Methane conversion process

Abstract

In an improved method for converting methane to at least one higher hydrocarbon product and coproduct water which comprises contacting a gas comprising methane and at least one added gaseous oxidant with nonacidic solid, the improvement comprising conducting at least a portion of said contacting in the presence of added water.

What is claimed: 
     
       1. In a method for converting methane to higher hydrocarbons wherein a gas comprising methane and a gaseous oxidant are contacted with a nonacidic solid .Iadd.which is substantially nonreducible under the contacting conditions .Iaddend.to produce higher hydrocarbons and coproduct water, the improvement which comprises conducting at least a portion of said contacting in the presence of added water. . .2. The method of claim 1 wherein said solid comprises at least one reducible metal oxide of at 
     
     
        least one metal..!.3. The method of claim 1 wherein the mole ratio of said 
     
     
        added water to said methane in said gas is less than about 10. 4. The method of claim 1 wherein the mole ratio of said added water to said 
     
     
        methane in said gas is in the range of about 0.01 to about 6. 5. The method of claim 1 wherein the mole ratio of said added water to said 
     
     
        methane in said gas is in the range of about 0.05 to about 4.0. 6. The method of claim 1 wherein the contacting is conducted at a temperature 
     
     
        within the range of about 300° to about 1200° C. 7. The method of claim wherein the contacting is conducted at a temperature of 
     
     
        about 700° to about 1200° C. 8. The method of claim 1 wherein the contacting is conducted at a temperature of about 800° 
     
     
        to about 1000° C. 9. The method of claim 3 wherein the contacting is conducted at a temperature of about 500° to about 1000° 
     
     
        C. 10. The method of claim 1 wherein said solid is selected from the group 
     
     
        consisting of basic metal oxides. 11. The method of claim 10 wherein said solid is selected from the group consisting of alkaline earth oxides and 
     
     
        mixtures thereof. 12. The method of claim 10 wherein said solid comprises 
     
     
        magnesia. 13. The method of claim 10 wherein said solid comprises CaO. 
     
     
            The method of claim . .10.!. .Iadd.1 .Iaddend.wherein said solid 
     
     
        comprises titania. 15. The method of claim . .10.!. .Iadd.1 
     
     
        .Iaddend.wherein said solid comprises silica. 16. The method of claim 10 wherein said solid comprises barium. . .17. The method of claim 2 wherein said solid is substantially nonreducible under the contacting 
     
     
        conditions..!.18. The method of claim . .11.!. .Iadd.1 .Iaddend.wherein said solid . .further.!. comprises .Iadd.an alkaline earth oxide together 
     
     
        with .Iaddend.at least one alkali metal component. 19. The method of claim 18 wherein the alkali metal component is selected from the group 
     
     
        consisting of sodium and compounds thereof. 20. The method of claim 18 wherein the alkali metal component is selected from the group consisting 
     
     
        of lithium and compounds thereof. 21. The method of claim 18 whereto the alkali metal component is selected from the group consisting of potassium 
     
     
        and compounds thereof. 22. The method of claim 1 wherein the gaseous 
     
     
        oxidant comprises molecular oxygen. 23. The method of claim 1 wherein the 
     
     
        gaseous oxidant comprises oxides of nitrogen. 24. The method of claim 23 
     
     
        wherein the oxides of nitrogen comprises N 2  O. . .25.  In a method for converting methane into higher hydrocarbon products and coproduct water which comprises contacting a gas comprising methane and an oxygen-containing gas with a solid comprising at least one reducible metal oxide of at least one metal, which oxide when contacted with methane at 500° to 1000° C. produces higher hydrocarbons, coproduct water, and reduced metal oxide, the improvement comprising conducting at least a portion of the contacting in the presence of added water..!.. .26. The method of claim 25 wherein the mole ratio of said added water to said methane in said gas is less than about 10..!.. .27. The method of claim 25 wherein the mole ratio of said added water to said methane in said gas is in the range of about 0.01 to about 6..!.. .28. The method of claim 25 wherein the mole ratio of said added water to said methane in said gas is in the range of about 0.05 to about 4.0..!.. .29. The method of claim 25 wherein the solid comprises at least on reducible oxide of Mn..!.. .30. The method of claim 29 wherein the solid comprises at least one member of the group consisting of alkali metals, alkaline earth metals, and 
     
     
        compounds and mixtures thereof..!.. .31.  The method of claim 29 wherein the solid comprises at least one member of the group consisting of boron and compounds thereof..!.. .32. The method of claim 30 wherein the solid comprises at least one member of the group consisting of boron and compounds thereof..!..Iadd.33. A method for the oxidative conversion of methane to higher hydrocarbons and coproduct water, comprising: contacting said methane, a free oxygen-containing gas and water with at least one solid contact material which is substantially nonreducible under the contacting conditions selected from the group consisting of a solid contact material consisting essentially of lanthanum oxide and solid contact materials comprising (a) at least one promoter comprising an alkali metal and (b) at least one base material selected from the group consisting of magnesium oxide and calcium oxide, under oxidative conversion conditions sufficient to convert said methane to said higher hydrocarbons. .Iaddend..Iadd.34. A process in accordance with claim 33, wherein said solid contact material consists essentially of at least one lithium-containing promoter and magnesium oxide as base material. .Iaddend.