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Kozo Tanabe

Bio: Kozo Tanabe is an academic researcher from Hokkaido University. The author has contributed to research in topics: Catalysis & Isomerization. The author has an hindex of 43, co-authored 266 publications receiving 8700 citations.


Papers
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TL;DR: A statistical survey of industrial processes using solid acid-base catalysts is presented in this paper, where the number of processes such as alkylation, isomerization, amination, cracking, etherification, etc.
Abstract: A statistical survey of industrial processes using solid acid–base catalysts is presented. The number of processes such as alkylation, isomerization, amination, cracking, etherification, etc., and the catalysts such as zeolites, oxides, complex oxides, phosphates, ion-exchange resins, clays, etc., are 127 and 180, respectively. The classification of the types of catalysts into solid acid, solid base, and solid acid–base bifunctional catalysts gives the numbers as 103, 10 and 14, respectively. Some significant examples are described more in detail. On the basis of the survey, the future trend of solid acid–base catalysis and the fundamental research promising for industrial success are discussed.

972 citations

Book
Kozo Tanabe1
01 Jan 1970

629 citations

Journal ArticleDOI
Kozo Tanabe1
TL;DR: In this article, the surface properties of binary oxides containing zirconium oxide are characterized and the generation of super acidity on the addition of a small amount of sulfate ion to ZO is elucidated.
Abstract: Zirconium oxide is characterized to be the only one metal oxide which possesses explicitly four chemical properties on the surface; acidic and basic properties and oxidizing and reducing properties. Intriguing and sometimes unique catalytic activities of zirconium oxide itself are discussed in connection with the surface properties. It is also pointed out that zirconium oxide is an interesting and useful catalyst support. Generation of super acidity on the addition of a small amount of sulfate ion to zirconium oxide is elucidated. The surface properties of binary oxides containing zirconium oxide are also characterized.

348 citations

Journal ArticleDOI
TL;DR: The effect of sulfur promotion on the generation of strong acidity on ZrO/sub 2, TiO/Sub 2, Fe/sub O/sub 3, Al/sub S 2 O/S 3, SnO/S 2, and Bi O/O/3 was examined by the isomerization of cyclopropane and by infrared spectroscopy as discussed by the authors.
Abstract: The effect of sulfur promotion on the generation of strong acidity on ZrO/sub 2/, TiO/sub 2/, Fe/sub 2/O/sub 3/, Al/sub 2/O/sub 3/, SnO/sub 2/, SiO/sub 2/, and Bi/sub 2/O/sub 3/ was examined by the isomerization of cyclopropane and by infrared spectroscopy. The acidity generated varied on the types of oxides. The highest promotion effect was found in the cases of ZrO/sub 2/, TiO/sub 2/, and Fe/sub 2/O/sub 3/, while a lower effect was observed for Al/sub 2/O/sub 3/ and SnO/sub 2/, and no effect was found for SiO/sub 2/ and Bi/sub 2/O/sub 3/. Infrared spectroscopic observation indicates the presence of the surface sulfur complex having covalent SO double bonds on all of the sulfur-promoted oxides. An admission of pyridine resulted in a remarkable shift in an asymmetric stretching frequency of S=O bonds in the cases of ZrO/sub 2/, TiO/sub 2/, and Fe/sub 2/O/sub 3/; however, a small shift was found on Al/sub 2/O/sub 3/, and no shift was found on SiO/sub 2/ and Bi/sub 2/O/sub 3/. The magnitude of this shift was well-correlated with the extent of the promotion effect. The drastic shift suggests that a change of electronic structure in the surface sulfur complex takes place by the adsorptionmore » of basic molecules. The origin of the generation of the strong acidity by a sulfur promotion is the formation of the surface sulfur complex which has a covalent SO double bond on one hand and a strong tendency of losing its double-bond character or decreasing the bond order of SO by an electronic shift from a basic molecule adsorbed to the sulfur complex on the other.« less

337 citations

Journal ArticleDOI
TL;DR: Niobium oxides, when small amounts are added to known catalysts, markedly enhance catalytic activity and selectivity and prolong catalyst life for various reactions as discussed by the authors, and they exhibit a pronounced effect as supports of metal or metal oxide catalysts.
Abstract: Salient examples of catalytic application of niobium compounds and materials are demonstrated. Niobium oxides, when small amounts are added to known catalysts, markedly enhance catalytic activity and selectivity and prolong catalyst life for various reactions. Moreover, niobium oxides exhibit a pronounced effect as supports of metal or metal oxide catalysts. Hydrated niobium pentoxide (niobic acid, Nb2O5·nH2O) and niobium phosphate which are unusual solid acids show high catalytic activity, selectivity, and stability for acid-catalyzed reactions. Layer compounds containing niobium combined with metal show peculiar photocatalytic activity. These characteristic features of niobium compounds as catalysts and catalyst components are discussed, their potential significance being emphasized.

