Nippon Kayaku Kabushiki Kaisha

Yuuta Nakazawa

Tatsuhiko Kurakami

Kazuo Shiraishi

Ryota Hiraoka

Tomoyuki Kawamura

Motohiko Sugiyama

Toru Kawaguchi

Yoshiko Shoya

Masaki Nakahara

Eiji Nishimura

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.

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Yamaguchi, Japan

Yuuta Nakazawa