The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 19, 1993
Filed:
Jun. 17, 1992
Erwin Dietz, Kelkheim, DE;
Siegfried Schiebler, Bad Soden am Taunus, DE;
Hoechst Aktiengesellschaft, Frankfurt, DE;
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.