Nippon Shokubai Co., Ltd.

Tetsuya Kajihara

Yasuhiro Shingai

Tokumasa Ishida

Yukihiro Yoneda

Hajime Matsumoto

Tadayoshi Kawashima

Masatoshi Ueoka

Masahiro Uemura

Sei Nakahara

Yoshitake Ishii

Hideaki Nagano

Kei Hamamoto

Fumio Shibusawa

Sumio Nakashima

Fumio Munechika

Kaoru Iwasaki

Souichi Yamada

This invention discloses a method for producing maleic anhydride comprising an azeotropic distillation step to dehydrate a crude maleic acid-containing aqueous solution, which method is characterized by as an azeotropic solvent (1) using an organic solvent exhibiting a maximum dissolving concentration of the organic solvent in water in the range of 0.1-5% by weight at a temperature of 20&#xb0; C. According to this invention, it is made possible to prevent the occurrence of a blocking substance, allow a continuous operation for a long time, and remove by-produced acid components by a process of distillation for azeotropic dehydration.

Method for production of maleic anhydride

The present invention provides a process for producing a (meth)acrylic ester which enables to obtain a (meth)acrylic ester in an excellent reaction yield. The process for producing a (meth)acrylic ester uses an alcohol and an acid as raw materials and an ion-exchange resin as a catalyst, and the process is characterized by comprising a dehydration step and an esterification step, wherein the esterification reaction step follows the dehydration step in which water impregnated in the ion-exchange resin is removed by using as a dehydrating solvent at least one member selected from the group consisting of the alcohol, the acid, and the resulting ester.

Process for producing (meth)acrylic ester

When carrying out a liquid-phase reaction by using a heterogeneous catalyst, the separation of the heterogeneous catalyst and the reaction liquid is carried out certainly and effectively. A reaction method involves carrying out a reaction in liquid phase by using a heterogeneous catalyst particle in a reactor , and comprises the steps of: (a) allowing a reaction liquid supplied into the reactor from such as a supplying inlet to react in the presence of the heterogeneous catalyst particle , and (b) passing the resultant reaction liquid containing the heterogeneous catalyst particle through a line screen having an opening width where the heterogeneous catalyst particle is not allowed to pass substantially, and then extracting the reaction liquid separated from the heterogeneous catalyst particle from the reactor by way of such as an extracting outlet

Reaction method by using heterogeneous catalyst and reaction apparatus therefor

Process for producing hydroxyalkyl (meth)acrylate

The present invention provides: a production process for a hydroxyalkyl(meth)acrylate, which can raise productivity together with avoiding danger of explosion, and further can suppress side-formation of impurities such as a diester or a monoester wherein the impurities have a bad influence on product quality. When the time from the start of adding an alkylene oxide (AO) till the end of supplying the entirety of the AO is defined as T (hour), the amount of more than 50% of the entirety of the AO is supplied before T/2 (hour) has passed since the start of adding the AO. In addition, when the total amount of an AO as supplied and the time from the start of adding the AO till the end of supplying the entirety of the AO are defined as W (mol) and T (hour) respectively, the supply of the AO is started at a supplying speed V0 (mol/hour) that is faster than the average supplying speed V (&equals;W/T) (mol/hour), and thereafter the supplying speed of the AO is decreased at least once, and then the supply of the entirety of the AO is completed for T (hour) from the start of adding the AO.

Production process for hydroxyalkyl (meth)acrylate

In the operation of producing an alkylamino(meth)acrylate by the reaction of transesterification of an alkyl(meth)acrylate with an alkylamino alcohol, the alkyl alcohol by-produced during the transesterification is distilled in the form of an azeotropic mixture with the alkyl(meth)acrylate, the resultant distillate is purified with an ion-exchange resin and handled, on the other hand, the reaction solution is distilled to allow separation of the catalyst wherein is provided a method and apparatus for effecting, in the production of the alkylamino(meth)acrylate, the distillation under such a condition as represses the amount of in crease of the Michael adduct below 2%.

Method for production of alkylamino(Meth)acrylate and apparatus therefor

The present invention provide a production process for a hydroxyalkyl ester which comprises the step of carrying out a reaction between a carboxylic acid and an alkylene oxide in the presence of a catalyst, wherein the production process sufficiently enhances the conversion or selectivity in the reaction. The production process is characterized in that the reaction is carried out in a reaction liquid under conditions where a relationship a<b is kept throughout the reaction wherein &ldquo;a&rdquo; is a molar concentration (mol %) of the carboxylic acid in the reaction liquid and wherein &ldquo;b&rdquo; is a molar concentration (mol %) of the alkylene oxide in the reaction liquid.

Production process for hydroxyalkyl ester

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Himeji, Japan

Tetsuya Kajihara