Patent · US Expired

Removal of nitric acid from nitric acid-sulfuric acid mixtures

US4155989A · kind A · utility

4Cited by
5References
8Claims
0Family size

Assignee

Inventor

Key dates

Filing dateNov 14, 1977
Grant dateMay 22, 1979
Priority date
Expiry dateNov 14, 1997

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC01B17/94
  • WIPO fieldMaterials, metallurgy
  • WIPO sectorChemistry

Abstract

Mixtures of nitric acid and sulfuric acid containing in excess of 70% sulfuric acid are denitrated by the addition of sufficient sulfur dioxide to such mixtures to convert the nitric acid to gaseous nitrogen oxides and vaporizing them from the solution in which they are formed. The process is particularly valuable for the treatment of spent nitration acids.

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