Phosphotungstic acid supported on Zr-SBA-15 as an efficient catalyst for one-pot conversion of furfural to ?-valerolactone

Development of high-performance solid catalysts for the utilization of biomass has become an important research topic in heterogeneous catalysis and sustainable chemistry. Herein, A series of phosphotungstic acid (HPW) supported on Zr-SBA-15 were prepared by a post-synthesis procedure and evaluated for the one-pot conversion of furfural (FUR) to ?-valerolactone (GVL) using 2-propanol as the H-donor and solvent. Those catalysts were detailed and characterized by XRD, N2 physisorption, FTIR, SEM, TEM, NH3-TPD, and pyridine-DRIFT techniques. Among those catalysts, a complete conversion of FUR was achieved, while the selectivity of GVL was significantly affected by the ratio of HPW and Zr. The HPW/Zr-SBA-15 (2-4-15) (the mass ratio of HPW: ZrOCl2: SBA-15 = 2:4:15) showed the highest GVL yield (83%) under optimized reaction conditions. Correlating the catalyst performance with the B/L ratio (Bronsted acid sites (BAS)/Lewis acid sites (LAS)) ratio uncovers that the balance between the BAS and LAS would be the key to higher catalytic performance. Different reaction parameters including reaction temperature, time, and FUR concentration were also studied. In addition, the catalyst showed good stability and regeneration.

Automated summary

In this study, high-performance solid catalysts based on phosphotungstic acid (HPW) supported on Zr-SBA-15 were synthesized and evaluated for the one-pot conversion of furfural (FUR) to γ-valerolactone (GVL). The catalysts were characterized using various techniques, and the ratio of HPW and Zr was found to significantly affect the selectivity of GVL. The HPW/Zr-SBA-15 (2-4-15) catalyst exhibited the highest GVL yield (83%) under optimized reaction conditions, and it was determined that a balance between Bronsted acid sites (BAS) and Lewis acid sites (LAS) was crucial for achieving higher catalytic performance. The reaction parameters and catalyst stability were also investigated.