Method of recovering polyvinyl chloride from solvent-containing waste PVC pastes

US5158984A · kind A · utility

Assignee

• Carl Freudenberg · DE

Inventors

• Jorg Hausdorf · Fürth, DE
• Bardo Anselm · Hemsbach, DE
• Steffen Kosack · Haßloch, DE
• Peter Schafer · Pfungstadt, DE
• Rolf Schneider · Burgstetten, DE
• Stefan Seiderer · Gorxheimertal, DE

Key dates

• Filing date: Mar 30, 1992
• Grant date: Oct 27, 1992
• Expiry date: Mar 30, 2012

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y02W30/62
• WIPO field: Other special machines
• WIPO sector: Mechanical engineering

Abstract

Reuseable polyvinyl chloride is recovered from solvent-loaded waste polyvinyl chloride paste by adding one twentieth of the paste weight of an acyl polyethylene glycol ester, then adding about twice the paste weight of water, while stirring, driving off the solvent by steam distillation, separating the solvent from the resulting two-phase distillate, and filtering off and drying the polyvinyl chloride granules floating in water left behind in the distillation residue.