A method comprising treating combustion exhaust gas containing nitrogen oxides in the presence of a denitration catalyst to remove nitrogen oxides from the combustion exhaust gas, wherein the denitration catalyst is composed of a shaped product comprising a catalyst component, the shaped product has micro cracks in a mesh pattern or a bipectinate pattern on the surface of the shaped product, and the micro cracks have a 95% crack width of 100 μm or less and a crack area ratio variation coefficient of 0.7 or less.

Provided is a method for producing an unsaturated aldehyde including subjecting an alkene to partial oxidation using a fixed bed multi-tube reactor to produce the corresponding unsaturated aldehyde, in which n catalyst layers (n is 2 or more) in a gas flow direction in a reaction tube are provided, when a filling length of the catalyst layers from a first catalyst layer to an (n-1)th catalyst layer from a gas inlet side of the reaction tube is L, and a filling length of an nth catalyst layer from the gas inlet side of the reaction tube is Ln, a relationship between L and Ln satisfies the following equation (1):

[00001]$\begin{array}{cc}1<L\text{/}\mathrm{Ln}\le 3,& \left(1\right)\end{array}$ and a composition of a catalytically active component contained in the catalyst layers from the first catalyst layer to the (n-1)th layer from the gas inlet side of the reaction tube is different from a composition of a catalytically active component contained in the nth catalyst layer from the gas inlet side of the reaction tube.

Provided is a method for producing an unsaturated aldehyde including subjecting an alkene to partial oxidation using a fixed bed multi-tube reactor to produce the corresponding unsaturated aldehyde, in which n catalyst layers (n is 2 or more) in a gas flow direction in a reaction tube are provided, when a filling length of the catalyst layers from a first catalyst layer to an (n-1)th catalyst layer from a gas inlet side of the reaction tube is L, and a filling length of an nth catalyst layer from the gas inlet side of the reaction tube is Ln, a relationship between L and Ln satisfies the following equation (1):

[00001]$\begin{array}{cc}1<L\text{/}\mathrm{Ln}\le 3,& \left(1\right)\end{array}$ and a composition of a catalytically active component contained in the catalyst layers from the first catalyst layer to the (n-1)th layer from the gas inlet side of the reaction tube is different from a composition of a catalytically active component contained in the nth catalyst layer from the gas inlet side of the reaction tube.

A catalyst comprising molybdenum, bismuth, iron, and nickel, wherein a proportion of a surface concentration of the nickel to a bulk concentration of the nickel is 0.60 to 1.20.

A catalyst comprising molybdenum, bismuth, iron, and nickel, wherein a proportion of a surface concentration of the nickel to a bulk concentration of the nickel is 0.60 to 1.20.

Mixed metal oxide catalysts having an amorphous content of not less than 40 wt. % are prepared by calcining the catalyst precursor fully or partially enclosed by a porous material having a melting temperature greater than 600° C. in an inert container including heating the catalyst precursor at a rate from 0.5 to 10° C. per minute from room temperature to a temperature from 370° C. to 540° C. under a stream of pre heated gas chosen from steam and inert gas and mixtures thereof at a pressure of greater than or equal to 1 psig having a temperature from 300° C. to 540° C. and holding the catalyst precursor at that temperature for at least 2 hours and cooling the catalyst precursor to room temperature.

Mixed metal oxide catalysts having an amorphous content of not less than 40 wt. % are prepared by calcining the catalyst precursor fully or partially enclosed by a porous material having a melting temperature greater than 600° C. in an inert container including heating the catalyst precursor at a rate from 0.5 to 10° C. per minute from room temperature to a temperature from 370° C. to 540° C. under a stream of pre heated gas chosen from steam and inert gas and mixtures thereof at a pressure of greater than or equal to 1 psig having a temperature from 300° C. to 540° C. and holding the catalyst precursor at that temperature for at least 2 hours and cooling the catalyst precursor to room temperature.

The present invention relates to a catalyst for oxidative dehydrogenation of butene and a method for producing the same. The catalyst for oxidative dehydrogenation of butene has a large amount of Mo—Bi phase acting as a reaction active phase on the surface, and therefore, can exhibit high catalytic activity, high conversion rate and high butadiene selectivity in the oxidative dehydrogenation of butene.

The present invention relates to a catalyst for oxidative dehydrogenation of butene and a method for producing the same. The catalyst for oxidative dehydrogenation of butene has a large amount of Mo—Bi phase acting as a reaction active phase on the surface, and therefore, can exhibit high catalytic activity, high conversion rate and high butadiene selectivity in the oxidative dehydrogenation of butene.

Disclosed is a catalyst system, its methods of preparation and its use for producing, among others, alkenes and/or saturated or unsaturated oxygenates and, which include at least one of an aldehyde and an acid (such as propyl aldehyde, acrolein, acrylic acid, isobutyl aldehyde, methacrolein, methacrylic acid), comprising subjecting the corresponding an alcohol or a diol selected from the group consisting of propanol, propanediol and isobutanol that is derivable from biomass, to a vapor phase process over the catalytic system described herein in the presence of a gas mixture of oxygen, air or nitrogen and/or other suitable diluting gas. In the case where one of 1-propanol, or 1,2-propanediol or 1,3-propanediol or a mixture thereof is subjected to a vapor phase catalytic process over the said catalytic system in the presence of air or oxygen, and a co-fed gas, such as nitrogen or other diluting gas, the product is at least one of propylene, propyl aldehyde, acrolein and acrylic acid. In the case where isobutanol is subjected to such a process, the product is at least one of isobutylene, isobutyl aldehyde, methacrolein and methacrylic acid. The catalyst system comprises a single catalytic zone or multi-catalytic zones, in each of which the composition of the co-feed and other reaction parameter can be independently controlled.