Synthesis of porous organic polymer-based solid-acid catalysts for 5-hydroxymethylfurfural production from fructose

Herein, we report the synthesis of nanoporous polytriphenylamine polymers (PPTPA) by a simple one-step oxidative polymerization pathway and the materials were sulfonated with chlorosulfonic acid to introduce acidic sulfonic groups to the polymers to form solid acid catalysts (SPPTPA). Magnetic properties were added to SPPTPA catalysts by depositing Fe₃O₄ nanoparticles to develop (FeSPPTPA) solid acid catalysts, for performing dehydration of fructose to 5-hydroxymethylfurfural (HMF), which is regarded as a sustainable source for liquid fuels and commodity chemicals. XRD, FTIR spectroscopy, SEM, TGA, and N₂ sorption techniques were used to characterize synthesized materials. The FeSPPTPA80 nanocatalyst showed superior catalytic activities in comparison to other catalysts due to the nanorods that formed after sulfonation of the PPTPA polymeric material which gave the catalyst enough catalytic centers for dehydration reaction of fructose. The recyclability tests revealed that the magnetic solid acid catalysts could be reused for four consecutive catalytic runs, which made FeSPPTPA a potential nanocatalyst for production of HMF.