Multimetal oxide compositions comprising Mo, Bi, Fe and Cu
Multimetal oxide composition comprising Mo, Bi, Fe, Cu and one or more than one of the elements Co and Ni and use thereof.
1. A multimetal oxide composition, comprising Mo, Bi, Fe and Cu and not comprising P, the multimetal oxide composition having the general stoichiometry (I):
Mo 12 Bi a Fe b Cu c Co d Ni e W f G g H h L l M m O x (I),
wherein:
G=at least one element selected from the group consisting of K, Na, Rb and Cs,
H=at least one element selected from the group consisting of Ba, Ca, Cr, Ce, La, Mg, Mn, Pb, Sn, Sr and Zn,
L=at least one element selected from the group consisting of B, Nb, Sb, Ta, Te, Ti, Y and Zr,
M=at least one element selected from the group consisting of Al and Si,
a=0.2 to 2.5,
b=0.5 to 4,
c=0.05 to 0.55,
d+e=4 to 11,
f=0 to 1.2,
g=0.03 to 0.5,
h=0 to 20,
l=0 to 10,
m=0 to 800,
x=a number which is determined by the valency and frequency of the elements in I other than oxygen,
12/( d+e+ 1.5* b+h )=0.8 to 2, and
a*c= 0.01 to 1.5.
2. The multimetal oxide composition according to claim 1 , wherein c=0.05 to 0.5.
3. The multimetal oxide composition according to claim 1 , wherein c=0.05 to 0.45.
4. The multimetal oxide composition according to claim 1 , wherein c=0.05 to 0.4.
5. The multimetal oxide composition according to claim 1 , wherein c=0.05 to 0.35.
6. The multimetal oxide composition according to claim 1 , wherein c=0.1 to 0.3.
7. An eggshell catalyst, comprising a shaped support body and an eggshell of at least one multimetal oxide composition according to claim 1 present on an outer surface of the shaped support body.
8. A shaped unsupported catalyst body, the active composition of which is at least one multimetal oxide composition according to claim 1 .
9. The unsupported catalyst according to claim 8 , having the geometry of a ring having a wall thickness of 1 to 3 mm, a length of 2 to 10 mm and an external diameter of 2 to 10 mm.
10. A process for producing the multimetal oxide composition according to claim 1 , the process comprising:
producing a finely divided intimate dry mixture from sources of the elemental constituents thereof and
calcining the finely divided intimate dry mixture at temperatures in the range from 350° C. to 650° C.
11. A process for heterogeneously catalyzed partial gas phase oxidation of an alkane, alkanol, alkanal, alkene and/or alkenal having 3 to 6 carbon atoms over a catalyst bed, the process comprising contacting the alkane, alkanal, alkene and/or alkenal having 3 to 6 carbon atoms with the catalyst bed,
wherein the catalyst bed comprises either:
at least one multimetal oxide composition according to claim 1 ,
at least one eggshell catalyst comprising a shaped support body and an eggshell of the at least one multimetal oxide composition present on an outer surface of the shaped support body,
at least one shaped unsupported catalyst body, the active composition of which is the at least one multimetal oxide composition, at least one shaped unsupported catalyst body having the geometry of a ring having a wall thickness of 1 to 3 mm, a length of 2 to 10 mm and an external diameter of 2 to 10 mm, and the active composition of which is the at least one multimetal oxide composition, or
the product of a process comprising producing a finely divided intimate dry mixture from sources of the elemental constituents thereof and calcining the finely divided intimate dry mixture at temperatures in the range from 350° C. to 650° C.
12. The process according to claim 11 , which is a process for heterogeneously catalyzed partial gas phase oxidation of propene to acrolein.
13. The multimetal oxide composition according to claim 1 , wherein m=0.1 to 500.
14. The multimetal oxide composition according to claim 1 , wherein W is present.
15. The multimetal oxide composition according to claim 1 , wherein at least one selected from the group of Cr, Ce, La, Mn, Pb, Sn, and Zn is present.