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Furfural chemistry is one of the most promising platforms directly derived from lignocellulose biomass. In this study, a niobium-based catalyst (mNb-bc) was synthesized by a new fast and simple method. This new method uses microemulsion to obtain a catalyst with a high specific surface area (340 m 2 g –1 ), defined mesoporosity, and high acidity (65 μmol g –1 ). Scanning electron microscopy revealed that mNb-bc has a rough surface. The mNb-bc was used to catalyze the conversion reaction of xylose into 2-furfuraldehyde in a monophasic system using water as a green solvent. This reaction was investigated using a 2 3 experimental design by varying the temperature, time, and catalyst-to-xylose ratio (CXR). The responses evaluated were xylose conversion ( X c ), reaction yield ( Y ), and selectivity to 2-furfuraldehyde ( S ). The optimized reaction conditions were used to evaluate the reaction kinetics. At milder reaction conditions of 140 °C, 2 h, and a CXR of 10%, mNb-bc led to an X c value of 41.2%, an S value of 77.1%, and a Y value of 31.8%.

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Mesoporous catalysts were synthesized from the precursor NbCl 5 and surfactant CTAB (cetyltrimethylammonium bromide), using different synthesis routes of, in order to obtain materials with different properties which are capable of promoting the epoxidation of cyclohexene. The materials were characterized by X ray diffractometry (XRD), thermogravimetry (TG), acidity via pyridine adsorption, Hammet titration and N 2 adsorption/desorption. The characterization data indicate that the calcination process of the catalysts was efficient for elimination of the surfactant, but it caused a collapse of the structure, causing a Brunauer Emmett Teller (BET) specific area decrease (ClNbS-600, 44 and ClNbS-AC-600, 64 m 2 g −1). The catalysts that have not been calcined showed high BET specific areas (ClNbS 198 and ClNbS-AC 153 m 2 g −1). Catalytic studies have shown that mild reaction conditions promote high conversion. The catalysts ClNbS and ClNbS-AC showed high conversions of cyclohexene, 50 and 84%, respectively, while the calcined materials showed low conversion (<30%). The epoxide formation was confirmed by nuclear magnetic resonance (NMR).