Sumitomo Chemical Company, Limited

Nippon Shokubai Kagaku Kogyo Co., Ltd.

Tadashi Abe

Yasuhiko Mori

Michio Kato

Masami Ayano

Masanori Moriwaki

Yukio Aoki

Tetsuya Suzuta

Hiroyuki Uhara

Tetsuya Ohrui

Masao Sada

Takaaki Tanaka

Mitsuyoshi Manabe

Koji Deguchi

Tsunejiro Kawaguchi

Michio Katoh

A start-up method of a process for producing chlorine from hydrogen chloride has a mixed gas producing step of producing a mixed gas containing chlorine from hydrogen chloride, a compressed mixed gas producing step of introducing the mixed gas into an inlet of a compressor and compressing the mixed gas in compressor, a purifying step of introducing the compressed mixed gas into a purifying column and separating the compressed mixed gas into purified chlorine and impurities by distillation, and a recompressing step of introducing the purified chlorine into an inlet of the compressor and compressing the mixed gas and the purified chlorine.

Start-up method for producing chlorine

The present invention relates to a multitubular catalytic gas-phase reaction apparatus, comprising a plurality of reaction tubes arranged in parallel, a baffle capable of changing the direction of movement of a heat medium introduced into a reactor shell to a direction perpendicular to the longitudinal direction of the reaction tubes, a space that is disposed in a region including a part of a section where the heat medium flows in the direction of the face of the baffle and does not have the reaction tubes arranged therein, and flow-adjusting rods, disposed in between the space and the reaction tubes, having the same longitudinal direction as that of the reaction tubes.

Multitubular reaction apparatus for contact gas-phase reaction

This invention relates to a improved method for the production of methacrylic acid by the steps of subjecting isobutylene and/or tertiory hutanol to catalytic vapor-phase oxidation with molecular oxygen in a first reactor, then supplying the resultant gax mixture to a second reactor, a rodlike or plate like insert set being placed in the empty space of gas inlet part of the tube of said second reactor.

Method for production of methacrylic acid

A process for separation of methacrylic acid from a methacrylic acid-containing, gaseous reaction mixture obtained by subjecting methacrolein or a compound which can afford methacrolein under reaction conditions and molecular oxygen to gas phase reaction in the presence of a catalyst for oxidation under the coexistence of an inert gas for dilution which comprises (a) cooling the gaseous reaction mixture from a reactor wherein the gas phase reaction has been effected to separate into condensable components including methacrylic acid, acetic acid and water vapor as a condensed liquor and non-condensable components including methacrolein as a non-condensed gaseous mixture, (b) eliminating contaminating methacrolein from the condensed liquor and (c) contacting the resulting condensed liquor with an organic solvent to extract methacrylic acid, followed by separation into an organic solvent solution including methacrylic acid and an aqueous solution as waste water, characterized in that (1) the inert gas for dilution is a non-condensable gas or its mixture with water vapor and (2) the aqueous solution ultimately separated is evaporated and the evolved vapor is subjected to catalytic combustion with molecular oxygen, whereby the amount of waste water to be discharged is much suppressed.

Waste water treatment in the production of methacrylic acid

A process for preparing an acrylic or methacrylic acid ester comprising esterifying the acrylic or methacrylic acid with an alcohol in a water-insoluble and non-reactive organic solvent in the presence of an acid catalyst, the volume ratio of the organic solvent phase to an aqueous solution phase of the acid catalyst being as small as 0.1 to 1.0, whereby a reactor is allowed to be small-sized and a conversion of the esterification is kept high. The acrylic or methacrylic acid ester is useful as a starting material of an acrylic resin or acrylic resin coating, an adhesive or the like.

Process for preparing an acrylic or methacrylic acid ester

A process for purifying crude acrylic acid characterized in that high-purity purified acrylic acid containing little or no low boiling aldehydes is obtained by rectifying a crude acrylic acid consisting essentially of acrylic acid and containing low boiling substances such as acetaldehyde, acrolein, water and acetic acid and/or high boiling substances such as maleic acid, phenol, benzaldehyde and acrylic acid dimer, thereby removing said low boiling substances and then high boiling ones, and then stripping trace amounts of remaining low boiling aldehydes with an inert gas such as nitrogen or air at a liquid to gas molar ratio of 2 to 20.

Growing community of inventors

Ehime, Japan

Tadashi Abe