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.

A method for producing butadiene comprises a step of obtaining a product gas containing butadiene, by feeding a raw-material gas containing straight-chain butene and an oxygen-containing gas containing molecular oxygen to a reactor and performing oxidative dehydrogenation reaction in the presence of a catalyst, wherein the catalyst comprises a composite oxide containing molybdenum and bismuth, and the concentration of hydrocarbons having 5 or more carbon atoms in the raw-material gas is 0.05 mol % to 7.0 mol %.

Oxidative dehydrogenation is an alternative to the energy extensive steam cracking process presently used for the production of olefins from paraffins, but has not been implemented commercially partially due to the unstable nature of hydrocarbon/oxygen mixtures, and partially due to the cost involved in the construction of new facilities. An oxidative dehydrogenation chemical complex designed to reduce costs by including integration of an oxygen separation module that also addresses safety concerns and reduces emission of greenhouse gases is described.

A catalyst containing molybdenum, bismuth, and iron, in which R1 represented by the following equation (1) is 0.45 or more and 5.00 or less is provided, and use of the catalyst achieves a high yield, in the case of the use in a gas phase oxidation reaction, particularly in the case of the use in producing an unsaturated aldehyde compound or an unsaturated carboxylic acid compound by a partial oxidation reaction,

[00001]$\begin{array}{cc}R1=\left(\mathrm{maximum}\mathrm{value}\mathrm{of}\mathrm{peak}\mathrm{at}886{\mathrm{cm}}^{-1}?5{\mathrm{cm}}^{-1}\right)?\left(\mathrm{maximum}\mathrm{value}\mathrm{of}\mathrm{peak}\mathrm{at}354{\mathrm{cm}}^{-1}?5{\mathrm{cm}}^{-1}\right)\mathrm{as}\mathrm{measured}\mathrm{by}\mathrm{Raman}\mathrm{spectroscopy}.& \left(1\right)\end{array}$

Oxidative dehydrogenation of light paraffins, such as ethane at moderate temperatures (<500 C.) to produce ethylene without the formation of side products such as acetic acid and/or other oxygenated hydrocarbons is achieved using tellurium-free, multimetallic catalysts possessing orthorhombic M1 phase and other crystalline structures that have an important role for obtaining high performance catalysts for the oxidative dehydrogenation of ethane to ethylene. Such catalysts are prepared using thermal and hydrothermal methods.

A supported molded catalyst having increased hardness, the supported molded catalyst being capable of improving the long-term stability of a reaction for producing a conjugated diolefin by catalytic oxidative dehydrogenation from a mixed gas including a monoolefin having 4 or more carbon atoms and molecular oxygen; and a method for producing the catalyst is provided. A molded catalyst for conjugated diolefin production, the molded catalyst being a catalyst for producing a conjugated diolefin by a catalytic oxidative dehydrogenation reaction from a mixed gas including a monoolefin having 4 or more carbon atoms and molecular oxygen, and being produced by molding a composite metal oxide and a glass fiber-like inorganic auxiliary agent.

Disclosed is a catalyst system, and its methods of preparation 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 C3 to C4 aliphatic alcohols that are derivable from biomass, such as, propanols, propanediols, and isobutanol, 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 a C3 aliphatic alcohol 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.

Provided is a method for producing an unsaturated aldehyde and/or an unsaturated carboxylic acid, which enables one to achieve an operation stably over a long period of time while improving an effective yield, even in a high-load reaction, and in the method for producing an unsaturated aldehyde and/or an unsaturated carboxylic acid, multilayer filling of stacking two or more catalyst layers each containing a complex metal oxide catalyst in the axial direction of the tube under specified conditions is performed, and the catalyst layer on the most gas outlet side in the tube axis contains a catalyst containing a compound represented by a specified formulation formula.

Process for producing a multimetal oxide catalyst comprising molybdenum, chromium and at least one further metal by mixing of a pulverulent multimetal oxide comprising molybdenum and at least one further metal but no chromium with pulverulent chromium(III) oxide and thermal treatment of the resulting pulverulent mixture in the presence of oxygen at a temperature in the range from 350 C. to 650 C.

A process for preparing butadiene from n-butenes, comprising the steps of: absorbing C4 hydrocarbons comprising butadiene and n-butenes, obtained from oxidative dehydrogenation of n-butenes, in an aromatic hydrocarbon solvent as an absorbent and removing uncondensable and low-boiling gas constituents comprising oxygen, low-boiling hydrocarbons, any carbon oxides, aromatic hydrocarbon solvent and any inert gases as gas stream d2, giving an absorbent stream laden with C4 hydrocarbons and the gas stream d2, and then desorbing the C4 hydrocarbons from the laden absorbent stream, giving a C4 product gas stream d1; and at least partly recycling the gas stream d2 as cycle gas stream a2 into the oxidative dehydrogenation zone, wherein the content of aromatic hydrocarbon solvent in the cycle gas stream a2 is limited to less than 1% by volume.