The present invention relates to carbon nanotubes having a pore volume of 0.94 cm.sup.3/g or more, and being an entangled type, a method of manufacturing the same, and a positive electrode for a primary battery which comprises the same.

The present invention relates to carbon nanotubes having a pore volume of 0.94 cm.sup.3/g or more, and being an entangled type, a method of manufacturing the same, and a positive electrode for a primary battery which comprises the same.

Methods for gas-phase deoxygenation of a bio-oil are provided. In embodiments, such a method comprises exposing a bio-oil vapor comprising hydrocarbon compounds having oxygenated aromatic groups, to hydrogen gas in the presence of catalyst under conditions to induce deoxygenation of the oxygenated aromatic groups to provide a deoxygenated aromatic species, wherein the catalyst is a transition metal-incorporated mesoporous silicate having platinum deposited thereon and the transition metal is selected from Nb, W, Zr, and combinations thereof. The transition metal-incorporated mesoporous silicate catalysts are also provided.

The invention relates to a catalyst composition suitable for the dehydrogenation of paraffins having 2-8 carbon atoms comprising zinc oxide and titanium dioxide, optionally further comprising oxides of cerium (Ce), dysprosium (Dy), erbium (Er), europium (Eu), gadolinium (Gd), lanthanum (La), neodymium (Nd), praseodymium (Pr), samarium (Sm), terbium (Tb), ytterbium (Yb), yttrium (Y), tungsten (W) and Zirconium (Zr) or mixtures thereof, wherein said catalyst composition is substantially free of chromium and platinum. The catalysts possess unique combinations of activity, selectivity, and stability. Methods for preparing improved dehydrogenation catalysts and a process for dehydrogenating paraffins having 2-8 carbon atoms, comprising contacting the mixed metal oxide catalyst with paraffins are also described. The catalyst may also be disposed on a porous support in an attrition-resistant form and used in a fluidized bed reactor.

As a hydrocarbon production system that synthesizes hydrocarbons using water and carbon dioxide as raw materials, a hydrocarbon production system capable of producing hydrocarbons by securing hydrogen and carbon monoxide required for hydrocarbon synthesis is provided. In a hydrocarbon production system that produces hydrocarbons from at least water and carbon dioxide, the hydrocarbon production system includes at least an electrolytic reaction unit, a reverse water-gas shift reaction unit, and a hydrocarbon synthesis reaction unit.

A nitrogen oxide storage material comprising: Mg.sub.1-yAl.sub.2O.sub.4-y, wherein y is a number satisfying 0≤y≤0.2, a noble metal, an oxide of a metal other than the noble metal, and a barium compound, the noble metal, the oxide, and the barium compound being loaded on Mg.sub.1-yAl.sub.2O.sub.4-y. The metal oxide comprises at least one metal oxide selected from zirconium oxide, praseodymium oxide, niobium oxide, and iron oxide.

The present specification discloses a membrane reactor comprising a reaction region; a permeate region; and a composite membrane disposed at a boundary of the reaction region and the permeate region, wherein the reaction region comprises a bed filled with a catalyst for dehydrogenation reaction, wherein the composite membrane comprises a support layer including a metal with a body-centered-cubic (BCC) crystal structure, and a catalyst layer including a palladium (Pd) or a palladium alloy formed onto the support layer, wherein ammonia (NH.sub.3) is supplied to the reaction region, the ammonia is converted into hydrogen (H.sub.2) by the dehydrogenation reaction in the presence of the catalyst for dehydrogenation reaction, and the hydrogen permeates the composite membrane and is emitted from the membrane reactor through the permeate region.

An ammonia synthesis catalyst having high activity is obtained by having a two-dimensional electride compound having a lamellar crystal structure such as Ca.sub.2N support a transition metal. However, since the two-dimensional electride compound is unstable, the stability of the catalyst is low. In addition, in cases where a two-dimensional electride compound is used as a catalyst support, it is difficult to shape the catalyst depending on reactions since the two-dimensional electride compound has poor processability. A composite which includes a transition metal, a support and a metal amide compound, wherein the support is a metal oxide or a carbonaceous support; and the metal amide compound is a metal amide compound represented by general formula (1). M(NH.sub.2).sub.x . . . (1) (In general formula (1), M represents at least one metal atom selected from the group consisting of Li, Na, K, Be, Mg, Ca, Sr, Ba and Eu; and x represents the valence of M.)

A core-shell composite material may include a core consisting of Nb-doped TiO.sub.2 of formula TiNbO.sub.x; and a shell consisting of a homogeneous layer of Pt or Pt alloy of 1 to 50 ML in thickness. The core-shell composite material may in particular find application in fuel cells.

The present specification discloses a membrane reactor comprising a reaction region; a permeate region; and a composite membrane disposed at a boundary of the reaction region and the permeate region, wherein the reaction region comprises a bed filled with a catalyst for dehydrogenation reaction, wherein the composite membrane comprises a support layer including a metal with a body-centered-cubic (BCC) crystal structure, and a catalyst layer including a palladium (Pd) or a palladium alloy formed onto the support layer, wherein ammonia (NH.sub.3) is supplied to the reaction region, the ammonia is converted into hydrogen (H.sub.2) by the dehydrogenation reaction in the presence of the catalyst for dehydrogenation reaction, and the hydrogen permeates the composite membrane and is emitted from the membrane reactor through the permeate region.