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Naotsugu Itoh

Bio: Naotsugu Itoh is an academic researcher from Utsunomiya University. The author has contributed to research in topics: Membrane reactor & Hydrogen. The author has an hindex of 34, co-authored 126 publications receiving 3610 citations. Previous affiliations of Naotsugu Itoh include National Institute of Advanced Industrial Science and Technology & National Chemical Laboratory.


Papers
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Journal ArticleDOI
04 Jan 2002-Science
TL;DR: An efficient process using a shell-and-tube reactor, in which a gaseous mixture of benzene and oxygen is fed into a porous alumina tube coated with a palladium thin layer, attained phenol formation selectivities of 80 to 97% at benzene conversions of 2 to 16% below 250°C.
Abstract: Existing phenol production processes tend to be energy-consuming and produce unwanted by-products. We report an efficient process using a shell-and-tube reactor, in which a gaseous mixture of benzene and oxygen is fed into a porous alumina tube coated with a palladium thin layer and hydrogen is fed into the shell. Hydrogen dissociated on the palladium layer surface permeates onto the back and reacts with oxygen to give active oxygen species, which attack benzene to produce phenol. This one-step process attained phenol formation selectivities of 80 to 97% at benzene conversions of 2 to 16% below 250°C (phenol yield: 1.5 kilograms per kilogram of catalyst per hour at 150°C).

478 citations

Journal ArticleDOI
TL;DR: In this paper, the cyclohexane deshydrogenation in benzene and hydrogene is reversible, and a membrane de palladium is used to separer l'hydrogene au fur and a mesure de sa formation.
Abstract: La deshydrogenation du cyclohexane en benzene et hydrogene est une reaction reversible; pour obtenir une reaction complete, on utilise une membrane de palladium pour separer l'hydrogene au fur et a mesure de sa formation

290 citations

Journal ArticleDOI
TL;DR: In this article, a tubular alpha alumina substrate with 0.7μm pore size and 40% porosity was used as the membrane substrate and an intermediate alpha alumina layer was formed by dip-coating over the substrate.

152 citations

Journal ArticleDOI
TL;DR: In this paper, the results of characterization for reduced Ni/MgO catalysts showed that Ni metal and NiO-mgO phase are formed after the reduction of calcined catalyst by H2 and Ni metal surface area decreased with increase in calcination temperatures.

147 citations

Journal ArticleDOI
TL;DR: In this article, the authors show that all electron scalar relativistic (AER) calculations are essential to obtain the correct site-preference, atop followed by bridge and then hollow (fcc and hcp).

105 citations


Cited by
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Journal ArticleDOI
TL;DR: Biomass is an important feedstock for the renewable production of fuels, chemicals, and energy, and it recently surpassed hydroelectric energy as the largest domestic source of renewable energy.
Abstract: Biomass is an important feedstock for the renewable production of fuels, chemicals, and energy. As of 2005, over 3% of the total energy consumption in the United States was supplied by biomass, and it recently surpassed hydroelectric energy as the largest domestic source of renewable energy. Similarly, the European Union received 66.1% of its renewable energy from biomass, which thus surpassed the total combined contribution from hydropower, wind power, geothermal energy, and solar power. In addition to energy, the production of chemicals from biomass is also essential; indeed, the only renewable source of liquid transportation fuels is currently obtained from biomass.

3,644 citations

Journal ArticleDOI
TL;DR: Hydrogenation of Alkenes and Arenes by Nanoparticles 2624 3.1.2.
Abstract: 2.5. Stabilization of IL Emulsions by Nanoparticles 2623 3. Hydrogenations in ILs 2623 3.1. Hydrogenation on IL-Stabilized Nanoparticles 2623 3.1.1. Hydrogenation of 1,3-Butadiene 2623 3.1.2. Hydrogenation of Alkenes and Arenes 2624 3.1.3. Hydrogenation of Ketones 2624 3.2. Homogeneous Catalytic Hydrogenation in ILs 2624 3.3. Hydrogenation of Functionalized ILs 2625 3.3.1. Selective Hydrogenation of Polymers 2625 3.4. Asymmetric Hydrogenations 2626 3.4.1. Enantioselective Hydrogenation 2626 3.5. Role of the ILs Purity in Hydrogenation Reactions 2628

1,996 citations

Journal ArticleDOI
TL;DR: Several biomass hydrothermal conversion processes are in development or demonstration as mentioned in this paper, which are generally lower temperature (200-400 °C) reactions which produce liquid products, often called bio-oil or bio-crude.
Abstract: Hydrothermal technologies are broadly defined as chemical and physical transformations in high-temperature (200–600 °C), high-pressure (5–40 MPa) liquid or supercritical water. This thermochemical means of reforming biomass may have energetic advantages, since, when water is heated at high pressures a phase change to steam is avoided which avoids large enthalpic energy penalties. Biological chemicals undergo a range of reactions, including dehydration and decarboxylation reactions, which are influenced by the temperature, pressure, concentration, and presence of homogeneous or heterogeneous catalysts. Several biomass hydrothermal conversion processes are in development or demonstration. Liquefaction processes are generally lower temperature (200–400 °C) reactions which produce liquid products, often called “bio-oil” or “bio-crude”. Gasification processes generally take place at higher temperatures (400–700 °C) and can produce methane or hydrogen gases in high yields.

1,822 citations

Journal ArticleDOI
TL;DR: The direct synthesis of H 2O2 from O2 and H2 using a variety of catalysts, and the factors influencing the formation and decomposition of H2O2 are examined in detail in this Review.
Abstract: Hydrogen peroxide (H2O2) is widely used in almost all industrial areas, particularly in the chemical industry and environmental protection. The only degradation product of its use is water, and thus it has played a large role in environmentally friendly methods in the chemical industry. Hydrogen peroxide is produced on an industrial scale by the anthraquinone oxidation (AO) process. However, this process can hardly be considered a green method. It involves the sequential hydrogenation and oxidation of an alkylanthraquinone precursor dissolved in a mixture of organic solvents followed by liquid–liquid extraction to recover H2O2. The AO process is a multistep method that requires significant energy input and generates waste, which has a negative effect on its sustainability and production costs. The transport, storage, and handling of bulk H2O2 involve hazards and escalating expenses. Thus, novel, cleaner methods for the production of H2O2 are being explored. The direct synthesis of H2O2 from O2 and H2 using a variety of catalysts, and the factors influencing the formation and decomposition of H2O2 are examined in detail in this Review.

1,773 citations