Process for the purification of aqueous peroxygen solutions, solutions obtainable thereby and their use

US7473412B2 · kind B2 · utility

Assignee

• SOLVAY (Société Anonyme) · BE

Inventors

• Robert Owen · Mühlacker, DE
• Juergen Bosse · Wunstorf, DE
• Michael Sell · Peine, DE

Key dates

• Filing date: Oct 1, 2004
• Grant date: Jan 6, 2009
• Expiry date: Oct 1, 2024

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C11D3/3947
• WIPO field: Chemical engineering
• WIPO sector: Chemistry

Abstract

Process for the purification of aqueous peroxygen solutions comprising the treatment of an aqueous peroxygen solution with (a) at least one membrane purification step, (b) optionally at least one ion exchange purification step, (c) optionally at least one dilution step, and (d) at least one other purification step, all of which can be conducted in any sequence. Aqueous peroxygen solutions having a TOC level of less than 1 mg/kg can be obtained by this process. They can be used in the manufacture of semiconductors.