Patent · US Active

Process for preparation of highly pure, non-yellowing methacrylic acid

US9290431B2 · kind B2 · utility

0Cited by

3References

9Claims

0Family size

Assignee

Evonik Röhm GmbH · DE

Inventors

Zhengfeng Zhang · Quzhou, CN
Gerhard Koelbl · Gernsheim, DE
Lorenza Sartorelli · Ober-Ramstadt, DE
Horst Hiltner · Munster, DE
Huisheng Wang · Palo Alto, US
Mirko Michel · Dortmund, DE

Key dates

Filing date	Apr 22, 2013
Grant date	Mar 22, 2016
Priority date	—
Expiry date	Apr 22, 2033

Classification

Technology area (CPC C)Chemistry; Metallurgy
CPC primaryC07C51/48
WIPO fieldOrganic fine chemistry
WIPO sectorChemistry

Abstract

This invention relates to a process of preparing highly pure, non-yellowing (meth)acrylic acid necessary for high-tech applications requiring long-tem color stability in the presence of amines. Process for the preparation of highly pure, non-yellowing (meth)acrylic acid comprising the steps: f) Condensation of a (meth)acrylic acid-containing gas phase obtained via a gas phase oxidation process of a C4-compound to generate an aqueous (meth)acrylic acid solution g) Separation of the (meth)acrylic acid from the aqueous (meth)acrylic acid solution to obtain crude (meth)acrylic acid h) Rectification of the crude (meth)acrylic acid to obtain pure (meth)acrylic acid via a sidestream outlet of the rectification column i) Treatment of the pure (meth)acrylic acid generated in step c) with an ion exchange resin j) Distillation of the (meth)acrylic acid generated in step d).

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.