Green Synthesis of Furfural and Hydroxymethylfurfural from Various Substrates Using SupraDES under Microwave Irradiation: Techno-Economic Evaluation

The urgent need to replace fossil resources with renewable materials has driven the development of technologies to convert lignocellulosic biomass and its derived monosaccharides into valuable chemicals such as furfural (FF), 5-hydroxymethylfurfural (HMF), and levulinic acid (LA). This study employs a green and renewable solvent composed of 2-hydroxypropyl-β-cyclodextrin (HP-β-CD) and LA, a supramolecular deep eutectic solvent (SupraDES), to synthesize FF from d-xylose. Microwave irradiation (MI) and p-sulfonic acid calix[4]arene (CX4SO3H) were used as the heating method and organocatalyst, respectively. The SupraDES was characterized by using Raman spectroscopy, infrared spectroscopy, and thermogravimetric analysis. The results demonstrate the potential of this environmentally friendly system for efficient conversion of monosaccharides derived from lignocellulosic biomass, achieving a maximum yield of 70.6% of FF from d-xylose and 29.7% HMF from Dahlia tuber inulin, using heating via MI at 150 °C for 10 min, 150 mg of SupraDES, 3.0 mL of butyl acetate, and 1.0 mol % CX4SO3H. The results of the techno-economic assessment of FF production showed highly positive financial outcomes, with strong economic viability and a quick capital payback.