Magnetic Nanohybrid Decorated Porous Organic Polymer: Synergistic Catalyst for High Performance Levulinic Acid Hydrogenation

Herein we have developed a highly active, robust, and selective porous organic polymer (PPTPA-1, POP) encapsulated magnetically retrievable Pd-Fe3O4 nanohybrid catalyst in a one-step solvothermal route and investigated its catalytic performance in levulinic acid (LA) hydrogenation, a key platform molecule in many biorefinery schemes, to gamma-valerolactone (GVL), employing formic acid as sustainable H-2 source. The specific textural and chemical characteristics of as-synthesized nanohybrid materials were identified by XRD, XPS, FT-IR, C-13 CP MAS NMR, HR-TEM, and FE-SEM with the corresponding elemental mapping and nitrogen physisorption studies. It was found that the nanohybrid Pd-Fe3O4/PPTPA-1 catalyst exhibited a substantially enhanced activity in comparison with the monometallic catalysts (Pd/PPTPA-1 and Fe3O4/PPTPA-1). Evidence of the electronic interaction between Pd and Fe attributable to the intrinsic hybrid synergistic effect is thought to be responsible for this superior catalytic performance and improvement in catalyst stability. The recycling experiments revealed that the magnetic nanohybrid catalyst sustained remarkable recycling efficiency and magnetism after being used in 10 successive catalytic runs, which made Pd-Fe3O4/PPTPA-1 a potential catalyst for the production of GVL in industry.