Nippon Kayaku Kabushiki Kaisha

Tatsuhiko Kurakami

Atsushi Sudo

Toshitake Kojima

Kazuo Shiraishi

Shigeo Hayashimoto

Tomoaki Kobayashi

Yuuta Nakazawa

Tomoyuki Kawamura

Yasushi Kobayashi

Susumu Matsumoto

Hideki Sugi

Yoshimasa Seo

Hiroyoshi Nowatari

Ryota Hiraoka

Fumio Sakai

Masashi Hashiba

Motohiko Sugiyama

Hideo Yoshida

Yoshiko Shoya

Toru Kawaguchi

Hideomi Sakai

Masaki Nakahara

Eiji Nishimura

Kouichi Tamura

Toru Toki

Yuta Nakazawa

Shigeo Nippon Kayaku Kabushiki Kaisha Hayashimoto

The present invention clarifies the characteristic of the hygroscopicity of the catalyst for producing acrylic acid and finds out a relationship between the water amount of the catalyst and the catalytic performance as the catalyst for producing acrylic acid, and provides an excellent catalyst. Provided is a catalyst for producing acrylic acid, which contains molybdenum and vanadium as essential active components, in which the amount of water contained in the catalyst is 0.01 mass % or more and 0.53 mass % or less.

Catalyst for producing acrylic acid and method for producing acrylic acid

A method for producing at least one oxidation product selected from the group consisting of acrolein and acrylic acid is provided. This method can alleviate concerns about deterioration of a gas-phase oxidation catalyst and reaction runaway in a restart period after a shutdown, and can allow the reaction to proceed in a stable state. Using a fixed-bed reactor filled with a gas-phase oxidation catalyst, at least one source gas selected from the group consisting of propylene and acrolein is subjected to a gas-phase contact oxidation reaction while a heating medium is caused to contact with or circulate through the fixed-bed reactor and thereby to heat the fixed-bed reactor. The temperature of the heating medium when the load is maximum in the restart period after the shutdown is controlled to be lower than the temperature of the heating medium when the load is maximum in an initial start-up period.

Restarting method

The present invention relates to a method for producing an unsaturated carboxylic acid using a catalyst having both a high catalytic performance and a high mechanical strength, and in the method, a supported catalyst obtained by feeding a liquid binder component and a catalytic active component containing molybdenum and vanadium and/or a precursor thereof into a rolling granulator and conducting granulation at a relative centrifugal acceleration of 0.5 G or more and 30 G or less is used.

Method for producing unsaturated carboxylic acid and supported catalyst

Provided is a catalyst having high activity and yield of a target product for producing an unsaturated aldehyde and/or an unsaturated carboxylic acid and further having high mechanical strength. The catalyst is a catalyst prepared by a method in which a catalyst formulation satisfies specified atomic ratios; and in the preparation thereof, a molybdenum component raw material is an ammonium molybdate, a solvent for dissolving the ammonium molybdate is water, a bismuth component raw material is bismuth nitrate, and a solvent for dissolving bismuth nitrate is a nitric acid aqueous solution, and the weight of water for dissolving the ammonium molybdate, the weight of the nitric acid aqueous solution for dissolving the bismuth nitrate, and the acid concentration of the nitric acid aqueous solution are satisfied with specified ranges, respectively.

Catalyst for producing unsaturated aldehyde and/or unsaturated carboxylic acid, method for producing same, and method for producing unsaturated aldehyde and/or unsaturated carboxylic acid

Provided is a method of subjecting an alkene to partial oxidation by using a fixed bed multitubular reactor, thereby producing an unsaturated aldehyde and/or an unsaturated carboxylic acid each corresponding to the alkene, wherein a plurality of catalyst layers formed by N division (N is N&#x2267;2) with respect to a gas flow direction of a reaction tube are provided, and when a change (&#xb0; C.) of hot spot temperature per 1&#xb0; C. change of reaction bath temperature in the catalyst layer is designated as Sn, at least one of the plurality of catalyst layers is regulated to Sn&#x2266;6.

