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.

Embodiments of methods of synthesizing a metathesis catalyst system, which include impregnating tungsten oxide on silica support in the presence of a precursor to produce a base catalyst; calcining the base catalyst; impregnating a metal oxide co-catalyst comprising a metal oxide onto the surface of the base catalyst to produce a doped catalyst; and calcining the doped catalyst to produce a metathesis catalyst system. Further embodiments of processes for the production of propylene, which include contacting a hydrocarbon feedstock comprising a mixture of 1-butene and 2-butene with embodiments of the metathesis catalyst system to produce, via metathesis conversion, a product stream comprising propylene.

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.

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.

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.

Disclosed are a ferrite catalyst and preparation methods thereof. The catalyst is provided with a formula below, wherein A is Mg atom, Zn atom or a mixture of both atoms at any ratio; D is one or more atoms selected from the group consisting of Ni, Co, W, Mn, Ca, Mo or V atom; Z is a catalyst carrier, which is one or more selected from the group consisting of calcium phosphate, calcium dihydrogen phosphate, aluminum phosphate, aluminum dihydrogen phosphate, ferric phosphate, magnesium phosphate, zinc phosphate, Mg—Al hydrotalcite, calcium carbonate, magnesium carbonate; a=0.01-0.6; b=0-0.30; c is a number balancing each valence; x, y represent the amounts of principal catalyst and carrier Z respectively, wherein the weight ratio y/x=0.5:1-7:1.
x(FeA.sub.aD.sub.bO.sub.c)/yZ

A method for producing a multiphase mixed-oxide catalyst including at least one active phase based on bismuth molybdate and one co-catalyst based on iron molybdate and at least one amongst the two elements cobalt and nickel, includes the following steps:

preparing a mixture of the precursors of said-mixed oxides in a solvent,

making said precursors react through a microwave-assisted hydrothermal reaction, and

isolating the mixed oxides to obtain the catalyst.

A catalyst and a catalytic system prepared in this manner are related to the method as well as the uses of this catalyst and of this catalytic system, in particular in the oxidation of propene into acrolein.

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.

The present disclosure relates to a reactor and a method of operation for an exothermal process being catalyzed by a catalytically active material receiving a reactant gas and providing a product gas, in which said exothermal process has a heat development having a potential for thermally degrading said catalytically active material, and which exothermal process operates at a temperature at which the reactants and at least 80% or all of the products are present as gases, said method comprising the steps of a) directing the reactant gas to a first zone of a material catalytically active in the exothermal process producing an first product gas, and b) directing the first product gas to a second zone of a material catalytically active in the exothermal process producing a product gas, with the option of fully or partially by-passing either said first zone or said second zone, while directing a non-condensing gas stream having a temperature at least 50° C. lower than the product gas to said by-passed zone, wherein the choice of by-passing said zone is made based on the time of operation or a process parameter reflecting the catalytic activity of the zone of catalytically active material which is not by-passed with the associated benefit of reducing the extent of thermal deactivation of the catalytically active material, and thus increasing the overall lifetime of the catalytically active material.

A method is provided comprising exposing a supported heterogeneous metathesis catalyst to an olefin compound for an activation time at an activation temperature; exposing the activated supported heterogeneous metathesis catalyst to a reactant capable of undergoing a metathesis reaction for a reaction time at a reaction temperature to produce metathesis products; and exposing the deactivated supported heterogeneous metathesis catalyst to a regenerating compound for a regeneration time at a regeneration temperature. The activity of the regenerated supported heterogeneous metathesis catalyst may be substantially the same or greater than the activity of the activated supported heterogeneous metathesis catalyst prior to deactivation. The activation temperature may be greater than the reaction temperature. The regenerating compound may be a second olefin compound or an inert gas.