The literature contains reports to various forms or structures of manganese oxide. One such structure is the hollandite structure which consists of octahedrally coordinated framework metal atoms and contains one-dimensional channels. To obtain charge neutrality, Group I or II metal cations or the ammonium cation are present in the channels. Stroebel and Charenton in Revue de Chem. Minerale, 23, 125 (1986) have reported on various structures of manganese oxide including hollandite structures with K.sup.+, Na.sup.+, Rb.sup.+, NH.sub.4.sup.+, Ba.sup.2+, and Pb.sup.2+ in the tunnels, layered manganese oxides or phyllomanganates containing Na.sup.+, K.sup.+, NH.sub.4.sup.+ and Cs.sup.+, psilomelane containing Na.sup.+ or Ba.sup.2+ and various Li manganates. These structures were prepared by oxidation of Mn.sup.2+, reduction of Mn.sup.7+, or transformation of .beta.-MnO.sub.2 under severe conditions. Giovanoli and Faller in Chimia, 43, 54 (1989) have reported the preparation of K.sup.+, Rb.sup.+, Cs.sup.+, Ca.sup.2+, Sr.sup.2+, Pb.sup.2+, or Na.sup.+ hollandites by hydrothermal synthesis at 500.degree. C. from .gamma.-MnOOH. Further, the synthesis of K.sup.+ manganese oxide hollandite via the hydrothermal conproportionation of Mn.sup.2+ and MnO.sub.4.sup.- at temperatures of about 100.degree. C. and pH of less than 2 has been reported by O'Young in Synthesis of Microporous Materiald, M. Ocelli and H. Robson eds., Von Nostrand Reinhold, N.Y., Vol 2, p. 333 (1992). Yin et al. in Inorg. Chem., 33, 4384 (1994) have prepared manganese oxide with the hollandite structure in which Ni.sup.2+, Ca.sup.2+ or Fe.sup.3+ are present in the tunnels. Hollandite manganese oxide with Li.sup.+ or H.sup.+ in the tunnels have been prepared. See Rossow et al., Mat. Re. Bull., 27, 221 (1992) and Tsuji et al., J. Mater. Res., 8, 3145 (1993). Post et al. in Acta Cryst., B38, 1056 (1982) have reported on the structures of minerals having the hollandite structure, including ((Ba.sub.0.75 Pb.sub.0.16 Na.sub.0.10 K.sub.0.04) (Mn,Fe,Al).sub.8 (O,OH).sub.16) and ((K.sub.0.94 Na.sub.0.25 Sr.sub.0.13 Ba.sub.0.10) (Mn,Fe,Al).sub.8 (O,OH).sub.16). Bystrom and Bystrom in Acta Cryst., 3, 146 (1950) have reported on manganese oxide minerals with the hollandite crystal structure. The materials contain manganese, iron, titanium and aluminum. Finally, Mukherjee in Acta Cryst., 13, 164 (1960) presents the space group and cell dimensions of a material having the formula BaFeMn.sub.7 O.sub.16.
Applicant has discovered a new class of compositions based on manganese oxide and at least one other metal oxide. These compositions have a three dimensional structure with manganese and at least one other metal, e.g., chromium, vanadium, gallium, antimony forming the framework. The metallo manganese oxides of this invention are capable of catalyzing hydrocarbon conversion reactions such as oxidation and oxidative dehydrogenation.