Process for the production of an olefin oxide, a 1,2-diol, a 1,2-diol ether, a 1,2-carbonate, or an alkanolamine

1. A process for the epoxidation of an olefin comprising:

contacting a reactor feed comprising an olefin, oxygen, and carbon dioxide, with a catalyst comprising a carrier and, deposited on the carrier, silver, a rhenium promoter, a first co-promoter, and a second co-promoter; wherein

the carbon dioxide is present in the reactor feed in a quantity of at most 3 mole percent based on the total reactor feed;

the first co-promoter is selected from the group consisting of sulfur, phosphorus, boron, and mixtures thereof; and

the second co-promoter is selected from the group consisting of tungsten, molybdenum, chromium, and mixtures thereof.

2. The process as claimed in claim 1 , wherein the quantity of carbon dioxide is less than 2 mole percent based on the total reactor feed.

3. The process as claimed in claim 1 , wherein the quantity of carbon dioxide is in the range of from 0.2 to less than 1.5 mole percent based on the total reactor feed.

4. The process as claimed in claim 1 , wherein the olefin is ethylene.

5. The process as claimed in claim 1 , wherein the second co-promoter comprises tungsten.

6. The process as claimed in claim 1 , wherein the second co-promoter comprises molybdenum.

7. The process as claimed in claim 1 , wherein the first co-promoter comprises sulfur.

8. The process as claimed in claim 1 , wherein the catalyst further comprises a further element selected from the group consisting of nitrogen, fluorine, alkali metals, alkaline earth metals, titanium, hafnium, zirconium, vanadium, thallium, thorium, tantalum, niobium, gallium, germanium, and mixtures thereof.

9. The process as claimed in claim 1 , wherein the catalyst has a water extractable quantity of potassium in the range of from 1.25 to 10 mmole/kg, relative to the weight of the catalyst.

10. The process as claimed in claim 1 , wherein the catalyst further comprises deposited on the carrier a potassium promoter in a quantity of at least 0.5 mmole/kg, relative to the weight of the catalyst.

11. The process as claimed in claim 1 , wherein the rhenium promoter is present in a quantity in the range of from 0.1 to 50 mmole/kg, relative to the weight of the catalyst.

12. The process as claimed in claim 1 , wherein the molar ratio of the rhenium promoter to the second co-promoter is greater than 1.

13. The process as claimed in claim 1 , wherein the first co-promoter is present in a quantity in the range of from 0.2 to 50 mmole/kg, relative to the weight of the catalyst and the second co-promoter is present in a quantity in the range of from 0.1 to 40 mmole/kg, relative to the weight of the catalyst.

14. The process as claimed in claim 1 , wherein the molar ratio of the first co-promoter to the second co-promoter is greater than 1.

15. A process for preparing a 1,2-diol, a 1,2-diol ether, a 1,2-carbonate, or an alkanolamine comprising:

contacting a reactor feed comprising an olefin, oxygen, and carbon dioxide, with a catalyst so as to form an olefin oxide, wherein the catalyst comprises a carrier and, deposited on the carrier, silver, a rhenium promoter, a first co-promoter, and a second co-promoter,

wherein the carbon dioxide is present in the reactor feed in a quantity of at most 3 mole percent based on the total reactor feed;

wherein the first co-promoter is selected from the group consisting of sulfur, phosphorus, boron, and mixtures thereof; and

wherein the second co-promoter is selected from the group consisting of tungsten, molybdenum, chromium, and mixtures thereof; and

converting the olefin oxide into the 1,2-diol, the 1,2-diol ether, the 1,2-carbonate, or the alkanolamine.

16. The process as claimed in claim 15 , wherein the first co-promoter is sulfur and the second co-promoter is tungsten.

17. The process as claimed in claim 16 , wherein the molar ratio of the first co-promoter to the second co-promoter is in the range of from greater than 1 to 20.

18. The process as claimed in claim 1 , wherein the first co-promoter is sulfur and the second co-promoter is tungsten.

19. The process as claimed in claim 18 , wherein the molar ratio of the first co-promoter to the second co-promoter is in the range of from greater than 1 to 20.