new system for easy conversion of xylose into furfural, but also realized the high yield production of furfural from natural biomass without components separation.