Facile production of ethyl furfuryl ether via reductive etherification of furfural over Rh nanoparticles supported red mud as a catalyst

Reducing reliance on fossil fuels and mitigating industrial waste are two strategies for clean environmental management. An active research topic within this framework is to convert abundant bio-derived compounds, like furfural (FF), into a petroleum blend by employing industrial waste, like red mud (RM), as catalyst support. Here, we demonstrate that furfural can be chemoselectively converted in a single step into ethyl furfuryl ethers (EFE), which significantly enhance the blended petroleum's octane number. This is achieved in the presence of a recyclable Rh-impregnated RM catalyst. In this context, a range of valuable metals (M = Rh, Ir, and Ru) are impregnated into the RM (M@RM) and extensively characterized by SEM, EDS, XRD, FT-IR, TEM, and XPS. The 1% Rh@RM composite, calcined at 400 °C (1% Rh@RM-400), produced 75 % EFE selectivity with the >99 % conversion of furfural. The prepared catalyst retains its stability for the multiple cycles of the furfural hydrogenation reactions.