Efficient biomass valorization using silica supported imidazolium based ionic liquid catalysts

The efficient valorization of lignocellulosic biomass (LCB) into high-value platform chemicals such as 5-hydroxymethylfurfural (5-HMF) and furfural offers a sustainable alternative to fossil-based resources. In this study, we report the design and application of efficiently recyclable, silica-supported imidazolium-based acidic ionic liquid (IL) heterogeneous catalysts for the conversion of real, extracted cellulose and hemicellulose derived from wheat straw, rice husk and bagasse. The synthesized catalysts were extensively characterized using FTIR, XRD, TGA, BET and their Brønsted acidity was quantified. Catalytic activity was optimized by evaluating key reaction parameters, including catalyst loading, time, and temperature. Under mild operational conditions (80 °C for cellulose and 120 °C for hemicellulose), high yields of 5-HMF (91%) and furfural (86%) were achieved. The catalysts also demonstrated excellent recyclability over five consecutive reaction cycles without significant loss in activity. This study offers a scalable and environmentally benign approach for biomass valorization, highlighting the potential for industrial implementation.