Silicate-bound zeolite granulates, process for their production and use

US4714690A · kind A · utility

Assignee

• Degussa AG · DE

Inventors

• Hans Strack · Alzenau, DE
• Peter Kleinschmit · Hanau, DE

Key dates

• Filing date: Oct 24, 1985
• Grant date: Dec 22, 1987
• Expiry date: Oct 24, 2005

Classification

• Technology area (CPC B): Performing Operations; Transporting
• CPC primary: B01J20/183
• WIPO field: Chemical engineering
• WIPO sector: Chemistry

Abstract

Silicate-bound zeolite granulates are disclosed wherein the zeolite contains a cation which is not present in the binder, and where the zeolite can also contain the binder cation. The granulates are produced by placing powdered zeolite in a mixer, adding sodium silicate solution, mixing until zeolite granulates with a grain size of at least 0.1 mm are obtained, optionally after-rolling the zeolite granulates. The moist zeolite granulates can be initially dried at temperatures of 20 degrees to 39 degrees C., where the carbon dioxide content of the drying air is adjusted to less than 200 ppm. Thereafter, a second drying step can be carried out at temperatures of 40 degrees to 120 degrees C. as well as a third drying stage at 121 degrees to 200 degrees C. under otherwise identical conditions. The products may be activated at temperatures of 600 degrees C. maximum. The zeolite granulates thus obtained are then treated with a first aqueous metal salt solution, washed and then optionally treated with a second aqueous metal salt solution, washed and dried again at 40 degrees to 200 degrees C., preferably 100 degrees to 120 degrees C., and then optionally calcined to 300 degrees to 650 deg…