Catalysis Today 175 (2011) 524–527 Contents lists available at ScienceDirect Catalysis Today j ourna l ho me p ag e: www.elsevier.com/lo cate/cattod Defunctionalization of fructose and sucrose: Iron-catalyzed production of 5-hydroxymethylfurfural from fructose and sucrose Xinli Tong a , Mengran Li a , Ning Yan b , Yang Ma a , Paul J. Dyson b , Yongdan Li a,∗ a Tianjin Key Laboratory of Catalysis Science and Technology and State Key Laboratory for Chemical Engineering (Tianjin University), School of Chemical Engineering, Tianjin University, Tianjin 300072, China b Institut des Sciences et Ingénierie Chimiques, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland a r t i c l e i n f o Article history: Received 12 October 2010 Received in revised form 15 February 2011 Accepted 1 March 2011 Available online 9 April 2011 Keywords: Fructose Sucrose 5-Hydroxymethylfurfural Iron catalysis Biomass transformation a b s t r a c t A highly efficient iron-catalyzed production of 5-hydroxymethylfurfural (HMF) from sugar is reported. The dehydration of fructose and sucrose has been studied in the presence of different iron salts and co-catalysts. As a result, it was found that fructose and sucrose could be efficiently and selectively con- verted to HMF using a combination of environmentally friendly FeCl 3 and tetraethyl ammonium bromide (Et 4 NBr) as the catalytic system. For instance, 86% HMF yield at full conversion of fructose was obtained for 2 h at 90 ◦ C in air. The effects of catalyst concentration, reaction time and reaction temperature were investigated in detail. The electronic absorption spectra of different catalysts were recorded, and the FeCl 3 Br - ion was considered as the active catalyst species. © 2011 Elsevier B.V. All rights reserved. 1. Introduction The use of biomass as a source of liquid fuels and chemi- cals represents a sustainable approach for obtaining energy and carbon-based compounds [1–3]. Conversion of sugars, such as fruc- tose and sucrose, to valuable chemicals is very important in the chemical processing from biomass resources [4–6]. The impor- tant compound 5-hydroxymethylfurfural (HMF), which originates from the dehydration of sugar, is a valuable intermediate used in the production of fine chemicals, pharmaceuticals and numer- ous polymers [7–9]. In recent years, the development of novel and efficient catalytic systems for the dehydration of sugars to HMF has become a hot topic [10–12]. Traditionally, acid cata- lysts, such as mineral acids [13,14], strong acid cation exchange resins [15–17], H-form zeolites [18,19], and supported heteropoly- acids [20], have been employed for the dehydration fructose to HMF. In addition, acidic ionic liquids have been used as catalysts or solvents in sugar dehydration [21–24]. However, these cata- lysts may have favored the subsequent dehydration of HMF to levulinic and formic acids, which ultimately lowers the yield of HMF [25,26]. Recently, the metal-catalyzed dehydration of sugar has received considerable attention due to the high selectivity of HMF that ∗ Corresponding author. Tel.: +86 022 27405613; fax: +86 022 27405243. E-mail address: ydli@tju.edu.cn (Y. Li). may be achieved with negligible acid by-product. For example, Zhao et al. [27] have reported a metal chloride/1-ethyl-3-methyl- imidazolium chloride ([EMIM]Cl) system that gives moderate to good HMF yields from fructose (ca. 83% with Pt or Rh chloride) and glucose (ca. 68% with CrCl 2 ); Yong et al. [28] further found that a system based on N-heterocyclic carbene- Cr/1-butyl-3-methyl imidazolium chloride ([BMIM]Cl) was more efficient for the dehydration of sugars to HMF. However, in these catalytic systems, only noble metals (Ru and Pt chlo- ride) or potentially toxic metals (Cr chlorides) resulted in a good catalytic performance. It is well-known that developing more cost-efficient and environmentally friendly metal catalysts remains an issue of scientific interest and industrial significance. In this respect, iron salts are ideal candidates due to their low cost, non-toxicity, ready availability and environmentally benign character [29,30]. Iron-based catalysis is effective in the cross-coupling [31–33], oxidation [34,35] and hydrogenation reaction [36], as well as in the Fischer–Tropsch synthesis [37]. However, iron-catalyzed sugar conversion remains a challenge and warrants further investiga- tion. In this paper, we describe the iron-catalyzed dehydration of fructose and sucrose to HMF. It was found that a FeCl 3 –tetraethyl ammonium bromide (Et 4 NBr) system resulted in a high catalytic performance and HMF was obtained in good yield under mild conditions. Moreover, the catalytic system was further optimized and attempts to delineate the nature of the active catalyst were made. 0920-5861/$ – see front matter © 2011 Elsevier B.V. All rights reserved. doi:10.1016/j.cattod.2011.03.003