A method for preparing a mixed-metal oxide catalyst comprising molybdenum, vanadium, at least one of niobium or tantalum, and at least one of tellurium or antimony and useful for the oxidative dehydrogenation of ethane to ethylene, the method comprising preparing a catalyst precursor, pressing the precursor into a dense pellet using a pressure of greater than about 5,000 psi, and annealing the pellet to form the mixed-metal oxide catalyst.

A process for oxidative dehydrogenation of a hydrocarbon to produce an olefin and water may include contacting, in a fluidized bed, the hydrocarbon with a particulate material, which may include at least one oxygen transfer agent (OTA) and at least one fluidization enhancing additive. During at least a portion of contacting the hydrocarbon with the particulate material, the fluidized bed may be at a temperature at or above a melting point of one or more materials of the oxygen transfer agent. Further, during at least a portion of contacting the hydrocarbon with the particulate material, a surface of at least a portion of the OTA may comprise a molten layer. The fluidization enhancing additive may not undergo reduction in the fluidized bed during contacting the hydrocarbon with the particulate material and may be present in an amount that maintains sufficient fluidization of the particulate material.

The present invention provides a method for producing 1,3-butadiene that is capable of suppressing generation of reaction by-products. The method includes: a step (A) of to obtain a produced gas containing 1,3-butadiene; a step (B) of cooling the produced gas; and a step (C) of separating the produced gas cooled in the step (B) into molecular oxygen and inert gases, and other gases containing 1,3-butadiene, by selective absorption into an absorption solvent. In the method, in the step (A), the raw material gas and a molecular oxygen-containing gas are supplied to a fixed-bed reactor with a composite oxide catalyst containing molybdenum and bismuth; the molar ratio of molecular oxygen to n-butene in the gases is 1.0 to 2.0; and the molar ratio of water vapor to n-butene in the gases supplied to the fixed-bed reactor is not more than 1.2.

Disclosed are a molybdenum based composite oxide catalyst, its preparation method and use. The catalyst has the following general formula: BiMo.sub.xM.sub.yN.sub.zO.sub.a; wherein M is one of V, Cr, Mn, Fe, Co, Ni and Cu, or a mixture of two or more of V, Cr, Mn, Fe, Co, Ni and Cu in any ratio; N is one of Na, K, Cs, Ca and Ba, or a mixture of two or more of Na, K, Cs, Ca and Ba in any ratio; x=0.5˜20; y=0.05˜20; z=0.01˜5; a is a number satisfying the valance of each atom. The catalyst is prepared by the following method: firstly mixing a certain amount of the lead metal oxides according to the chemical proportion and then grinding the mixture with high-energy ball milling for a period of time to obtain the molybdenum based composite oxide catalyst. The catalyst exhibits excellent performance when using for preparation of butadiene by oxidative dehydrogenation of butene, and the preparation process is simple, controllable, and repeatable. Waste water or waste gas that is difficult to be treated is not produced during preparation.

The present invention relates to a method for producing butadiene through an oxidative dehydrogenation reaction. The production method according to the present invention may easily regulate an input ratio between oxygen and nitrogen that are used as raw material, such that a loss may be minimized of butadiene that is included in a second fraction stream (purge stream) and discharged to outside of the system. Consequently, an economic competitiveness of the process, such as a reduced raw material cost and an improved productivity may be realized.

An object of the present invention is to suppress performance deterioration of a molybdenum composite oxide-based catalyst at the time of performing gas-phase catalytic partial oxidation with molecular oxygen by using a tubular reactor. The present invention relates to a catalytic oxidation method using a tubular reactor in which a Mo compound layer containing a Mo compound and a composite oxide catalyst layer containing a Mo composite oxide catalyst are arranged in this order from a reaction raw material supply port side and under a flow of a mixed gas containing 75 vol % of air and 25 vol % of water vapor at 440° C., a Mo sublimation amount of the Mo compound is larger than a Mo sublimation amount of the Mo composite oxide catalyst under the same conditions.

A method for producing a conjugated diolefin is configured as follows. A monoolefin having four or more carbon atoms is fed from a plurality of monoolefin feed nozzles. In addition, at least 50% or more of a total amount of an oxygen-containing gas is fed from an oxygen-containing gas feed nozzle located at a bottom of a fluidized bed reactor. Furthermore, the plurality of monoolefin feed nozzles at n places located at heights a1, a2, . . . , and an from the oxygen-containing gas feed nozzle, respectively, feed the monoolefin having four or more carbon atoms at ratios of b1, b2, . . . , bn (b1+b2+ . . . +bn=1), respectively. Furthermore, a weighted mean value represented by the following formula is 100 mm or greater:
weighted mean value=a1*b1+a2*b2+ . . . +an*bn.

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%.

A catalyst for preparing light olefin using direct conversion of syngas is a composite catalyst and formed by compounding component I and component II in a mechanical mixing mode. The active ingredient of component I is a metal oxide; and the component II is one or more than one of zeolite of CHA and AEI structures or metal modified CHA and/or AEI zeolite. A weight ratio of the active ingredients in the component I to the component II is 0.1-20. The reaction process has high product yield and selectivity, wherein the sum of the selectivity of the propylene and butylene reaches 40-75%; and the sum of the selectivity of light olefin comprising ethylene, propylene and butylene can reach 50-90%. Meanwhile, the selectivity of a methane side product is less than 15%.

A method for producing 1,3-butadiene, including: (A) performing an oxidative dehydrogenation reaction between oxygen and a raw material gas including n-butene in the presence of a metal oxide catalyst, thereby obtaining a produced gas containing 1,3-butadiene; (B) washing the produced gas obtained in (A); (C) contacting the produced gas washed in (B) with a cooling medium to cool the produced gas; and (D) separating the produced gas cooled in (C) into molecular oxygen and inert gases, and other gases containing 1,3-butadiene, by selective absorption into an absorption solvent. In (B), the washing of the produced gas includes blowing the produced gas onto a liquid surface of a washing liquid so that the produced gas contacts the liquid surface of the washing liquid.