One pot selective conversion of furfural to γ-valerolactone over zirconia containing heteropoly tungstate supported on β-zeolite catalyst

A series of metal oxide and tungstophosphoric acid (TPA) supported on beta-zeolite catalysts were prepared and evaluated for the one pot selective conversion of furfural (FA) to gamma-valerolactone (GVL) using transfer hydrogenation approach. The characterizations of the catalysts were derived from N-2 -adsorption, FT-IR, XRD, XPS and temperature programmed desorption (TPD) techniques. The acid and base sites in the catalysts were estimated by NH3 and CO2-TPD and FT-IR spectroscopy with pyridine and 2-propanol adsorption. Among the catalysts 20%ZrO2 with 5%TPA on beta-zeolite showed high activity with 85% GVL yield. The high Lewis acidic density along with basic sites are responsible for the outstanding catalytic activity of the catalyst. Based on product distribution and catalyst characteristics, a plausible mechanism was proposed. Different reaction parameters were also studied and optimum conditions were established. The catalyst was easily recovered and reused with consistent activity.