The present invention relates to a Cu-based catalyst, a preparation process thereof and its use as the dehydrogenation catalyst in producing a hydroxyketone compound such as acetoin. Said Cu-based catalyst contains copper, at least one auxiliary metal selected from metal of Group IIA, non-noble metal of Group VIII, metal of Group VIB, metal of Group VIIB, metal of Group IIB and lanthanide metal of periodic table of elements, and an alkali metal, and further contains at least one ketone additive selected from a ketone represented by formula (II) and a ketone represented by formula (II′). Said Cu-based catalyst shows a high the acetoin selectivity as the dehydrogenation catalyst for producing acetoin.
R1-C(═O)—CH(OH)—R2  (II)
R1-C(═O)—CH(═O)—R2  (II′) In formulae (II) and (II′), each group is defined as in the description.

A noble metal-free lanthanum transition metal perovskite catalyst material. The noble metal-free lanthanum transition metal perovskite catalyst material may include a two phase mixture of a lanthanum transition metal perovskite with an alkali or alkaline earth metal carbonate, a lanthanum transition metal perovskite doped with an alkali or alkaline earth metal, or a combination thereof. The lanthanum transition metal perovskite catalyst material provides direct decomposition of NOx into N.sub.2 and O.sub.2 without the presence of a noble metal and in the presence of excess O.sub.2.

A noble metal-free lanthanum transition metal perovskite catalyst material. The noble metal-free lanthanum transition metal perovskite catalyst material may include a two phase mixture of a lanthanum transition metal perovskite with an alkali or alkaline earth metal carbonate, a lanthanum transition metal perovskite doped with an alkali or alkaline earth metal, or a combination thereof. The lanthanum transition metal perovskite catalyst material provides direct decomposition of NOx into N.sub.2 and O.sub.2 without the presence of a noble metal and in the presence of excess O.sub.2.

The present invention relates to: a catalyst for glycerin dehydration; a preparation method therefor; and an acrolein preparation method using the catalyst. According to one embodiment of the present invention, the catalyst is used in glycerin dehydration so as to exhibit high catalytic activity, a high yield and high acrolein selectivity, and has a characteristic in which carbon is not readily deposited, thereby having a long lifetime compared with that of a conventional catalyst.

The present invention relates to: a catalyst for glycerin dehydration; a preparation method therefor; and an acrolein preparation method using the catalyst. According to one embodiment of the present invention, the catalyst is used in glycerin dehydration so as to exhibit high catalytic activity, a high yield and high acrolein selectivity, and has a characteristic in which carbon is not readily deposited, thereby having a long lifetime compared with that of a conventional catalyst.

Provided is a method for producing at least one of an unsaturated aldehyde and an unsaturated carboxylic acid from an alkene by an oxidation reaction, in which a n-layered catalyst layer (n≥2) is provided in a gas flow direction in a reaction tube, two or more kinds of catalysts having different activities are used; and the catalysts are packed in such a manner that dT≤20° C. is satisfied, when a difference between a temperature PT.sub.n of an exothermic peak in a n-th layer as counted from a gas inlet and a minimum value mT.sub.n−1 of a temperature of a catalyst layer which appears between an exothermic peak in a (n-1)th layer and an exothermic peak in a n-th layer from the gas inlet is represented as dT (=PT.sub.n−mT.sub.n−1), and the change rate of dT is 2.5 or less at a reaction bath temperature within a range of ±6° C. of a reaction bath temperature at which the highest yield is obtained.

Provided is a method for producing at least one of an unsaturated aldehyde and an unsaturated carboxylic acid from an alkene by an oxidation reaction, in which a n-layered catalyst layer (n≥2) is provided in a gas flow direction in a reaction tube, two or more kinds of catalysts having different activities are used; and the catalysts are packed in such a manner that dT≤20° C. is satisfied, when a difference between a temperature PT.sub.n of an exothermic peak in a n-th layer as counted from a gas inlet and a minimum value mT.sub.n−1 of a temperature of a catalyst layer which appears between an exothermic peak in a (n-1)th layer and an exothermic peak in a n-th layer from the gas inlet is represented as dT (=PT.sub.n−mT.sub.n−1), and the change rate of dT is 2.5 or less at a reaction bath temperature within a range of ±6° C. of a reaction bath temperature at which the highest yield is obtained.

Disclosed are a mesoporous composite oxide catalyst, a method for preparing the same and a method for synthesizing 1,3-butadidne using the same. The surface area is increased by introducing certain porous silica into preparation of a catalyst for synthesizing 1,3-butadiene, thereby improving a conversion ratio of normal-butene, and selectivity and yield of 1,3-butadiene, and providing economic efficiency from the viewpoint of decreasing an amount of used metal and reducing catalyst production cost.

Disclosed are a mesoporous composite oxide catalyst, a method for preparing the same and a method for synthesizing 1,3-butadidne using the same. The surface area is increased by introducing certain porous silica into preparation of a catalyst for synthesizing 1,3-butadiene, thereby improving a conversion ratio of normal-butene, and selectivity and yield of 1,3-butadiene, and providing economic efficiency from the viewpoint of decreasing an amount of used metal and reducing catalyst production cost.

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.