Epoxidation of propylene to propylene oxide with molecular oxygen over Sb2O3-CuO-NaCl/SiO2 catalysts

摘要

Co-impregnated Sb2O3-CuO-NaCl/SiO2 catalysts were investigated for the direct gas-phase synthesis of propylene oxide (PO) from propylene and molecular oxygen at atmospheric pressure. The trimetallic system was optimized for PO formation by varying the Sb:Cu:Na ratios, total metal loadings and calcination temperatures. At a reaction temperature of 250 degrees C and propylene/oxygen molar ratio = 1:4, the highest performing catalyst achieved 40-45% PO selectivity with 0.4-0.7% propylene conversion without a co-feeding gas. The coexistence of Sb2O3 and CuO crystals was determined to play a vital role in propylene epoxidation, while NaCl helped to suppress combustion. (C) 2015 The Korean Society of Industrial and Engineering Chemistry. Published by Elsevier B.V. All rights reserved.