Adsorbents composed of inorganic oxides modified with organic dyes

US5766312A · kind A · utility

Assignee

• Engelhard Process Chemicals GmbH · DE

Inventors

• Kirsten Furhmann · Hannover, DE
• Alf-Eric Wischnat · Lehrte, DE
• Thomas Schulz · Bad Pyrmont, DE
• Michael Hoffmeister · Laatzen, DE

Key dates

• Filing date: Mar 18, 1997
• Grant date: Jun 16, 1998
• Expiry date: Mar 18, 2017

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10T428/2993
• WIPO field: Chemical engineering
• WIPO sector: Chemistry

Abstract

Particulate adsorbents composed of inorganic oxides impregnated with an indicator dye selected from the group consisting of phenolphthalein, cresol red and thymol blue; a method for the production thereof, and a method for adsorptive drying of neutral gases using the aforementioned particulate adsorbents, whereby the degree of water absorption by the adsorbent particles is indicated by a reversible color change.