Ethylene oxide (EO) degradation over Ag/alpha-Al2O3 catalysts involves bifunctional pathways, whereby alpha-Al2O3 surfaces catalyze hydration, isomerization, dimerization, and oxidation while Ag surfaces facilitate combustion and isomerization of ethylene oxide. EO degradation reactions run over Ag/alpha-Al2O3, alpha-Al2O3, and intrapellet mixtures thereof with co-feeds of O-2 and oxygenate products show that Ag surfaces are more reactive than alpha-Al2O3 and that oxygenate products generated over alpha-Al2O3 combust over Ag much more (>30x) readily than EO. These observations suggest that additives which mitigate surface hydration of alpha-Al2O3 and combustion activity of Ag will most effectively mitigate EO degradation. (C) 2020 Elsevier Inc. All rights reserved.