Process for preparing zeolite powder of type A (IV)

US4551322A · kind A · utility

Assignees

• Degussa AG · DE
• Henkel Kommanditgesellschaft auf Aktien · DE

Inventors

• Hans Strack · Alzenau, DE
• Wolfgang Roebke
• Dieter Kneitel · Rodenbach, DE
• Ehrfried Parr · Rodenbach, DE

Key dates

• Filing date: Mar 14, 1983
• Grant date: Nov 5, 1985
• Expiry date: Mar 14, 2003

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10S423/24
• WIPO field: Basic materials chemistry
• WIPO sector: Chemistry

Abstract

There are produced crystalline zeolite powders of Type A with the composition EQU 1.0.+-.0.2 M.sub.2/n O:Al.sub.2 O.sub.3 :1.85.+-.0.5 SiO.sub.2.y H.sub.2 O where M is a metal cation, n is its valence and y has a value up to 6 with 50 weight % of the particles not over 4.9.mu. and with a particle spectrum ______________________________________ Fraction (.mu.) Portion (weight %) ______________________________________ <3 10 to 60 <5 55 to 95 <10 93 to 99 <15 96 to 100 ______________________________________ by hydrothermally crystallizing a SiO.sub.2, Al.sub.2 O.sub.3, Na.sub.2 O and water containing alkali aluminate, water, silicate synthesis mixture with an optional tempering step wherein in a given case during the crystallization or tempering step instead of stirring shearing forces are employed. The process comprises mixing with stirring (1) an aqueous alkali silicate solution and (2) an aqueous sodium hydroxide with a NaOH content of 0.1 to 500 grams/l and/or (3) aqueous sodium aluminate liquor which contains 0.1 to 100 grams/l of Al.sub.2 O.sub.3 and 1 to 200 grams/l of Na.sub.2 O, one of components (1) and (2) or (3) being present in a container and the other being added theret…