A catalyst for performing carbon dioxide reforming of methane to produce syngas, that includes cobalt, nickel and magnesium oxides disposed a support.

The present invention relates to a method for producing a carbon nanotube aggregate whose bulk density is easily controllable. Therefore, the present invention provides a carbon nanotube aggregate suitable for use in various fields.

The invention relates to a catalyst for preparation of butadiene by oxydehydrogenation of butene in a fluidized bed reactor, a method of preparing the same, and use of the same, wherein a method according to an embodiment of the invention comprises: reacting a metal precursor with an alkaline substance to obtain a slurry containing insoluble compound, followed by filtering and washing the slurry; adding a binder and deionized water, followed by agitation to regulate the solid content of the slurry to 10-50%; subjecting the slurry to spray drying granulation, wherein the temperature at the feed port is controlled between 200-400° C., and the temperature at the discharge port is controlled between 100-160° C., to obtain catalyst microspheres; and drying the catalyst microspheres at 80-200° C. for 1-24 h, and then calcining the catalyst microspheres at 500-900° C. for 4-24 h to obtain a catalyst having a general formula of FeXaYbZcOd, comprising Fe, Mg, Zn, Bi, Mo, Mn, Ni, Co, Ba, Ca, and other metals. The catalyst microspheres prepared according to the exemplary method exhibit high mobility, desirable particle size distribution, extremely high mechanical strength and catalytic activity, and are applicable to industrial production of butadiene by oxydehydrogenation of butene in a fluidized bed. When this catalyst is used to prepare butadiene by oxydehydrogenation of butene, the yield of butadiene is 76-86%, and the selectivity to butadiene is 94-97%.

This exhaust gas purifying catalyst is provided with a substrate and a catalyst layer formed on a surface of the substrate. The catalyst layer contains zeolite particles that support a metal, and a rare earth element-containing compound that contains a rare earth element. The rare earth element-containing compound is added in such an amount that the molar ratio of the rare earth element relative to Si contained in the zeolite is 0.001 to 0.014 in terms of oxides.

Disclosed are catalysts, methods, and systems for the bi-reforming of hydrocarbons. The method includes contacting a catalyst material with a reactant feed that includes hydrogen (H.sub.2), carbon monoxide (CO), carbon dioxide (CO.sub.2), methane (CH.sub.4), and water (H.sub.2O) to produce a product stream that has a H.sub.2/CO molar ratio of 1.4:1 to 2:1. The catalyst can have a metal oxide core, a redox metal oxide layer deposited on a surface of the metal oxide core, and a catalytically active metal deposited on the surface of the redox metal oxide layer. A dopant can be included in the redox metal oxide layer. The catalyst can have a corm-shell type structure.

This exhaust gas purifying catalyst is provided with a substrate 10 and a catalyst layer 20 formed on a surface of the substrate 10. The catalyst layer 20 contains zeolite particles 22 that support a metal, and a rare earth element-containing compound 24 that contains a rare earth element. The rare earth element-containing compound 24 is added in such an amount that the molar ratio of the rare earth element relative to Si contained in the zeolite 22 is 0.001 to 0.014 in terms of oxides.

Provided is a nitrogen oxide (NO.sub.X) reduction catalyst including an active site including at least one of a metal vanadate expressed by [Chemical Formula 1] and a metal vanadate expressed by [Chemical Formula 2], and a support for loading the active site thereon.
(M.sub.1).sub.XV.sub.2O.sub.X+5  [Chemical Formula 1] (where M.sub.1 denotes one selected from among manganese (Mn), cobalt (Co), and nickel (Ni), and X denotes a real number having a value between 1 and 3.)
(M.sub.2).sub.YVO.sub.4  [Chemical Formula 2] (where M.sub.2 denotes one selected from among lanthanum (La), cerium (Ce), praseodymium (Pr), neodymium (Nd), promethium (Pm), samarium (Sm), europium (Eu), gadolinium (Gd), terbium (Tb), dysprosium (Dy), holmium (Ho), erbium (Er), thulium (Tm), ytterbium (Yb), and lutetium (Lu), and Y denotes a real number having a value between 0.5 and 1.5).

Provided are a Nb-doped nickel oxide-zirconia composite catalyst, and a method for preparing the same. An excellent methane modification reaction is performed by doping a nickel oxide site with niobium, so that alcohol may be prepared at low costs.

The present invention relates to a bundle-type carbon nanotube which has a bulk density of 25 to 45 kg/m.sup.3, a ratio of the bulk density to a production yield of 1 to 3, and a ratio of a tap density to the bulk density of 1.3 to 2.0, and a method for preparing the same.

A propane gas-utilizing system includes a housing having propane gas and a propane leakage prevention material having a catalyst, scavenger, and/or oxidizer of the propane gas arranged in the housing and including at least one of (a) an oxide material having at least one composition of formula (I): Ru.sub.1-xM.sub.xO.sub.2 (I), where 0<x≤0.1 and M is Ag, K, Pt, Rh, or Ir, or (b) an oxide material having at least one composition of formula (II): Co.sub.3-xM.sub.xO.sub.4 (II), where 0<x≤0.3, and M is Pd, Cu, or Sr, or (c) an oxide material having at least one composition of formula (III): MM′.sub.xO.sub.y (III), where x is a stoichiometric ratio of M′ to M, 0≤x≤1.5, y is a stoichiometric ratio of O to M, 1≤y≤3, M is an alkali metal, and M′ (if x>0) is Y, Ce, Nb, Ta, La, Nd, Mn, Ag, Au, or Cr.