Ciba-geigy Ag

Bayer Aktiengesellschaft

Hans Frey

Bernhard Albrecht

Vinzenz Habermacher

Guido Steffan

Horst Behre

Axel Vogel

Wolfgang Schenk

Paul Havalda

Lutz Kienitz

Georg Halfter

A process for producing the magnesium salt of 3-nitro-naphthalene-1,5-disulfonic acid by sulfonating naphthalene, nitrating the sulfonation product, and separating the pure magnesium salt of 3-nitronaphthalene-1,5-disulfonic acid, which process comprises:

Process for producing the magnesium salt of

A process for the reduction of aromatic nitro compounds to amino compounds in the liquid phase using iron as reducing agent, which comprises carrying out the reduction continuously such that the reducing iron, based on the amount of nitro compound present in the reactor, is present in an amount substantially in excess of the stoichiometric amount, and effecting the continuous removal of the reaction products such that the substantial excess of reducing iron is also constantly present in the reactor during the reduction.

Continuous reduction process

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Bettingen, Switzerland

Hans Frey