文摘
A series of monometallic Pt and Pd and alloyed Pt鈥揚d catalysts (mole ratio of Pt/Pd = 1, 4, and 0.25) were prepared with silica鈥揳lumina as support. CO chemisorption and X-ray diffraction (XRD) were applied to characterize the resulting samples. The performance of the catalysts for hydrodeoxygenation (HDO) for benzofuran (BF) was evaluated in a fixed-bed flow reactor at 280 掳C and 3.0 MPa. Only one major route was found for the reaction network of HDO of BF among the catalysts. First, BF was transformed to 2,3-dihydrobenzofuran with the hydrogenation at the heterocyclic ring, followed by further conversion to octahydrobenzofuran at the benzene ring. The main hydrocarbon products are ethylcyclohexane and methylcyclohexane. The silica鈥揳lumina-supported catalysts also showed significant cracking activities, with the observation of the production of methylcyclohexane. The activity and product selectivity of Pt, Pd, and bimetallic Pt鈥揚d catalysts with the influence of the weight time were investigated in detail. Bimetallic Pt鈥揚d catalysts were higher in activity in the hydrogenation and the removal of oxygen from BF than their monometallic counterparts. The Pd4Pt1 catalyst presented the highest activity, with 99% conversion of BF and 100% selectivity toward 2,3-dihydrobenzofuran among all of the other catalysts at low weight time.