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ɛ-Keggin-based mixed metal oxide (ɛ-MoMO) comprises a network arrangement based on an ɛ-Keggin {Mo12O40} unit and a {MO6} octahedral, forming a framework structure containing cage and channel textures such as an Faujasite (FAU)-type zeolite. In this study, we successfully synthesized 3 novel ɛ-MoMOs, namely ɛ-MoMgO, ɛ-MoYO, and ɛ-MoInO, and their physicochemical properties were investigated. All these materials showed a microporosity to adsorb CO2of up to 33% to 42% in their crystallographically expected microporous capacity.Three novel ɛ-Keggin-based mixed metal oxides composed of an ɛ-Keggin unit {Mo12O40} and a {MO6} octahedral (M = In, Y, and Mg) were synthesized and their microporosities were investigated.

Surface base property of magnesium oxide can be modified by the addition of metal ion. The addition of metal ion with larger ionic radius than Mg2+causes the increase of the amount of surface base site, whereas the addition of metal ion with smaller ionic radius than Mg2+shows not to be effective.

Structural stability of scheelite catalysts, Bi1−x/3V1−xMoxO4, in the reduction and reoxidation cycle increases with an increase of the mobility of the lattice oxide ions in the catalysts.

Catalytic ammoxidation of propane to acrylonitrile proceeds selectively over multicomponent metal oxides containing both bismuth and molybdenum with scheelite related structures. Higher selectivity to acrylonitrile and higher space time yield are obtained at reaction temperatures higher than 500 °C and higher concentration of propane (>40%) in the feed gas.

The lithium and sodium salts of four distinct types of complex bismuth oxychlorides having different structural layer units within the Sillenite family of solids have been employed as catalysts for the selective oxidation of methane. The catalytic performance strongly depends on the environment of chloride ion in the structure; and it is likely that a radical mechanism operates.

Participation of the lattice oxide ions in various tellurium-based multicomponent oxide catalysts, Te–Mo–M–O (M = Co, Mn, Fe and Cu) was investigated using 18O2tracer in the selective oxidation of propylene to acrolein. High mobility of the lattice oxide ions in this system plays an important role in stabilizing the active site for the redox process and in suppressing the vaporization of tellurium metal from the catalyst during the reaction.

Promotion effect of trivalent metal ions in tetra-component bismuth molybdate catalysts, Mo10Bi1Co8M3IIIOxwas investigated using 18O2tracer in the selective oxidation of propylene to acrolein. MIII, especially Fe3+, introduces cation vacancies into CoMoO4in the form of Co1−3x2+M2xIIIφxMoO4which accelerate the bulk diffusion of the lattice oxide ions to increase the catalytic activity of the multicomponent systems.

Various mixed metal oxide catalysts were tested for the oxidation of propane to acrolein. An Ag-doped bismuth vanadomolybdate catalyst was found to be most effective among the catalysts tested; the selectivity to acrolein reached to more than 60% at 13% conversion of propane.

3-D ordered macroporous (3DOM) crystalline CsxH3−xPW12O40and (NH4)xH3−xPW12O40were synthesized by a colloidal crystal template method. CsxH3−xPW12O40and (NH4)xH3−xPW12O40were deposited in the voids of templates by a two-step impregnation process and homogeneous precipitation, respectively, and polymer templates were removed by subsequent calcination. 3DOM crystalline CsxH3−xPW12O40exhibits trimodal micro-, meso-, and macroporosity.

Carbon dioxide greatly enhanced the formation rate of acrylonitrile in the gas-phase reaction of acetonitrile with methanol over magnesium oxide catalyst. The reaction in the presence of carbon dioxide was accompanied by the reaction of methanol with carbon dioxide to give carbon monoxide and water. An adsorbed carbon dioxide species on the basic surface of magnesium oxide seems to afford an active methanol-derived species for the reaction with acetonitrile.

Solid-base catalyst, MgO modified by metal ion promoted the cross-coupling reaction between methylpropionate and methanol to give methylmethacrylate. 65% selectivity to methylmethacrylate was attained by using 16.7 wt% Mn–MgO catalyst at 400 °C.

An isotope exchange reaction of hydrogen in methyl group of methanol was found to occur over solid-base catalysts. A mixture of CD3OD and CH3OD (1:1), when passed over MgO at 330 °C, changed to a nearly isotopically equilibrated mixture of deuterated methanols.

1,1,1-Trichloro-2,2,2-trifluoroethane or 1,1-dichloro-1,2,2,2-tetrafluoroethane, both of which have CF3group, dimerizes over supported Ni catalysts at an elevated temperature (723 K) into corresponding C4-compounds in good to moderate yields.

Methyl vinyl ketone was obtained at 30–40% selectivity by the reaction of methanol and acetone at 350 °C over Ti(IV)-, Cr(III)-, Mn(II)-, and Sn(IV)-exchanged forms of fluoro tetrasilicic mica (TSM). The addition of oxygen into the feed increased the conversion of acetone and the reaction over Ti(IV)-TSM converted 11% of acetone fed into methyl vinyl ketone at 85% selectivity.

Mn(II), Co(II), Cu(II), or Fe(III) ion containing magnesium oxides catalyzed oxidation of 2,6-di-t-butylphenol to quinones by molecular oxygen. 98% Yield to 1,1′-bis(4-oxo-3,5-di-t-butylcyclohexadienylidene) was obtained with 16.7 wt% Mn ion containing magnesium oxide catalyst.

Methanol was converted into a variety of oxygenated compounds including esters, ketones, and aldehydes at 350 °C over Ti ion-based catalysts, for which Zn and Cl ions were effective additives.