The invention relates to a method for producing butadiene from n-butenes having the steps: A) providing an n-butene-comprising feed gas stream a; B) feeding the n-butene-comprising feed gas stream a and an oxygen-comprising gas into at least one oxidative dehydrogenation zone and oxidatively dehydrogenating n-butenes to butadiene, wherein a product gas stream b comprising butadiene, unreacted n-butenes, steam, oxygen, low-boiling hydrocarbons, high-boiling minor components, optionally carbon oxides and optionally inert gases is obtained; Ca) cooling the product gas stream b by contacting it with a refrigerant and condensing at least a part of the high-boiling minor components; Cb) compressing the remaining product gas stream b in at least one compression step, wherein at least one aqueous condensate stream c1 and a gas stream c2 comprising butadiene, n-butenes, steam, oxygen, low-boiling hydrocarbons, optionally carbon oxides and optionally inert gases is obtained; Da) separating off non-condensable and low-boiling gas components comprising oxygen, low-boiling hydrocarbons, optionally carbon oxides and optionally inert gases as gas stream d2 from the gas stream c2 by absorbing the C.sub.4 hydrocarbons comprising butadiene and n-butenes in an absorption medium, wherein an absorption medium stream loaded with C.sub.4 hydrocarbons and the gas stream d2 are obtained, and Db) subsequently desorbing the C.sub.4 hydrocarbons from the loaded absorption medium stream in a desorption column, wherein a C.sub.4 product gas stream d1 is obtained, Dc) separating off the steam condensate from the absorption medium in a phase separator and vaporizing it in a steam generator and providing it again as stripping gas in the desorption column,
wherein, the steam condensate before the vaporization in a steam generator, is subjected to a pretreatment in a further method step.

The invention relates to a method for producing butadiene from n-butenes having the steps: A) providing a feed gas stream a comprising n-butenes; B) feeding the feed gas stream a comprising the n-butenes and an oxygen-comprising gas into at least one oxidative dehydrogenation zone and oxidatively dehydrogenating n-butenes to butadiene, wherein a product gas stream b comprising butadiene, unreacted n-butenes, steam, oxygen, low-boiling hydrocarbons, high-boiling minor components, possibly carbon oxides and possibly inert gases is obtained; Ca) cooling the product gas stream b by contacting it with a refrigerant and condensing at least a part of the high-boiling minor components; Cb) compressing the remaining product gas stream b in at least one compression stage, wherein at least one aqueous condensate stream c1 and a gas stream c2 comprising butadiene, n-butenes, steam, oxygen, low-boiling hydrocarbons, possibly carbon oxides and possibly inert gases are obtained; Da) separating off non-condensable and low-boiling gas components comprising oxygen, low-boiling hydrocarbons, possibly carbon oxides and possibly inert gases as gas stream d2 from the gas stream c2 by absorbing the C.sub.4 hydrocarbon-comprising butadiene and n-butenes in an absorbent, wherein an absorbent stream loaded with C.sub.4 hydrocarbons and the gas stream d2 are obtained, and Db) subsequent desorption of the C.sub.4 hydrocarbons from the loaded absorbent stream in a desorption column, wherein a C.sub.4 product gas stream d1 is obtained,
wherein a polymerization inhibitor is added in step Db) at the column head of the desorption column.

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 %.

A method for converting alkanes to olefins includes contacting a feed stream comprising alkanes with an oxidative dehydrogenation that does not comprise tellurium catalyst in a reaction zone and dehydrogenating the alkanes without a co-feed of oxygen to yield a product stream having olefins. The oxidative dehydrogenation catalyst has the formula: Mo.sub.vV.sub.wNb.sub.yA.sub.zO.sub.x, where v is 1.0, w is from 0.1 to 0.5, y is from 0.001 to 0.3, A is Bi, Sb, Pr, or mixtures thereof, z is from 0.01 to 0.3, and x charge-balances the structure. The oxidative dehydrogenation catalyst has a crystallographic structure with Pba2-32 space group, characterized by reflections determined with Cu-K.sub. X-ray diffraction (XRD) as follows.

An oxidative dehydrogenation catalyst having: a structure having a formula Mo.sub.vV.sub.wNb.sub.yBi.sub.zO.sub.x, where v is 1, w is from 0.1 to 0.5, y is from 0.001 to 0.3, z is from 0.01 to 0.3, and x is the oxygen content required to charge-balance the structure. The oxidative dehydrogenation catalyst has a Pba2-32 space group, characterized by reflections determined with CuK.sub. X-ray diffraction (XRD) as follows.

The present invention relates to a bismuth molybdate-based composite oxide catalyst having a microporous zeolite coating layer on the surface thereof and thus having high selectivity for 1,3-butadiene, a method of preparing the same, and a method of preparing 1,3-butadiene using the same. The catalyst has a microporous zeolite coating layer, and thus enables only gaseous products (light) to selectively pass through the zeolite coating layer, improving selectivity for 1,3-butadiene.

A method for producing diene comprises a step 1 of obtaining a straight chain internal olefin by removing a branched olefin from a raw material including at least the branched olefin and a straight chain olefin; and a step 2 of producing diene from the internal olefin by oxidative dehydrogenation using a first catalyst and a second catalyst, and the first catalyst has a complex oxide including bismuth, molybdenum and oxygen, and the second catalyst includes at least one selected from the group consisting of silica and alumina.

Disclosed are a composite oxide catalyst for preparing butadiene and a method of preparing the same. More particularly, a composite oxide catalyst, for preparing butadiene, including a metal composite oxide and AlPO.sub.4, and a method of preparing the same are disclosed. According to the present disclosure, a composite oxide catalyst for preparing butadiene, which includes a specific binder material, prevents generation of ingredients with a high boiling point, has superior catalyst strength, catalytic activity and butadiene yield, and a method of preparing the same are provided.

Disclosed are a catalyst composition for oxidative dehydrogenation and a method of preparing the same. More particularly, disclosed is a catalyst composition comprising a multi-ingredient-based metal oxide catalyst and a mixed metal hydroxide. The catalyst composition and the method of preparing the same according to the present disclosure may prevent loss occurring in a filling process due to superior mechanical durability and wear according to long-term use, may inhibit polymer formation and carbon deposition during reaction, and may provide a superior conversion rate and superior selectivity.

The invention provides non-naturally occurring microbial organisms having a butadiene pathway. The invention additionally provides methods of using such organisms to produce butadiene.