Process for producing ethylene oxide by gas-phase oxidation of ethylene

Abstract

A process for producing ethylene oxide by gas-phase oxidation of ethylene, comprising: directing a feed comprising gaseous ethylene and gaseous oxygen through a packing of individual shaped catalyst bodies, under conditions conducive to obtain a reaction mixture containing at least 2.7 vol.-% of ethylene oxide, wherein each shaped catalyst body comprises silver deposited on a refractory support and is characterized by a content of at least 20 wt.-% of silver, relative to the total weight of the shaped catalyst body; a BET surface area in the range of 1.6 to 3.0 m/g; a first face side surface, a second face side surface and a circumferential surface with a plurality of passageways extending from the first face side surface to the second face side surface; and a uniform multilobed cross-section; and a longest direct diffusion pathway d, with 2being in the range of 0.7 to 2.4 mm, wherein the longest diffusion pathway d is defined as the shortest distance from the geometric surface of the shaped catalyst body to a point inside the structure of the shaped catalyst body for which point the shortest distance is the largest among all points. The process allows for increased activity and/or stability of the catalyst while maintaining or increasing selectivity at high productivity.