336 citations


Cited by
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Journal ArticleDOI
TL;DR: Dehydroisomerization of Limonene and Terpenes To Produce Cymene 2481 4.2.1.
Abstract: 3.2.3. Hydroformylation 2467 3.2.4. Dimerization 2468 3.2.5. Oxidative Cleavage and Ozonolysis 2469 3.2.6. Metathesis 2470 4. Terpenes 2472 4.1. Pinene 2472 4.1.1. Isomerization: R-Pinene 2472 4.1.2. Epoxidation of R-Pinene 2475 4.1.3. Isomerization of R-Pinene Oxide 2477 4.1.4. Hydration of R-Pinene: R-Terpineol 2478 4.1.5. Dehydroisomerization 2479 4.2. Limonene 2480 4.2.1. Isomerization 2480 4.2.2. Epoxidation: Limonene Oxide 2480 4.2.3. Isomerization of Limonene Oxide 2481 4.2.4. Dehydroisomerization of Limonene and Terpenes To Produce Cymene 2481

5,127 citations

Journal ArticleDOI
TL;DR: A survey of the use of cerium oxide and CeO2-containing materials as oxidation and reduction catalysts is presented in this paper, with a special focus on catalytic interaction with small molecules such as hydrogen, carbon monoxide, oxygen, and nitric oxide.
Abstract: Over the past several years, cerium oxide and CeO2-containing materials have come under intense scrutiny as catalysts and as structural and electronic promoters of heterogeneous catalytic reactions. Recent developments regarding the characterization of ceria and CeO2-containing catalysts are critically reviewed with a special focus towards catalyst interaction with small molecules such as hydrogen, carbon monoxide, oxygen, and nitric oxide. Relevant catalytic and technological applications such as the use of ceria in automotive exhaust emission control and in the formulation of SO x reduction catalysts is described. A survey of the use of CeO2-containing materials as oxidation and reduction catalysts is also presented.

3,077 citations

Journal ArticleDOI
TL;DR: In this paper, the open literature concerning chemical and mechanistic aspects of the selective catalytic reduction of NO by ammonia (SCR process) on metal oxide catalysts is reviewed, and the results of spectroscopic studies of the adsorbed surface species, adsorption-desorption measurements, flow reactor and kinetic experiments are analyzed.
Abstract: The open literature concerning chemical and mechanistic aspects of the selective catalytic reduction of NO by ammonia (SCR process) on metal oxide catalysts is reviewed. Catalytic systems based on supported V2O5 (including the industrial TiO2-supported V2O5–WO3 and/or V2O5–MoO3 catalysts) and catalysts containing Fe2O3, CuO, MnOx and CrOx are considered. The results of spectroscopic studies of the adsorbed surface species, adsorption–desorption measurements, flow reactor and kinetic experiments are analyzed. The proposed reaction mechanisms are described and critically discussed. Points of convergence and of disagreement are underlined.

1,946 citations

Journal ArticleDOI
TL;DR: In this article, the infrared spectral performance of N x O y species observed on oxide surfaces [N2O, NO−, NO, (NO)2, N2O3, NO+, NO2 − (different nitro and nitrito anions), NO2, n2O4, N 2O5, NO2 and NO3 − (bridged, bidentate, and monodentate nitrates)] is considered.
Abstract: The infrared spectral performance of the N x O y species observed on oxide surfaces [N2O, NO−, NO, (NO)2, N2O3, NO+, NO2 − (different nitro and nitrito anions), NO2, N2O4, N2O5, NO2, and NO3 − (bridged, bidentate, and monodentate nitrates)] is considered. The spectra of related compounds (N2, H-, and C-containing nitrogen oxo species, C─N species, NH x species) are also briefly discussed. Some guidelines for spectral identification of N x O y adspecies are proposed and the transformation of the nitrogen oxo species on catalyst surfaces are regarded.

1,367 citations