Method for purification of formaldehyde, use thereof and plastics produced therewith

US6229053A · kind A · utility

Assignee

• Ticona LLC · US

Inventors

• Werner Sievers · Frankfurt, DE
• Elke Schweers · Bad Soden, DE
• Christine Meister · Pocking, DE

Key dates

• Filing date: May 25, 2000
• Grant date: May 8, 2001
• Expiry date: May 25, 2020

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07D323/06
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

Abstract A process for purifying formaldehyde in which the formaldehyde is scrubbed with alcohol in an absorption unit and in the course of this reacted virtually completely to form the hemiformal and is simultaneously separated off from gaseous impurities in a first purification step. In a desorption unit, the residual impurities are then converted into a gaseous state and separated off from the liquid hemiformal, whereupon the purified hemiformal is thermally cleaved into alcohol and formaldehyde in a pyrolysis unit. The formaldehyde thus prepared is suitable, for example, for preparing oligomers, polymers, dyestuffs and fertilizers, as well as for the treatment of seeds. Process for purifying formaldehyde, its use and plastics prepared using it