FACILE SYNTHESIS OF REUSABLE COAL-HYDROTALCITE CATALYST FOR DEHYDRATION OF BIOMASS-DERIVED FRUCTOSE INTO PLATFORM CHEMICAL 5-HYDROXYMETHYLFURFURAL

Abstract

A novel CoAl-hydrotalcite catalyst with different Co²⁺/Al³⁺ ratios was facilely synthesized using a modified coprecipitation method. Different techniques such as X-ray diffraction (XRD), Fourier transform-infrared (FT-IR) spectroscopy, scanning electron microscopy (SEM), and energy-dispersive X-ray (EDX) were used to characterize the resultant CoAl-hydrotalcite. It was indicated that high crystallinity and a single-phase, layered structure with good composition was successfully fabricated. The resultant CoAl-hydrotalcite catalysts and two comparative hydrotalcites (ZnAl-HT and NiAl-HT) were employed for the selective dehydration of D-fructose into platform chemical 5-hydroxymethylfurfural (HMF), which is a versatile intermediate for the production of biofuels and value-added chemicals. It was shown that the metal variation in Co²⁺/Al³⁺ ratios and reaction temperature display clear influence on the catalytic activities. Furthermore, the spent CoAl-hydrotalcite catalysts were easily recycled and show high catalytic stability over three consecutive runs.

[Supplementary materials are available for this article. Go to the publisher's online edition of Chemical Engineering Communications for the following free supplemental resources: Table S1 and Figure S1.]

Keywords:

• CoAl-hydrotalcite
• Coprecipitation method
• D-fructose
• Facile synthesis
• HMF
• Stability

Acknowledgments

This work is supported by the National Natural Science Foundation of China (50872086) and the Natural Science Foundation of Shanxi Province (2008011018).

Notes

Reaction conditions: m (D-fructose) = 0.202 g, m (catalyst) = 0.10 g, V (ethanol) = 8 mL, T = 180°C, t = 1 h, stirring speed = 1000 rpm, V (autoclave) = 28 mL, Conv.: conversion of D-fructose; Y(HMF): yield of HMF.