Patent · US Expired

Low-silica faujasite type zeolite and method for producing the same

US5993773A · kind A · utility

15Cited by
15References
9Claims
0Family size

Assignee

Inventors

Key dates

Filing dateNov 24, 1998
Grant dateNov 30, 1999
Priority date
Expiry dateNov 24, 2018

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S423/21
  • WIPO fieldMaterials, metallurgy
  • WIPO sectorChemistry

Abstract

Disclosed are high purity low-silica faujasite type zeolite showing a faujasite single phase on X-ray diffraction, having a SiO.sub.2 /Al.sub.2 O.sub.3 molar ratio of 1.9 to 2.1 and a water adsorption of 35.0% by weight or more when converted to the Na type, and comprising particles having smaller primary particle size and particles having larger primary particle size, wherein the primary particle size of the smaller particles is from 1 .mu.m to 8 .mu.m, the primary particle size of the larger particles is from 5 .mu.m to 15 .mu.m, and the particles having smaller primary particle size accounts for 90% or more of the total particle number; and a method for producing low-silica faujasite type zeolite having a SiO.sub.2 /Al.sub.2 O.sub.3 molar ratio of 1.9 to 2.1 by mixing an aluminate-containing solution with a silicate-containing solution to allow the resulting solution to gel, followed by aging and crystallization, wherein besides zeolite formed, "zeolite" is added before the termination of the aging, thereby producing the low-silica faujasite type zeolite in high purity on a large scale for a short period of time.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.