Hydrogenation of Furfural to Furfuryl Alcohol over PdCu/zirconium Phosphonate with Metal and Lewis Acid Sites

Graphical Hydrogenation of furfural to furfuryl alcohol under H 2 and N 2 atmosphere are studied over PdCu/ZrPO with metal and Lewis acid sites. The PdCu metal active sites of PdCu/ZrPO involve both direct hydrogenation and transfer hydrogenation activities, and the Zr 4+ −O 2− Lewis acid-basic pairs of ZrPO have transfer hydrogenation activity. Hydrogenation of furfural to furfuryl alcohol under H 2 and N 2 atmosphere was studied over zirconium phosphonate (ZrPO)-supported PdCu (PdCu/ZrPO) catalysts. The direct hydrogenation and transfer hydrogenation activities of PdCu metal active sites and the transfer hydrogenation activity of Zr 4+ −O 2− Lewis acid-basic sites were investigated, respectively. The size and the distribution of Cu particles could be adjusted by altering the P/Zr molar ratio. Bimetallic PdCu could enhance the acidity of the PdCu/ZrPO catalysts, and improve the ratio of Lewis/Brønsted acid, which led to an increase in the transfer hydrogenation activity of Lewis acid-basic pairs. The electronic effect between Pd and Cu promoted furfural to absorb onto electron-deficient Cu through η1(O)-aldehyde configuration, which contributed to the direct hydrogenation and the transfer hydrogenation at metal active sites. Especially, the adsorption and dissociation of H 2 in electron-rich Pd were promoted, which significantly improved the direct hydrogenation activity.