Process for producing (meth)acrylic acid

A process for producing (meth)acrylic acid comprising the step of repeating a crystallization operation "n" times to produce purified (meth)acrylic acid from crude (meth)acrylic acid, wherein: the each crystallization operation comprises a crystallizing step and a melting step; a polymeriz...

Ausführliche Beschreibung

Gespeichert in:
Bibliographische Detailangaben
Hauptverfasser: ISHII, YOSHITAKE, SAKAI, TOYOFUMI, MIYAMOTO, TAKASHI
Format: Patent
Sprache:eng ; fre ; ger
Schlagworte:
Online-Zugang:Volltext bestellen
Tags: Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
Beschreibung
Zusammenfassung:A process for producing (meth)acrylic acid comprising the step of repeating a crystallization operation "n" times to produce purified (meth)acrylic acid from crude (meth)acrylic acid, wherein: the each crystallization operation comprises a crystallizing step and a melting step; a polymerization inhibitor is not added to a (meth)acrylic acid melt obtained in the melting step of the first to n-1 th crystallization operation(s) and a (meth)acrylic acid solution subjected to the crystallizing step of the second to n th crystallization operation(s); and a concentration of a polymerization inhibitor in a (meth)acrylic acid solution subjected to the crystallizing step of the first crystallization operation is adjusted so that a concentration of the polymerization inhibitor in a (meth)acrylic acid solution subjected to the crystallizing step of the n th crystallization operation is 2 ppm by mass or higher.