Catalytic systems for the conversion of hydrocarbons to functionalized products
View Patent ↗This invention discloses methods and processes for selectively converting hydrocarbons such as methane to materials such as alcohols or other materials containing more reactive functionalities.
1. A process for selective oxidation of hydrocarbons, wherein selectivity is of an unreacted hydrocarbon and not an oxidized hydrocarbon, comprising
passing a feed comprising hydrocarbons and an oxidant to a first catalyst zone comprising an activated metal catalyst, at functionalization conditions, to form an effluent comprising selectively oxidized hydrocarbon product and reduced oxidant;
separating the selectively oxidized hydrocarbon product from the reduced oxidant;
passing the reduced oxidant and a reoxidizer to a reoxidation zone, at reoxidizing conditions, to reform the oxidant;
wherein the activated metal catalyst comprises a transition metal selected from the group consisting of Re, Os, Ir, Ru, W, and Rh, where the metal is coordinated to one or more oxidation resistant ligands, and wherein the functionalization conditions comprise a temperature of between 100 and 350 degrees C. and a solvent having an acidity level selected from the group consisting of neutral, basic, and highly basic, thereby producing a selectively oxidized hydrocarbon product.
2. The process of claim 1 wherein the feed comprises an alkane and the selectively oxidized hydrocarbon product comprises an alcohol.
3. The process of claim 2 wherein the feed comprises methane and the product selectively oxidized hydrocarbon comprises methanol.
4. The process of claim 1 , wherein said one or more oxidation resistant ligand is selected from the group consisting of hydroxy, alkoxy, oxo, carboxylate, optionally substituted diol, optionally substituted catechol, optionally substituted polyol, and optionally substituted acetylacetonate.
5. The process of claim 1 , wherein said one or more oxidation resistant ligand is selected from the group consisting of ammine, optionally substituted amine, optionally substituted amide, optionally substituted nitrogen heterocycle, optionally substituted chelating diamine, optionally substituted chelating polyamine, optionally substituted chelating amide, and optionally substituted linked nitrogen heterocycle.
6. The process of claim 1 wherein the first catalyst zone further comprises a solvent selected from the group consisting of amine and conjugate base amides, alcohol and conjugate base alkoxide, water-containing hydroxides, and a molten salt mixture.
7. The process of claim 1 wherein the functionalization conditions comprise a temperature of between 150 and 250 degrees C.
8. The process of claim 1 wherein the reoxidizer is oxygen.
9. The process of claim 1 wherein the reoxidizer is air.
10. The process of claim 1 wherein the activated metal catalyst is supported on a solid support.
11. The process of claim 1 wherein the oxidant is an O-atom donor.
12. The process of claim 11 wherein the O-atom donor is selected from the group consisting of cupric oxide (CuO), selenate, (SeO 4 2− ), vanadate (VO 4 3− ), and sulfoxide.
13. The process of claim 1 , wherein the solvent is neutral.
14. The process of claim 1 , wherein the solvent is basic.
15. The process of claim 1 , wherein the solvent is highly basic.
16. The process of claim 1 , wherein the solvent is selected from the group consisting of amine and conjugate base amides, alcohol and conjugate base alkoxide, water-containing hydroxides, and a molten salt mixture.
17. The process of claim 1 , wherein the feed comprises an arene.
18. The process of claim 17 , wherein the arene is benzene.
19. The process of claim 1 , wherein the process does not operate by the generation of free radicals.