Dehydration of carbohydrates into 5-hydroxymethylfurfural over vanadyl pyrophosphate catalysts

The catalytic activity of a series of vanadyl pyrophosphate (VPP) catalysts with different loadings supported on mesoporous silica KIT-6 was investigated for the dehydration of glucose and fructose into 5-hydroxymethylfurfural (5-HMF). The active phase was synthesized by V2O5 reduction in an alcoholic media followed by calcination of VOHPO4.0.5H(2)O precursor at 400 degrees C. The catalysts were characterized by FT-IR spectroscopy, Raman spectroscopy, ICP-OES, X-ray diffraction (XRD), N-2 adsorption-desorption analysis, and temperature-programmed desorption (NH3-TPD) techniques as well as SEM, TEM, and X-ray photoelectron spectroscopy (XPS). Among the catalysts, the one containing the lowest percentage of VPP exhibited the best activity in the dehydration reaction. The effect of different parameters such as the loading amount of VPP on the support, the initial amount of carbohydrates and catalyst, reaction temperature, time, and solvent was studied. The highest yields of 5-HMF were obtained to be 79% (145 degrees C/ 1 h) and 48% (185 degrees C/1.5 h) for the fructose and glucose dehydration, respectively. Catalysts were simply separated via centrifugation without significant changes in catalytic activity and reused for additional four runs. (C) 2020 Elsevier Ltd. All rights reserved.

Automated summary

The catalytic activity of vanadyl pyrophosphate (VPP) catalysts supported on mesoporous silica KIT-6 for glucose and fructose dehydration into 5-hydroxymethylfurfural (5-HMF) was investigated, and the catalyst with the lowest VPP loading exhibited the best activity. Various parameters such as VPP loading amount, initial amount of carbohydrates and catalyst, and reaction conditions were found to have an impact on the catalytic activity.