Direct epoxidation of propylene to propylene oxide over RuO2-CuO-NaCl-TeO2-MnOx/SiO2 catalysts

摘要

Multi-metallic RuO2-CuO-NaCl-TeO2-MnOx/SiO2 catalysts were investigated for the epoxidation of propylene to propylene oxide (PO) using O-2 under atmospheric pressure. The metallic weight ratio and the total metal loading on SiO2 support were optimized at Ru/Cu/Na/Te/Mn = 7.14/3.57/1.79/0.175/1.00 and 25.0 wt%, respectively. RuO2 and CuO were determined to exhibit a critical bifunctional role for PO synthesis. These active sites were assisted by MnOx and TeO2 to increase PO formation rate and by NaCl to reduce CO2 formation. With using the Box-Behnken design, a maximized PO formation rate of 1258 g(PO) h(-1) kg(cat)(-1) was obtained by varying O-2/propylene feed ratio and reaction temperature. (C) 2016 Elsevier B.V. All rights reserved.