Refractory mixed-metal oxides and spinel compositions for thermo-catalytic conversion of biomass

1. A process for catalytic thermolysis of cellulosic biomass, the process comprising heating the cellulosic biomass to a conversion temperature in presence of a catalyst system, wherein the catalyst system comprises a mixed metal oxide represented by the formula (X 1 O).(X 2 O) a .(X 3 Y b O 4 ) wherein X 1 , X 2 and X 3 are alkaline earth elements selected from the group consisting of Mg, Ca, Be, Ba , and mixture thereof, and Y is a metal selected from the group consisting of Al, Mn, Fe, Co, Ni, Cr, Ga, B, La, P, Ti, Zn and mixture thereof, wherein a is 0 or 1 and b is 0 1or 2.

2. The process of claim 1 wherein the heating step is performed in presence of hydrogen.

3. The process of claim 1 wherein the heating step is performed in presence of steam.

4. The process of claim 1 wherein the thermolysis is performed in presence of recycled gaseous products.

5. The process of claim 1 wherein X 1 , X 2 and X 3 represent the same element.

6. The process of claim 1 wherein X 1 is a different element than X 2 and X 3 .

7. The process of claim 1 wherein the catalyst system comprises mixed metal oxides represented by the formula CaO.MgO.(MgAl 2 O 4 ).

8. The process of claim 1 wherein the alkaline earth elements X 1 , X 2 and X 3 are selected from the group consisting of Ca and Mg and the metal element Y is Al.

9. The process of claim 1 , wherein the catalyst system comprises spinels.

10. The process of claim 9 wherein the spinels have an alkaline earth element to a metal element molar ratio between 1:1 and 10:1.

11. The process of claim 9 wherein the spinels have a X-ray diffraction peaks at a 2- θ angle ranging between 35 ° to 68°.

12. The process of claim 1 wherein the catalyst system comprises transition aluminum.

13. The process of claim 1 wherein the catalyst system acts as a catalyst and as a heat carrier.

14. The process of claim 1 further comprising adding a heat carrier to the cellulosic biomass.

15. The process of claim 1 wherein the cellulosic biomass is contacted with the catalyst system in a pretreatment step.

16. The process of claim 15 wherein the pretreatment step comprises forming a biomass-catalysts system mixture and treating the mixture by thermal treatment, hydro-thermal treatment, torrefaction, mechanical treatment, swelling, steam explosion, precipitation, or combinations of any two or more of the foregoing.

17. The process of claim 16 wherein the step of treating the mixture is performed at an elevated temperature.

18. The process of claim 16 wherein the step of treating the mixture is performed at an elevated pressure.

19. The process of claim 16 wherein the mechanical treatment comprises milling, grinding, kneading or combinations of any two or more of the foregoing.

20. The process of claim 19 wherein the mechanical treatment is performed at an elevated temperature.

21. The process of claim 19 wherein the mechanical treatment is performed at an elevated pressure.

22. A process for catalytic hydropyrolysis of cellulosic biomass, the process comprising heating the cellulosic biomass to a conversion temperature in the presence of hydrogen, and in the presence of a catalyst system wherein the catalyst system comprises a mixed metal oxide represented by the formula (X 1 O).(X 2 O) a .(X 3 Y b O 4 ) wherein X 1 , X 2 and X 3 are alkaline earth elements selected from the group consisting of Mg, Ca, Be, Ba , and mixture thereof, and Y is a metal selected from the group consisting of Al, Mn, Fe, Co, Ni, Cr, Ga, B, La, P, Ti, Zn and mixture thereof, wherein a is 0 or 1 and b is 0, 1 or 2.

23. The process of claim 22 wherein the heating step is performed in the presence of an inert atmosphere.

24. The process of claim 23 wherein the heating step is performed in the presence of nitrogen.

25. The process of claim 22 wherein the heating step is performed in the presence of recycled gaseous products.

26. The process of claim 23 wherein the heating step is performed in the presence of carbon monoxide or carbon dioxide.