A PROCESS FOR INITIATING A HIGHLY SELECTIVE ETHYLENE OXIDE CATALYST

摘要

A start-up process for epoxidation of ethylene is provided. The process includes initiating an epoxidation reaction by reacting a feed gas composition in the presence of an epoxidation catalyst at a first temperature of about 180 °C to about 210 °C. The first temperature is increased to a second temperature of about 230°C to about 290°C, over a time period of about 6 hours to about 50 hours, while simultaneously adding a sufficient concentration of moderator so that the amount of moderator adsorbed on the catalyst after achieving the second temperature is from about 10 to about 50 g/m3 of catalyst. The second temperature is maintained for about 50 hours to about 350 hours, while regulating the feed gas composition to contain about 0.5% to about 25% CO2. The second temperature is decreased to a third temperature, while simultaneously increasing moderator concentration to a level greater than the sufficient concentration.