Patent · US Active

Recovery of nitrating acid mixtures from nitration processes

US7470826B2 · kind B2 · utility

7Cited by

9References

19Claims

0Family size

Assignee

JOSEF MEISSNER GMBH & CO. KG · DE

Inventors

Heinrich Hermann · Cologne, DE
Jürgen Gebauer · Geldern, DE
Peter Konieczny · Teltow, DE
Mirko Händel · Neunkirchen, DE

Key dates

Filing date	Oct 16, 2006
Grant date	Dec 30, 2008
Priority date	—
Expiry date	Oct 16, 2026

Classification

Technology area (CPC C)Chemistry; Metallurgy
CPC primaryC07C201/16
WIPO fieldOrganic fine chemistry
WIPO sectorChemistry

Abstract

The invention relates to a process for removing and recovering nitrating acid mixtures, in particular nitric acid, sulphuric acid and oxides of nitrogen, from the nitrated crude products occurring in the nitration of nitratable aromatic compounds after the nitrating acid has been separated off, by acidic scrubbing by means of a multistage extraction process, the extraction process comprising a cross-current extraction with downstream countercurrent extraction. The process permits essentially complete recovery of the abovementioned acids, including the oxides of nitrogen, in high concentrations, so that they can be recycled to the nitration and no longer pollute the wastewater.

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