Crystalline zeolite powder of type A (VI)

US4303627A · kind A · utility

Assignee

• Degussa & Henkel Kommanditgesellschaft Auf Aktien · DE

Inventors

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

Key dates

• Filing date: Oct 27, 1977
• Grant date: Dec 1, 1981
• Expiry date: Oct 27, 1997

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 1.0.+-.0.2 M.sub.2/n O:Al.sub.2 O.sub.3 :1.85.+-.0.5 SiO.sub.2 .multidot.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 5.9.mu. and with a particle spectrum ______________________________________ Fraction (.mu.) Portion (weight %) ______________________________________ <3 15 to 25 <5 35 to 55 <10 80 to 94 <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 providing water in a container, simultaneously feeding into the water at a temperature of 30.degree. to 100.degree. C. an aqueous sodium aluminate liquor containing 100 to 200 grams/l of Na.sub.2 O and 50 to 150 grams/l of Al.sub.2 O.sub.3 and alkali silicate solution, diluting with water to obtain a gel containing synthesis premixture having the composition SiO…