Patent · US Expired

Oxidation process

US5254796A · kind A · utility

1Cited by
1References
20Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 17, 1992
Grant dateOct 19, 1993
Priority date
Expiry dateJun 17, 2012

Classification

  • Technology area (CPC A)Human Necessities
  • CPC primaryA62D2101/22
  • WIPO fieldMachine tools
  • WIPO sectorMechanical engineering

Abstract

The invention relates to an ecologically favorable process for the hydrolytic decomposition of halogen-containing compounds of the formula CX.sub.4 or CHX.sub.3 or mixtures of these compounds, in which X as halogen is chlorine or bromine or a combination thereof, in an aqueous-alkaline medium, which comprises first keeping the aqueous-alkaline reaction mixture comprising the abovementioned halogen-containing compounds at a temperature of between 0.degree. and 1000.degree. C. under the autogenous pressure which is formed in a closed reaction vessel for a period of up to 10 hours and then subjecting the mixture to a heat treatment at a temperature of between 70.degree. and 150.degree. C. under the autogenous pressure which is formed therein, in the presence of sulfite. The process according to the invention is particularly suitable for hydrolytic decomposition of halogen-containing reaction products from aqueous-alkaline hypohalite oxidations. The preparation of naphthalene-1,4,5,8-tetracarboxylic acid and its tetraalkali metal salts can be carried out in an ecologically particularly favorable manner by the process according to the invention.

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