CATALYSTS FOR PETROCHEMICAL CATALYSIS
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 - 85 . (canceled)
86 . A catalyst comprising 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 dopant from any one of groups 2, 3 or the lanthanides, and 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.
87 . The catalyst of claim 86 , wherein A is Ba, Zr, Sr, Sm, Hf, Gd, Er, Y, Ca, La, Mg, W, B, Tb or Ce.
88 . The catalyst of claim 86 , wherein B is Zn, Hf, Zr, Al, Ti, Pr, Nd, Ce, Sm, Eu, Gd, Tb or Ho.
89 . The catalyst of claim 86 , wherein A is from group 2, and B is from group 4.
90 . The catalyst of claim 86 , wherein A is Ba, Sr or Ca.
91 . The catalyst of claim 86 , wherein B is Ti, Zr or Hf.
92 . The catalyst of claim 86 , having the formula ABO 3 .
93 . The catalyst of claim 86 , comprising one or more dopant from group 2.
94 . The catalyst of claim 86 , comprising one or more dopant from group 3.
95 . The catalyst of claim 86 , comprising one or more dopant from the lanthanides.
96 . The catalyst of claim 86 , wherein the dopant is Sr, Y, La, Nd, Ca, Mg or Ce or a combinations thereof.
97 . The catalyst of claim 86 , comprising the formula BaZrO 3 , SrZrO 3 , SrAlO 3 , SrCeO 3 , SrHfO 3 , CaHfO 3 , SrTbO 3 or BaTiO 3 .
98 . The catalyst of claim 86 , wherein the catalyst is a bulk catalyst.
99 . The catalyst of claim 86 , wherein the catalyst is a nanostructured catalyst.
100 . The catalyst of claim 99 , wherein the catalyst is a nanowire.
101 . A catalytic material comprising the catalyst of claim 86 in combination with a support or carrier.
102 . The catalytic material of claim 101 , in the form of a formed aggregate.
103 . A method for the oxidative coupling of methane, the method comprising contacting methane with the catalytic material of claim 101 , at temperatures ranging from about 550° C. to about 750° C., wherein the method comprises a methane conversion of greater than 20% and a C2 selectivity of greater than 50%.
104 . A catalyst comprising one of the following formulas:
i) E 1 a A x B y O z ;
ii) E 1 a E 2 b A x B y O z ; or
iii) E 1 a E 2 b E 3 c A x B y O z ,
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;
E 1 , 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.
105 . The catalyst of claim 104 , wherein A is from group 2, and B is from group 4.
106 . The catalyst of claim 104 , wherein A is Ba, Sr or Ca.
107 . The catalyst of claim 104 , wherein B is Ti, Zr or Hf.
108 . The catalyst of claim 104 , wherein E 1 , E 2 and E 3 are each independently selected from Sr, Y, La, Nd, Ca, Mg and Ce.
109 . The catalyst of claim 104 , wherein the catalyst comprises one of the following formulas: Y/SrZrO 3 , SrHfO 3 , SrZrO 3 , Mg/SrHfO 3 , Sr/Gd 2 O 3 , CaHfO 3 , SrTbO 3 , Sr/BaZrO 3 , Y/SrZrO 3 , La/SrAlO 3 , La/Nd/SrAlO 3 , Ca/BaZrO 3 , La/SrCeO 3 , SrZrO 3 , SrHfO 3 , Mg/SrHfO 3 , CaHfO 3 , SrTbO 3 , BaTiO 3 or Ce/GaPrO 3 .
110 . The catalyst of claim 104 , wherein the catalyst is a bulk catalyst.
111 . The catalyst of claim 104 , wherein the catalyst is a nanostructured catalyst.
112 . The catalyst of claim 111 , wherein the catalyst is a nanowire.
113 . A catalytic material comprising the catalyst of claim 104 in combination with a support or carrier.
114 . The catalytic material of claim 113 , in the form of a formed aggregate.
115 . A method for the oxidative coupling of methane, the method comprising contacting methane with the catalytic material of claim 113 , at temperatures ranging from about 550° C. to about 750° C., wherein the method comprises a methane conversion of greater than 20% and a C2 selectivity of greater than 50%.