Continuous method for preparation of granulated sodium perborate

US4968500A · kind A · utility

Assignee

• Degussa AG · DE

Inventors

• Birgit Bertsch-Frank · Rheinfelden (Baden), DE
• Klaus Mueller · Hanau, DE
• Thomas Lieser · Hanau, DE

Key dates

• Filing date: May 17, 1989
• Grant date: Nov 6, 1990
• Expiry date: May 17, 2009

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C01B15/126
• WIPO field: Materials, metallurgy
• WIPO sector: Chemistry

Abstract

The spray drying of a solution containing hydrogen peroxide and sodium metaborate to obtain primary particles which are immediately conveyed after leaving the drying zone to a granulating device and are then granulated in the presence of free and/or perborate water of crystallization. The granulated materials are dried, if necessary. The generally amorphous primary particles are converted into granulated materials with at least partially crystalline structure and significantly improved shelf life. The work is performed with advantage in a spray dryer with integrated fluid bed or in a compressing granulating device. The method is suitable for preparing perborate granulated materials with over 10% by wt., especially perborate monohydrate granular materials with 14-16% by wt. active oxygen.