(FR2721598-A1)      The prepn. of a mixed oxide comprising V, Sb and Sn of the general formula:- VSbaSnbOx -a = 0.1 or more (whole or fractional numbers) -b = 0.5 or more (whole or fractional numbers). -x = whole or fractional number determined by degree of oxidn. of other elements. The mixed oxide has an X ray diffraction pattern consistent with a crystallographic phase of SnO2 rutile structure. The cpd. is prepared in the following stages:- cpds. of V, Sb and Sb are dissolved in at least one satd. alcohol. -the alcoholic soln .obtd. is contacted with an aq. soln. contg. an ammonium salt, to precipitate the mixed oxide. -the oxide is separated and calcined. Also claimed is a process of ammoxidation of 8-12C alkanes, using the prepared catalyst.    USE -   The ammoxidation process is partic. useful in the oxidn. of propane (to give propylene and acrylonitrile) and isobutane (giving methacrylonitrile and isobutene or n-butenes).    ADVANTAGE -   The invention gives mixed oxides with improvedcatalytic properties compared with those obtd. by previous processes.    (JP8000996-A)      Prodn. of an ammoxidation catalyst which is a mixed oxide represented by VSbaSnbOx (wherein a is 0.1-100 pref. 0.5 - 50, b = 0.5 - 50, b = 0.5 - 100 pref. 1 - 40, x is a number to be decided by the oxidn. condition of other elements), which shows x-ray diffraction line characteristics that are similar to those of rutile SnO2 type crystalline phase, wherein a vanadium cpd, an antimony cpd. of a thin cpd. are dissolved in at least one kind of satd. alcohol, and the resulting alcohol soln. is contacted with an aq. soln. contg. an ammonium salt to pptd. a mixed oxide, which is then sepd. and burned. The satd. alcohol is pref. alkanol or cycloalkanol pref. alkanol having 1 - 6 C atoms or cyclohexanol.    USE -   The produced catalyst is useful for ammoxidation of alkanes.    (EP691306-B1)      The prepn. of a mixed oxide comprising V, Sb and Sn of the general formula:- VSbaSnbOx -a = 0.1 or more (whole or fractional numbers) -b = 0.5 or more (whole or fractional numbers). -x = whole or fractional number determined by degree of oxidn. of other elements. The mixed oxide has an X ray diffraction pattern consistent with a crystallographic phase of SnO2 rutile structure. The cpd. is prepared in the following stages:- cpds. of V, Sb and Sb are dissolved in at least one satd. alcohol. -the alcoholic soln .obtd. is contacted with an aq. soln. contg. an ammonium salt, to precipitate the mixed oxide. -the oxide is separated and calcined. Also claimed is a process of ammoxidation of 8-12C alkanes, using the prepared catalyst.    USE -   The ammoxidation process is partic. useful in the oxidn. of propane (to give propylene and acrylonitrile) and isobutane (giving methacrylonitrile and isobutene or n-butenes).    ADVANTAGE -   The invention gives mixed oxides with improvedcatalytic properties compared with those obtd. by previous processes.    (JP2811424-B2)      The prepn. of a mixed oxide comprising V, Sb and Sn of the general formula:- VSbaSnbOx -a = 0.1 or more (whole or fractional numbers) -b = 0.5 or more (whole or fractional numbers). -x = whole or fractional number determined by degree of oxidn. of other elements. The mixed oxide has an X ray diffraction pattern consistent with a crystallographic phase of SnO2 rutile structure. The cpd. is prepared in the following stages:- cpds. of V, Sb and Sb are dissolved in at least one satd. alcohol. -the alcoholic soln .obtd. is contacted with an aq. soln. contg. an ammonium salt, to precipitate the mixed oxide. -the oxide is separated and calcined. Also claimed is a process of ammoxidation of 8-12C alkanes, using the prepared catalyst.    USE -   The ammoxidation process is partic. useful in the oxidn. of propane (to give propylene and acrylonitrile) and isobutane (giving methacrylonitrile and isobutene or n-butenes).    ADVANTAGE -   The invention gives mixed oxides with improvedcatalytic properties compared with those obtd. by previous processes.