Facile Preparation of a Magnetic Zr-MOF Nanocomposite (Fe₃O₄@SiO₂@UiO-66- NH₂(Zr)) as an Efficient Catalyst for High-Yield Conversion of Fructose to 5- Hydroxymethylfurfural.

Abstract

The conversion of biomass-derived carbohydrates into valuable platform chemicals is a pivotal strategy for sustainable chemical production. In this study, we developed a functionalized magnetic nanocatalyst, Fe₃O₄@SiO₂@UiO-66-NH₂(Zr), by integrating amino-functionalized zirconium-based metal-organic framework (UiO-66-NH₂(Zr)) with silica-coated magnetite nanoparticles (Fe₃O₄@SiO₂) through a facile one-pot synthesis approach. This design leverages the magnetic separability of Fe₃O₄, the protective silica shell, and the high porosity and Lewis acidity of UiO-66-NH₂(Zr) to enhance catalytic efficiency and recyclability in the dehydration of fructose to 5-hydroxymethylfurfural (5-HMF), a versatile bio-based intermediate for fuels and polymers. The nanocomposite was thoroughly characterized using X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), energy-dispersive X-ray spectroscopy (EDS), and field emission scanning electron microscopy (FE-SEM), confirming successful integration, crystalline structure, and uniform morphology with particle sizes ranging from 20-50 nm. Catalytic performance was evaluated in aqueous media under optimized conditions, with 5-HMF quantification performed via UV-Vis spectroscopy and high-performance liquid chromatography (HPLC). Under mild reaction conditions (100 °C, 3 h), the catalyst achieved an exceptional 95% yield of 5-HMF from fructose, outperforming bare UiO-66-NH₂(Zr) and demonstrating excellent selectivity (>98%). This work highlights the potential of hybrid MOF-magnetic nanocomposites for efficient, eco-friendly biomass valorization, paving the way for scalable industrial applications.