Method for producing unsaturated aldehyde and/or unsaturated carboxylic acid

Provided is a method capable of producing acrolein and/or acrylic acid, or methacrolein and/or methacrylic acid, stably in a high yield over a long period of time advantageously even in a high-load reaction, and the method is a method in which when preparing two or more kinds of catalysts having different formulations and stacking two or more layers in the axial direction of the tube, the catalysts are filled in such a manner that not only the component amount of bismuth relative to molybdenum decreases from the gas inlet side toward the gas outlet side, but also the component amount of iron relative to molybdenum increases from the gas inlet side toward the gas outlet side.

A catalyst and a catalyst packing schedule are designed so that a relation between the raw material conversion rate at which the yield of the objective product becomes maximum and the raw material conversion rate at which a high and low correlation between maximum temperature of the catalyst layer present closest to a reaction gas inlet side Zin and maximum temperature of the catalyst layer present closest to a reaction gas outlet side Zout is reversed satisfies a specific condition of 0.5&#x2266;Cmax&#x2212;Ccrs&#x2266;5, in which Cmax: a raw material conversion rate at which yield of the objective products becomes maximum; and Ccrs: a raw material conversion rate at which, when maximum temperature of the catalyst layer Zin is regarded as Tin, maximum temperature of the catalyst layer Zout is regarded as Tout, and the raw material conversion rate is changed, a high and low correlation between Tin and Tout is reversed.

Process for producing unsaturated aldehyde and/or unsaturated carboxylic acid

The present invention relates to a method for producing acrylic acid through vapor-phase contact oxidation of acrolein, wherein a reactor tube is divided into at least two catalyst layers, and catalysts having a higher activity are charged in the reactor tube sequentially toward an outlet port side from a material source gas inlet port side for a reaction therein to give acrylic acid, and wherein a catalyst activity-controlling method is a method comprising: a step of mixing a molybdenum-containing compound, a vanadium-containing compound, a copper-containing compound and an antimony-containing compound with water, then drying and calcining a resulting mixture, in which a catalytically-active element composition is kept constant but material source compounds are made to vary in type to give composite metal oxides having a different activity.

Catalyst and method for producing acrylic acid

A method for manufacturing a catalyst of which active components are partly neutralized salt of heteropoly acid comprising molybdenum, phosphorus, vanadium, cesium, antimony, and ammonia as essential components, wherein the method is characterized in mixing an antimony compound with a complex oxide of the essential active components in the catalyst containing active components other than antimony, wherein the antimony compound may be added during slurry preparation.

Catalyst for use in production of methacrylic acid and method for manufacturing the same

An object of the present invention is to provide a process for stably producing a catalyst for methacrylic acid production exhibiting high activity and high performance. The process for producing a catalyst for methacrylic acid production of the invention is characterized in that the water content of the catalyst ingredient powder for use in molding, temperature and humidity of a molding step, humidity and temperature of a baking step are individually controlled in the case where molding is performed by a coating method using an Mo&#x2014;V&#x2014;P&#x2014;Cu-based hetero polyacid as an active ingredient and water or an alcohol and/or an aqueous solution of an alcohol as a binder.

Process for producing catalyst for methacrylic acid production and process for producing methacrylic acid

It is an object of the present invention to provide a catalyst having excellent performance and high mechanical strength for use in the production of methacrylic acid. A method for manufacturing a catalyst comprising essential active components of molybdenum, phosphorus, vanadium, cesium, ammonia, copper, and antimony for use in the production of methacrylic acid, comprising drying a slurry prepared by mixing a compound(s) containing the essential active components with water and then calcining the resulting dry powder and molding the calcined powder.

Method for manufacturing catalyst for use in production of methacrylic acid

The present invention relates to a method for producing methacrolein and/or methacrylic acid characterized in that the catalyst filling length of a dehydration catalyst layer is 3 to 20% of the catalyst filling length of an oxidation catalyst layer in a method where raw material gas containing gaseous t-butanol is supplied to a fixed-bed multitubular reactor having a dehydration catalyst layer and an oxidation catalyst layer in this order, from the entrance for raw material gas toward the exit, to produce methacrolein and/or methacrylic acid by dehydration reaction and catalytic gas phase oxidation reaction, and the present invention can increase the conventional yield of approximately 80% to 81 to 82% even when a reaction bath temperature is relatively low (approximately 355&#xb0; C.).

Growing community of inventors

Yamaguchi, Japan

Tatsuhiko Kurakami