Abstract: The present invention relates to a composite oxide comprising ceria, praseodymia and alumina, wherein the cerium:praseodymium molar ratio of the composite oxide is 84:16 or less, as well as to a method of preparing the composite oxide and to its use, in particular in a method of treating an exhaust gas stream.

Abstract: A compound of the general formula (I) AaMbPcOd??(I) in which the variables are each defined as follows: M is at least one transition metal selected from Co, Ni, Mn, Fe and Cr, A is Li or LixNa1-x where x is in the range from 0.2 to 1.0, a is in the range from 3.5 to 4.5, b is in the range from 0.8 to 1.2, c is in the range from 1.8 to 2.2 and d is in the range from 7.2 to 8.8.

Abstract: The invention relates to novel silver vanadium phosphates, catalysts based on these silver vanadium phosphates and the use of these catalysts for carrying out organic reactions in the gas phase.

Abstract: A compound of the general formula (I) AaMbPcOd??(I) in which the variables are each defined as follows: M is at least one transition metal selected from Co, Ni, Mn, Fe and Cr, A is Li or LixNa1-x where x is in the range from 0.2 to 1.0, a is in the range from 3.5 to 4.5, b is in the range from 0.8 to 1.2, c is in the range from 1.8 to 2.2 and d is in the range from 7.2 to 8.8.

Abstract: A novel polynary vanadyl pyrophosphate of the general formula I (VO)a(M1-bVb)2(P2O7)c is described, in which M is one or more metals selected from Ti, Zr, Hf, Cr, Fe, Co, Ni, Ru, Rh, Pd, Cu, Zn, B, Al, Ga and In, a is from 0.5 to 1.5, b is from 0 to 0.9, c is from 1.5 to 2.5, having a crystal structure whose powder X-ray diffractogram is characterized by defined reflections. A preferred representative is (VO)Fe2(P2O7)2. The vanadyl pyrophosphates are suitable as gas phase oxidation catalysts, for example for preparing maleic anhydride from a hydrocarbon having at least four carbon atoms.

Abstract: A novel polynary metal oxide phosphate of the general formula I MaV4-aOb(PO4)c is described, in which M is one or more metals selected from Ti, Zr, Hf, Cr, Fe, Co, Ni, Ru, Rh, Pd, Cu, Zn, B, Al, Ga and In, a is from 0 to 2.0, b is from 2.0 to 4.0, c is from 2.0 to 4.0, having a crystal structure whose powder X-ray diffractogram is characterized by defined reflections. Preferred representatives are V4O3(PO4)3, CrV3O3(PO4)3, FeV3O3(PO4)3 and TiV3O3(PO4)3. The metal oxide phosphates are suitable as gas phase oxidation catalysts, for example for preparing maleic anhydride from a hydrocarbon having at least four carbon atoms.

Abstract: A novel polynary metal oxide phosphate of the general formula I MaV2Ob(PO4)c is described, in which M is one or more metals selected from V, Cr, Fe, Co, Ni, Ru, Rh, Pd, Cu, Zn, Cd, Hg, Be, Mg, Ca, Sr and Ba, a is from 0.5 to 1.5, b is from 1.5 to 2.5, c is from 1.5 to 2.5, having a crystal structure whose powder X-ray diffractogram is characterized by defined reflections. Preferred representatives are CoV2O2(PO4)2, NiV2O2(PO4)2 or CuV2O2(PO4)2. The metal oxide phosphates are suitable as gas phase oxidation catalysts, for example for preparing maleic anhydride from a hydrocarbon having at least four carbon atoms.

Abstract: A novel polynary metal oxide phosphate of the general formula I Ma(VO)(P2O7)b(PO4)c is described, in which M is one or more metals selected from V, Ti, Zr, Hf, Cr, Fe, Co, Ni, Ru, Rh, Pd, Cu, Zn, Cd, Hg, B, Be, Mg, Ca, Sr and Ba, a is from 1.5 to 2.5, b is from 0.5 to 1.5, c is from 0.5 to 1.5, having a crystal structure whose powder X-ray diffractogram is characterized by defined reflections. A preferred representative is Fe2VO(P2O7)(PO4). The metal oxide phosphates are suitable as gas phase oxidation catalysts, for example for preparing maleic anhydride from a hydrocarbon having at least four carbon atoms.