| 摘要 |
A process for preparing ethylene oxide by reacting ethylene with oxygen in the presence of a catalyst composition comprising a support having a surface area of at least 500 m 2 /kg, and deposited on the support:
- silver metal,
- a metal or component comprising rhenium, tungsten, molybdenum or a nitrate- or nitrite-forming compound, and
- a Group IA metal or component comprising a Group IA metal having an atomic number of at least 37, and in addition potassium,
wherein the value of the expression (Q K / R) + Q HIA is in the range of from 1.5 to 30 mmole/kg, wherein Q HIA and Q K represent the quantities in mmole/kg of the Group IA metal having an atomic number of at least 37 and potassium, respectively, present in the catalyst composition, the ratio of Q HIA to Q K is at least 1:1, the value of Q K is at least 0.01 mmole/kg, and R is a dimensionless number in the range of from 1.5 to 5, the units mmole/kg being relative to the weight of the catalyst composition,
wherein a feed comprising ethylene and oxygen is contacted with the catalyst composition, and the feed comprises carbon dioxide, in addition to ethylene and oxygen, in a concentration in the range of from 0.5 to 2 mole-%, relative to the total feed. |
