This document relates to oxidative dehydrogenation catalyst materials that include molybdenum, vanadium, oxygen, and iron; oxidative dehydrogenation catalyst materials that include molybdenum, vanadium, oxygen, and aluminum; and oxidative dehydrogenation catalyst materials that include molybdenum, vanadium, oxygen, iron, and aluminum.

Multi-metallic bulk catalysts and methods for synthesizing the same are provided. The multi-metallic bulk catalysts contain nickel, molybdenum tungsten, copper, and optionally, titanium and/or niobium. The catalysts are useful for hydroprocessing, particularly hydrodesulfurization and hydrodenitrogenation, of hydrocarbon feedstocks.

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.

A catalyst composition comprises an acrolein-oxidizing catalyst comprising a mixed metal oxide catalyst of general formula (1):

MoV.sub.aA.sup.1.sub.bA.sup.2.sub.cA.sup.3.sub.dO.sub.m  (I)

in which A.sup.1 comprises at least one element selected from the group consisting of W and Cu; A.sup.2 comprises at least one element selected from the group consisting of Sb, Fe, and Nb; A.sup.3 comprises at least one element selected from the group consisting of Y, Ti, Zr, Hf, Ta, Cr, Mn, Re, Ru, Co, Rh, Ir, Ni, Pd, Pt, Ag, Au, Zn, B, Al, Ga, In, Ge, Sn, Si, Te, Pb, P, As, Bi, Se, rare earth elements, alkaline elements, and alkaline earth elements; a ranges from 0.01 to 1.0; b ranges from 0.01 to 1.5; c ranges from 0 to 1.5; d ranges from 0 to 1.0; and m is dependent on the oxidation state of the other elements. The catalyst composition further comprises a finishing catalyst comprising a mixed metal oxide catalyst of general formula (II):

MoV.sub.wNb.sub.xX.sup.1.sub.yX.sup.2.sub.zO.sub.n  (II)

in which X.sup.1 comprises at least one element selected from the group consisting of Te and Sb; X.sup.2 comprises at least one an element selected from the group consisting of Y, Ti, Zr, Hf, Nb, Ta, Cr, Mn, Re, Fe, Ru, Co, Rh, Ir, Ni, Pd, Pt, Ag, Au, Zn, B, Al, Ga, In, Ge, Sn, Pb, P, As, Bi, Se, rare earth elements and alkaline earth elements; w ranges from 0.01 to 1.0; x ranges from 0.01 to 1.0; y ranges from 0.01 to 1.0; z ranges from 0 to 1.0; and n is depended on the oxidation state of the other elements. The finishing catalyst does not contain W or Cu, and has an X-ray diffraction pattern showing an orthorhombic phase as the major crystal phase with main peaks with 2θ at 6.7°, 7.8°, 22.1°, and 27.2°. The acrolein-oxidizing catalyst has a different chemical composition than the finishing catalyst. A process for producing acrylic acid is also disclosed.

The present invention pertains to a catalyst for use in the selective catalytic reduction (SCR) of nitrogen oxides cornprising: —a ceramic candle filter substrate and—a coating which comprises an oxidic metal carrier comprising an oxide of titanium and a catalytic metal oxide which comprises an oxide of vanadium wherein the mass ratio vanadium/titanium is 0.03 to 0.27, —wherein the mass ratio is calculated based on the mass of vanadium metal and titanium metal, and—wherein the catalyst comprises from about 1 to about 10% by weight of the catalytically active material, and—wherein the catalytic metal oxide is adsorbed onto the surface of the oxidic metal carrier.

A method for producing a catalyst for unsaturated carboxylic acid synthesis is proposed. The method includes: obtaining a dried product by drying and heat-treating a starting material mixed liquid in which supply source compounds of respective catalyst component elements are integrated; and forming a catalyst precursor by supporting powder to be supported on a carrier in the form of a particle aggregate. The powder to be supported is either the dried product or obtained from the dried product. The method further includes calcining the catalyst precursor to form the catalyst. The mass loss rate of the powder to be supported at 300° C. is less than 5 percent by mass, and the difference between the mass loss rate of the powder at 370° C. and the mass loss rate of the powder at 300° C. is not less than 1 percent by mass and not more than 6 percent by mass.

A method for preparing an active catalyst for high-efficiency denitration is disclosed. The method includes: a catalyst raw material is charged into a denitration reactor, NH.sub.3 and an inert gas are introduced and then heating is performed, and the temperature is held and then natural cooling is performed, thereby obtaining the catalyst. The active catalyst can greatly improve the denitration activity in low temperature range, and can not only improve the denitration efficiency under the condition without SO.sub.2 and H.sub.2O, but also can improve the denitration efficiency under the condition with both SO.sub.2 and H.sub.2O. The service life of the catalyst is prolonged under the premise of not changing the existing catalyst preparation process, and the economic benefit is significant. The denitration efficiency of a powder catalyst can be increased by 25%, and the denitration efficiency of a honeycombed catalyst or a corrugated catalyst can be increased by 20%.

An iron-free supported catalyst for the selective conversion of hydrocarbons to carbon nanotubes may include cobalt and vanadium as active catalytic metals in any oxidation state on a catalyst support comprising aluminum oxide hydroxide. The mass ratio of cobalt to vanadium is between 2 and 15; the mass ratio of cobalt to aluminum is between 5.8 10.sup.−2 and 5.8 10.sup.−1; and the mass ratio vanadium to aluminum is between 5.8 10.sup.−3 and 8.7 10.sup.−2. The present disclosure is further related to a method for the production of this iron-free supported catalyst and to a method for the production of carbon nanotubes using the iron-free supported catalyst.

The present invention relates to an impregnated supported catalyst, a carbon nanotube aggregate, and a method for producing the carbon nanotube aggregate. The carbon nanotube aggregate includes a four-component catalyst in which catalytic components and active components are supported on a granular support, and bundle type carbon nanotubes grown on the catalyst. The carbon nanotube aggregate has an average particle diameter of 100 to 800 μm, a bulk density of 80 to 250 kg/m.sup.3, and a spherical or potato-like shape.

Processes and associated reaction systems for the oxidative dehydrogenation of an alkane containing 2 to 6 carbon atoms, preferably ethane or propane, more preferably ethane, are provided. In particular, a process is provided that comprises supplying a feed gas comprising the alkane and oxygen to a reactor vessel that comprises an upstream and downstream catalyst bed; contacting the feed gas with an oxidative dehydrogenation catalyst in the upstream catalyst bed, followed by contact with an oxidative dehydrogenation/oxygen removal catalyst in the downstream catalyst bed, to yield a reactor effluent comprising the alkene; and supplying an upstream coolant to an upstream shell space of the reactor vessel from an upstream coolant circuit and a downstream coolant to a downstream shell space of the reactor vessel from a downstream coolant circuit.