Process for the production of a superabsorbent polymer

US8063121B2 · kind B2 · utility

Assignee

• Evonik Stockhausen GmbH · US

Inventors

• Daniel Fricker · Rœschwoog, FR
• Herbert Gartner · Baden-Baden, DE
• Marc Hager · Bischwiller, FR
• Jorg Harren · Baesweiler, DE
• Hans-Peter Kohler · Bühlertal, DE
• Harald Plochinger · Bühl, DE

Key dates

• Filing date: Oct 7, 2009
• Grant date: Nov 22, 2011
• Expiry date: Apr 13, 2030

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C08F2/16
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

The present invention relates to a process for the production of a superabsorbent polymer comprising preparing an aqueous mixture of monomers selected to provide after polymerization a superabsorbent polymer; feeding said monomer mixture to a reactor; subjecting the aqueous monomer mixture in the reactor to free-radical polymerization to obtain a superabsorbent polymer gel; removing the superabsorbent polymer gel from the reactor; and drying the superabsorbent polymer gel. Where at least one off-gas stream removed from any stage of the process is subjected to scrubbing with a basic aqueous solution prior to venting to obtain an aqueous scrubber solution that is at least partially recycled to any of the above steps of the process.