Provided is a technique of producing isoprene from 3-methyl-1,3-butanediol or 1,3-butadiene from 1,3-butanediol by using a single catalyst. A catalyst produces a conjugated diene containing zirconium oxide and calcium oxide in order to produce isoprene by removing two water molecules from one 3-methyl-1,3-butanediol molecule or produce 1,3-butadiene by removing two water molecules from one 1,3-butanediol molecule. Furthermore, a method for producing a conjugated diene includes a step of obtaining a fluid containing a conjugated diene that is isoprene or 1,3-butadiene by bringing a fluid containing 3-methyl-1,3-butanediol or a fluid containing 1,3-butanediol into contact with the catalyst for producing a conjugated diene as a single catalyst so as to cause a dehydration reaction to proceed.

Provided is a technique of producing isoprene from 3-methyl-1,3-butanediol or 1,3-butadiene from 1,3-butanediol by using a single catalyst. A catalyst produces a conjugated diene containing zirconium oxide and calcium oxide in order to produce isoprene by removing two water molecules from one 3-methyl-1,3-butanediol molecule or produce 1,3-butadiene by removing two water molecules from one 1,3-butanediol molecule. Furthermore, a method for producing a conjugated diene includes a step of obtaining a fluid containing a conjugated diene that is isoprene or 1,3-butadiene by bringing a fluid containing 3-methyl-1,3-butanediol or a fluid containing 1,3-butanediol into contact with the catalyst for producing a conjugated diene as a single catalyst so as to cause a dehydration reaction to proceed.

A method for preparing a catalyst for a dehydration reaction of 3-hydroxypropionic acid, the catalyst for dehydration reaction of 3-hydroxypropionic acid, and a method for producing acrylic acid using the same.

A catalyst for forming a synthetic gas containing hydrogen and carbon monoxide from a hydrocarbon-based gas, the catalyst containing a complex oxide having a perovskite structure, wherein the complex oxide has a crystal phase containing CaZrO.sub.3 as a primary component and contains Ru and at least one of Ce and Y.

A layered diesel oxidation catalyst for treatment of exhaust gas emissions from a diesel engine comprising: a flow-through monolith substrate having a honeycomb structure and comprising a front zone and a rear zone, wherein the front zone of the substrate comprises a combination of layers, one on top of another and comprising two or more of layers A, B and C; and the rear zone comprises Layer D, wherein: Layer A comprises platinum, palladium, or combinations thereof on a molecular sieve; Layer B comprises 1) platinum, palladium, or combinations thereof on a refractory metal oxide support; and 2) an alkaline earth metal, preferably barium, strontium or combinations thereof; Layer C comprises 1) a platinum group metal, which is platinum or a combination of both platinum and palladium on a refractory metal oxide support; and 2) a promoter metal, which is manganese and/or bismuth; and layer D comprises 1) platinum or a combination of both platinum and palladium on a refractory metal oxide support; and 2) manganese (Mn).

Porous alumina having excellent heat resistance and coking resistance is provided. The porous alumina can include silica and barium oxide added to aluminum oxide, wherein a ratio of SiO2 addition amount to a total mass of aluminum oxide and SiO2 addition amount is defined as SiO2 addition ratio (mass %), a ratio of BaO addition amount to a total mass of aluminum oxide and SiO2 addition amount is defined as BaO addition ratio (mass %), when the SiO2 addition ratio is within a range of 3 mass % or less and the BaO addition ratio is within a range of 14 mass % or less, the silica and the barium oxide are respectively added to the aluminum oxide so that a specific surface area of the porous alumina measured by a measuring method after heat treatment is equal to or larger than a reference specific surface area of reference porous alumina.

Porous alumina having excellent heat resistance and coking resistance is provided. The porous alumina can include silica and barium oxide added to aluminum oxide, wherein a ratio of SiO2 addition amount to a total mass of aluminum oxide and SiO2 addition amount is defined as SiO2 addition ratio (mass %), a ratio of BaO addition amount to a total mass of aluminum oxide and SiO2 addition amount is defined as BaO addition ratio (mass %), when the SiO2 addition ratio is within a range of 3 mass % or less and the BaO addition ratio is within a range of 14 mass % or less, the silica and the barium oxide are respectively added to the aluminum oxide so that a specific surface area of the porous alumina measured by a measuring method after heat treatment is equal to or larger than a reference specific surface area of reference porous alumina.

A particulate filter disclosed herein includes a wall-flow structure substrate 10 and a wash coat layer 20 held inside a partition 16 of the substrate 10. The wash coat layer 20 includes an inlet layer 22 formed to have predetermined length L.sub.A and thickness T.sub.A from near an end thereof on an exhaust gas inflow side X1, and an outlet layer 24 formed to have predetermined length L.sub.B and thickness T.sub.B from near an end thereof on an exhaust gas outflow side X2. The inlet layer 22 and the outlet layer 24 partially overlap each other. In the particulate filter disclosed herein, the inlet layer 22 contains a precious metal catalyst, while the outlet layer 24 contains substantially no precious metal catalyst. The length L.sub.A of the inlet layer is 50% or more and 75% or less of a total length L of the partition 16. Thus, the particulate filter is capable of achieving both PM collection performance and pressure-drop reduction performance at high levels.

A particulate filter disclosed herein includes a wall-flow structure substrate 10 and a wash coat layer 20 held inside a partition 16 of the substrate 10. The wash coat layer 20 includes an inlet layer 22 formed to have predetermined length L.sub.A and thickness T.sub.A from near an end thereof on an exhaust gas inflow side X1, and an outlet layer 24 formed to have predetermined length L.sub.B and thickness T.sub.B from near an end thereof on an exhaust gas outflow side X2. The inlet layer 22 and the outlet layer 24 partially overlap each other. In the particulate filter disclosed herein, the inlet layer 22 contains a precious metal catalyst, while the outlet layer 24 contains substantially no precious metal catalyst. The length L.sub.A of the inlet layer is 50% or more and 75% or less of a total length L of the partition 16. Thus, the particulate filter is capable of achieving both PM collection performance and pressure-drop reduction performance at high levels.

The present invention relates to a dry reforming catalyst in which an active material is impregnated on the surface of a metal oxide support and the active material is surrounded by a surfactant, a method of preparing the same, and a method of producing a synthetic gas using the catalyst. Since the surfactant on the surface of the active material prevents the active material from being sintered and the active material surface from being covered with carbon, the dry reforming catalyst exhibits high activity at high temperature for a long period of time without having to use a precious metal, and thus is useful for the production of a synthetic gas.