Patent · US Expired

Preparation of crystalline 4A zeolites

US5474753A · kind A · utility

1Cited by
14References
23Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 16, 1994
Grant dateDec 12, 1995
Priority date
Expiry dateMay 16, 2014

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S423/24
  • WIPO fieldBasic materials chemistry
  • WIPO sectorChemistry

Abstract

Crystalline 4A zeolites having high calcium ion exchange capacity, well adapted as builder materials for detergent compositions, are prepared by directly admixing an aqueous sodium silicate solution with a first aqueous sodium aluminate solution in a first reaction vessel to form a hydrogel therefrom, and transferring the hydrogel thus formed to a discrete crystallization zone and therein contacting such hydrogel with a crystallization-effecting amount of a second aqueous sodium aluminate solution to convert same into a crystalline 4A zeolite, and, advantageously, filtering, washing and optionally drying such crystalline 4A zeolite.

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