A catalyst composition comprising a mixture of (a) a zeolite compound in an amount of from 10% to 60% by weight, wherein the zeolite compound comprises cations selected from Fe.sup.2+, Fe.sup.3+, Cu.sup.+, Cu.sup.2+ or mixtures thereof, and (b) a ceria/zirconia/alumina composite oxide, wherein the alumina content in said composite oxide is in the range of 20 to 80% by weight, in particular of 40 to 60% by weight,
a catalyst comprising such catalyst composition and its use for exhaust gas after-treatment of diesel and lean burn engines.

A catalyst composition comprising a mixture of (a) a zeolite compound in an amount of from 10% to 60% by weight, wherein the zeolite compound comprises cations selected from Fe.sup.2+, Fe.sup.3+, Cu.sup.+, Cu.sup.2+ or mixtures thereof, and (b) a ceria/zirconia/alumina composite oxide, wherein the alumina content in said composite oxide is in the range of 20 to 80% by weight, in particular of 40 to 60% by weight,
a catalyst comprising such catalyst composition and its use for exhaust gas after-treatment of diesel and lean burn engines.

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.

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.

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 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 is a multi-component bismuth molybdate catalyst for production of butadiene which comprises bismuth, molybdenum and at least one metal having a monovalent, divalent or trivalent cation, and further comprises cesium and potassium and thus has advantages of improving conversion ratio, yield and selectivity of butadiene and of providing stability of process operation.

Disclosed is a multi-component bismuth molybdate catalyst for production of butadiene which comprises bismuth, molybdenum and at least one metal having a monovalent, divalent or trivalent cation, and further comprises cesium and potassium and thus has advantages of improving conversion ratio, yield and selectivity of butadiene and of providing stability of process operation.