An object of the present invention is to provide a process for producing an oxide catalyst used in a vapor-phase catalytic oxidation or vapor-phase catalytic ammoxidation reaction of propane or isobutene, which enables a catalyst demonstrating favorable yield to be stably produced. According to the present invention, there is provided a process for producing an oxide catalyst used in a vapor-phase catalytic oxidation or vapor-phase catalytic ammoxidation reaction of propane or isobutane, comprising the steps of: (i) preparing a catalyst raw material mixture containing Mo, V and Nb and satisfying the relationships of 0.1≦a≦1 and 0.01≦b≦1 when atomic ratios of V and Nb to one atom of Mo are defined as a and b, respectively; (ii) drying the catalyst raw material mixture; and (iii) calcining a particle, in which a content of the particle having a particle diameter of 25 μm or less is 20% by mass or less and a mean particle diameter is from 35 to 70 μm, in an inert gas atmosphere.

The present invention provides a production method which is capable of stably producing a catalyst that enables a production of methacrylic acid with high selectivity. A method of producing a catalyst used for a production of methacrylic acid includes (i) preparing a slurry A1 containing a heteropolyacid containing at least phosphorus and molybdenum or a salt of the heteropolyacid containing at least phosphorus and molybdenum, (ii) preparing a slurry A2 satisfying the following Formula (I) and Formula (II) using the slurry A1, (iii) mixing the slurry A2 and a raw material liquid B containing a cationic raw material to prepare a slurry C, and (iv) drying the slurry C, α.sub.A2/α.sub.A1≤0.95 (I), 2≤D.sub.A2≤50 (II), wherein, in Formula (I), α.sub.A1 represents a half-value width (μm) of a particle size distribution of the slurry A1, α.sub.A2 represents a half-value width (μm) of a particle size distribution of the slurry A2, and in Formula (II), D.sub.A2 represents a median diameter (μm) of the particle size distribution of the slurry A2.

The present invention provides a production method which is capable of stably producing a catalyst that enables a production of methacrylic acid with high selectivity. A method of producing a catalyst used for a production of methacrylic acid includes (i) preparing a slurry A1 containing a heteropolyacid containing at least phosphorus and molybdenum or a salt of the heteropolyacid containing at least phosphorus and molybdenum, (ii) preparing a slurry A2 satisfying the following Formula (I) and Formula (II) using the slurry A1, (iii) mixing the slurry A2 and a raw material liquid B containing a cationic raw material to prepare a slurry C, and (iv) drying the slurry C, α.sub.A2/α.sub.A1≤0.95 (I), 2≤D.sub.A2≤50 (II), wherein, in Formula (I), α.sub.A1 represents a half-value width (μm) of a particle size distribution of the slurry A1, α.sub.A2 represents a half-value width (μm) of a particle size distribution of the slurry A2, and in Formula (II), D.sub.A2 represents a median diameter (μm) of the particle size distribution of the slurry A2.

Provided are a preparation method for a propylene epoxidation catalyst, and a use thereof. During the preparation, an alkoxide solution of a prepared active component and a silica gel support are mixed, then a rotary evaporation treatment is performed on the mixture to remove a low-carbon alcohol to obtain a catalyst precursor, and then the obtained catalyst precursor is subjected to calcination and silylation treatments to obtain the propylene epoxidation catalyst. The catalyst is prepared in a simple process, can be applied to the chemical process of preparing propylene oxide by propylene epoxidation, has high average selectivity to propylene oxide, and has industrial application prospect.

The present invention relates to a high-performance polyoxometalate catalyst and a method of preparing the same. More particularly, the present invention provides a high-performance polyoxometalate catalyst, the activity and selectivity of which may be improved by controlling the content of vanadium and the like and which has superior reproducibility and may unsaturated carboxylic acid from unsaturated aldehyde in a high yield for a long time, a method of preparing the same, and the like.

The present invention relates to a high-performance polyoxometalate catalyst and a method of preparing the same. More particularly, the present invention provides a high-performance polyoxometalate catalyst, the activity and selectivity of which may be improved by controlling the content of vanadium and the like and which has superior reproducibility and may unsaturated carboxylic acid from unsaturated aldehyde in a high yield for a long time, a method of preparing the same, and the like.

A hydrocracking process for converting a petroleum feed to lower boiling products. The process comprises hydrotreating a petroleum feed in a pre-treating zone in the presence of hydrogen to produce a hydrotreated effluent stream comprising a liquid product. At least a portion of the hydrotreated effluent stream is then passed to an MMS catalyst zone, and then to a hydrocracking zone. In one embodiment, the MMS catalyst zone comprises a self-supported multi-metallic catalyst prepared from a precursor in the oxide or hydroxide form. The percentage work of the hydrotreating in the pre-treating zone is maintained at a level of at least 56%.

A hydrocracking process for converting a petroleum feed to lower boiling products. The process comprises hydrotreating a petroleum feed in a pre-treating zone in the presence of hydrogen to produce a hydrotreated effluent stream comprising a liquid product. At least a portion of the hydrotreated effluent stream is then passed to an MMS catalyst zone, and then to a hydrocracking zone. In one embodiment, the MMS catalyst zone comprises a self-supported multi-metallic catalyst prepared from a precursor in the oxide or hydroxide form. The percentage work of the hydrotreating in the pre-treating zone is maintained at a level of at least 56%.

Provided is a catalyst structure which prevents an increase in pressure loss by a simple construction while the gas flow is efficiently stirred by a structure making contact between adjacent catalyst elements. The catalyst structure is provided with a first flat-plate part and a second flat-plate part which support, on surfaces thereof, a constituent having catalytic activity to an exhaust gas and face each other, and a stirring part which is provided in such a manner as to come into contact first with the first flat-plate part and the second flat-plate part in an extending manner from the first flat-plate part to the second flat-plate part at a prescribed angle with respect to the direction in which the exhaust gas flows.

Provided is a catalyst structure which prevents an increase in pressure loss by a simple construction while the gas flow is efficiently stirred by a structure making contact between adjacent catalyst elements. The catalyst structure is provided with a first flat-plate part and a second flat-plate part which support, on surfaces thereof, a constituent having catalytic activity to an exhaust gas and face each other, and a stirring part which is provided in such a manner as to come into contact first with the first flat-plate part and the second flat-plate part in an extending manner from the first flat-plate part to the second flat-plate part at a prescribed angle with respect to the direction in which the exhaust gas flows.