Production of synthetic zeolite of faujasite structure

US4007253A · kind A · utility

Assignee

• BAYER HEALTHCARE LLC · DE

Inventors

• Lothar Puppe · Burscheid, DE
• Gunter Ulisch
• Friedrich Schwochow · Leverkusen, DE

Key dates

• Filing date: Jul 25, 1975
• Grant date: Feb 8, 1977
• Expiry date: Jul 25, 1995

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10S423/21
• WIPO field: Materials, metallurgy
• WIPO sector: Chemistry

Abstract

A process for the production of synthetic zeolite with the crystal structure of faujasite and with a composition corresponding to the formula: EQU Na.sub.2 O . Al.sub.2 O.sub.3 . (2.5 .+-. 0.5) SiO.sub.2 . n H.sub.2 O (n = 0 to 8) comprising forming a reaction mixture containing Na.sub.2 O, Al.sub.2 O.sub.3, SiO.sub.2 and H.sub.2 O at a temperature of about 60.degree. to 105.degree. C in the presence of about 1 to 20% of finely divided zeolite A based on the weight of Na.sub.2 O + Al.sub.2 O.sub.3 + SiO.sub.2, thereby to form a precipitate which crystallizes to form a synthetic zeolite of faujasite structure. Advantageously the molar ratios of the oxides in the reaction mixture, exclusive of the added zeolite A, are approximately: EQU SiO.sub.2 /Al.sub.2 O.sub.3 = 3 to 5 EQU Na.sub.2 O/SiO.sub.2 = 1.2 to 1.5 EQU H.sub.2 O/Na.sub.2 O = 35 to 45. Even if the mass is stirred during crystallization, little or no phillipsite is produced.