Method of producing nitro-phenols
AssigneeAktiebolaget Bofors
InventorsErik Bengtsson, Boris Holm
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Abstract
Preparation of nitro compounds of phenols and alkyl substituted derivatives thereof which includes nitrosating phenols or alkyl derivative thereof, oxidizing the nitroso compound, separating off nitrogen oxides, separating nitro compounds from reaction mixture, and subjecting mother liquor and washing liquids to destructive oxidation at elevated temperatures and recycling nitrogen oxides and nitric acid.
Claims22
A method of producing mono-nitro compounds of monohydric phenol and alkyl substituted derivatives of monohydric phenol which comprises nitrosating said phenol or alkyl substituted derivative of phenol in a nitric acid solution through treatment with nitrogen oxides at temperatures of between +10.degree. and -30.degree. C.;
- oxidizing the nitroso compound at a temperature of between 20.degree. and 45.degree. C. after an increase of the temperature of the nitric acid;
- separating off nitrogen oxides during said oxidizing;
- separating the nitro compound from the reaction mixture through cooling and filtering;
- subjecting the mother liquor and washing liquids to destructive oxidation with nitric acid at a temperature exceeding 130.degree. C. and an increased pressure so that the mother liquor and washing liquids after emitting at least nitrogen oxides and carbon dioxide will substantially contain only nitric acid and water;
- and returning the nitric acid and nitrogen oxides from both the oxidation stage and the destruction stage and using them for new nitrosation and destruction, whereby from the reaction system, is formed said nitro compounds and in addition, substantially only water, carbon dioxide and possibly nitrogen will be emitted.
Dependencies are inferred from the claim text.