Catalysts for petrochemical catalysis

Abstract

Metal oxide catalysts comprising various dopants are provided. The catalysts are useful as heterogeneous catalysts in a variety of catalytic reactions, for example, the oxidative coupling of methane to C2 hydrocarbons such as ethane and ethylene. Related methods for use and manufacture of the same are also disclosed.

1 . A catalyst having the following formula:
   A x B y O z ;   wherein:   A is an element from the lanthanides or group 2, 3, 4, 6 or 13;   B is an element from groups 4, 12 or 13 of the periodic table or Ce, Pr, Nd, Sm, Eu, Gd, Tb or Ho;   O is an oxygen anion; and   x, y and z are each independently numbers greater than 0,   the catalyst further comprising one or more dopants from any one of groups 2, 3 or the lanthanides, and provided that A and B are not the same, wherein the catalyst comprises a methane conversion of greater than 20% and a C2 selectivity of greater than 50% when the catalyst is employed as a heterogeneous catalyst in the oxidative coupling of methane at temperatures ranging from about 550° C. to about 750° C.   
     
     
         2 . The catalyst of  claim 1 , wherein A is Ba, Zr, Sr, Sm, Hf, Gd, Er, Y, Ca, La, Mg, W, B, Tb or Ce. 
     
     
         3 . The catalyst of  claim 1 , wherein B is Zn, Hf, Zr, Al, Ti, Pr, Nd, Ce, Sm, Eu, Gd, Tb or Ho. 
     
     
         4 . The catalyst of  claim 1 , wherein A is from group 2, and B is from group 4. 
     
     
         5 . The catalyst of  claim 1 , wherein A is Ba, Sr or Ca. 
     
     
         6 . The catalyst of  claim 1 , wherein B is Ti, Zr or Hf. 
     
     
         7 . The catalyst of  claim 1 , wherein the catalyst has the formula ABO 3 . 
     
     
         8 . The catalyst of  claim 1 , wherein the catalyst comprises one or more dopant from group 2. 
     
     
         9 . The catalyst of  claim 1 , wherein the catalyst comprises one or more dopant from group 3. 
     
     
         10 . The catalyst of  claim 1 , wherein the catalyst comprises one or more dopant from the lanthanides. 
     
     
         11 . The catalyst of  claim 1 , wherein the dopant is Sr, Y, La, Nd, Ca, Mg or Ce or a combinations thereof. 
     
     
         12 . The catalyst of  claim 1 , wherein the catalyst comprises BaZrO 3 , SrZrO 3 , SrAlO 3 , SrCeO 3 , SrHfO 3 , CaHfO 3 , SrTbO 3  or BaTiO 3 . 
     
     
         13 . The catalyst of  claim 1 , wherein the catalyst is a bulk catalyst. 
     
     
         14 . The catalyst of  claim 1 , wherein the catalyst is a nanostructured catalyst. 
     
     
         15 . The catalyst of  claim 14 , wherein the catalyst is a nanowire. 
     
     
         16 . The catalyst of  claim 1 , wherein the catalyst further comprises a support or carrier. 
     
     
         17 . The catalyst of  claim 16 , wherein the support or carrier comprises silicon, magnesium, yttrium, zirconium, lanthanum, hafnium, aluminum or gallium. 
     
     
         18 . The catalyst of  claim 17 , wherein the support or carrier comprises SiO 2 , MgO, Y 2 O 3 , ZrO 2 , La 2 O 3 , HfO 2 , InO 2 , Al 2 O 30 r Ga 2 O 3 . 
     
     
         19 . The catalyst of  claim 1 , wherein the catalyst is in the form of a formed aggregate. 
     
     
         20 . A catalyst comprising one of the following formulas:
   E 1   a A x B y O z ;  i)
     E 1   a E 2   b A x B y O z ; or  ii)
     E 1   a E 2   b E 3   c A x B y O z ,  iii)
   wherein:   A is Ba, Zr, Sr, Sm, Hf, Gd, Er, Y, Ca, La, Mg, W, B, Tb or Ce;   B is Zn, Hf, Zr, Al, Ti, Pr, Nd, Ce, Sm, Eu, Gd, Tb or Ho;   E1, E 2  and E 3  are each independently an element from groups 2, 3, 4 or the lanthanides;   O is oxygen; and   a, b, c, x, y and z are each independently numbers greater than 0, wherein the catalyst further comprises a methane conversion of greater than 20% and a C2 selectivity of greater than 50% when the catalyst is employed as a heterogeneous catalyst in the oxidative coupling of methane at a temperatures ranging from about 550° C. to about 750° C., and provided that A and B are not the same.   
     
     
         21 . The catalyst of  claim 20 , wherein the catalyst comprises La 0.8 Sr 0.2 Ga 0.9 Mg 0.1 O 3 .