Patent · US Expired

Process for the preparation of urea

US6114579A · kind A · utility

9Cited by
6References
13Claims
0Family size

Assignee

Inventor

Key dates

Filing dateAug 29, 1997
Grant dateSep 5, 2000
Priority date
Expiry dateAug 29, 2017

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02P20/582
  • WIPO fieldOrganic fine chemistry
  • WIPO sectorChemistry

Abstract

In the present process for the preparation of urea, an off-gas stream released during the synthesis of melamine in a high-pressure melamine process which consists predominantly of ammonia and carbon dioxide, is introduced into at least one high-pressure section of a urea stripping plant and is used in the synthesis of urea. The off-gas stream can be used directly without any further treatment.

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