Preparation of catalyst and use for high yield conversion of methane to ethylene

1. A method of producing a perovskite catalyst comprising:

forming an aqueous slurry comprising an alkaline earth metal salt, a powdered metal salt and a powdered transition metal oxide; and

adding a polymeric binder to the slurry to form a paste;

drying the paste for forming a powder;

heating the powder at increasing temperatures at a predetermined profile commensurate with the polymeric binder; and

calcining the heated powder to form the perovskite catalyst.

2. the method of claim 1 , wherein the aqueous slurry is formed by:

dispersing a powdered alkaline earth metal salt in water,

adding the powdered metal salt to the water; and

adding the powdered transition metal oxide to the water.

3. The method of claim 2 wherein the alkaline earth metal salt is selected from the group consisting of barium, calcium and strontium salts.

4. The method of claim 2 wherein the metal oxide is titanium oxide.

5. The method of claim 3 , wherein the slurry comprises a mixture including Ba (0.5x-1x)+TiO2, wherein x is in moles.

6. The method of claim 3 , wherein the slurry comprises a mixture including Ba (0.5x -1x)+TiO2 and either Ca x or Sr x , wherein x is in moles.

7. The method of claim 5 , wherein the slurry is formed by a mixture according to Ba (0.5-0.95x)+TiO2+R(0.05-0.5x), wherein x is in moles, and wherein R is selected from the group consisting of BaCl 2 , LiCl, MgCl 2 , NaCl, and SnCl 2 .

8. The method of claim 7 , wherein the slurry comprises a mixture including Ba (0.5x-0.95x)+TiO 2 +SnCl 2 (0.05x), wherein x is in moles.

9. The method of claim 8 , wherein the slurry is formed by a mixture according to Ba (0.95x)+TiO 2 +SnCl 2 (0.05x), wherein x is in moles.

10. The method of claim 3 , wherein the polymeric binder is selected from the group of polymer binders consisting of vinyl acetate dibutyl acrylate and methyl hydroxyl ethyl cellulose.

11. The method of claim 10 , further comprising sizing the catalyst to a size suitable for a catalytic reactor.

12. The method of claim 11 , wherein the powder is heated by raising the temperature of the powder in a temperature profile comprising a series of successive ramping and holding stages up to the calcining temperature.

13. The method of claim 12 , wherein the temperature is raised to the calcining temperature at an increasing rate ranging from about 200° to about 400° C. per hour.

14. The method of claim 12 , wherein the temperature profile further comprises:

ramping the temperature from ambient to about 200° C. for about ¼ hour and holding for a hold period;

ramping the temperature to about 400° C. over about a further ¼ hour and holding for a hold period;

ramping the temperature to about 600° C. over about a further ¼ hour and holding for a hold period;

ramping the temperature to the calcination temperature over about a further ¼ hour and holding for ranging from about 8 hours to about 24 hours.

15. The method of claim 14 , wherein each hold period ranges from about ¼ hour to about 1 hour.

16. The method of claim 15 , wherein the hold period is about ¼ hour.

17. The method of claim 14 , wherein the calcining temperature is between about 700° C. to about 1000° C.

18. The method of claim 17 , wherein the calcining temperature is held for between about 8 hours to about 12 hours.

19. The method of claim 12 , further comprising:

ramping the temperature from ambient to about 100° C. for about ¼ hour and holding for about a further ¼ hour;

ramping the temperature to about 200° C. over about a further ¼ hour and holding the temperature for about a further ¼ hour;

ramping the temperature to the calcining temperature over about a further ¼ hour; and

holding the temperature at the calcining temperature for over about 8 hours.

20. The method of claim 19 , wherein the calcining temperature is between about 800° C. to about 1000° C.

21. The method of claim 20 , wherein the calcining temperature is held for between about 8 hours to about 12 hours.