High solids content titanium dioxide suspension

US5393510A · kind A · utility

Assignee

• Rheox Inc. · US

Inventors

• Siegfried Blumel · Mettmann, DE
• Achim Hartmann · Pulheim, DE
• Hans Thumm
• Hans-Hermann Luginsland · Leverkusen, DE
• Franz Rosendahl · Leverkusen, DE

Key dates

• Filing date: Jul 12, 1993
• Grant date: Feb 28, 1995
• Expiry date: Jul 12, 2013

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C01P2006/80
• WIPO field: Basic materials chemistry
• WIPO sector: Chemistry

Abstract

A finely divided chloride process titanium dioxide prepared without the use of a dispersing agent. The slurry is dewatered via filtration, and the resulting filter cake is made flowable with an anionic dispersing agent. In order to attain a filter cake with very high solids content, the slurry should contain no, or only very few, multivalent anions. The conditions regarding the content of multivalent anions of the slurry are achieved by selection of suitable dechlorinating agents, especially hydrogen peroxide. The filter cake is thixotropic and is made flowable by the fact that it is put into the "diluted" dispersing agent, especially into a part of the titanium dioxide suspension to which the required quantity of dispersing agent has previously been added. Titanium dioxide suspensions with solids content of approximately 78% are thereby obtained and are of particular use in the paper industry.