VERFAHREN ZUR HERSTELLUNG VON AROMATISCHEN AMINOSULFONSAEUREN

1. A process for the preparation of an aromatic aminosulfonic acid of the formula I see diagramm : EP0146889,P6,F3 where the individual radicals R**1 can be identical or different, at least one radical R**1 is amino and the remaining ones are each an aliphatic, araliphatic or aromatic radical, hydrogen, hydroxyl, sulfo or a radical see diagramm : EP0146889,P6,F4 and individual radicals R**2 can be identical or different and are each an aliphatic, araliphatic or aromatic radical, and one radical R**2 may furthermore be hydrogen, and two adjacent radicals R**1 , together with the two adjacent carbon atoms, may furthermore be members of a fused aromatic radical, by hydrogenating an aromatic nitrosulfonic acid in the presence of a hydrogenation catalyst and acids or salts under superatmospheric pressure, wherein an aromatic nitrosulfonic acid of the formula II see diagramm : EP0146889,P6,F5 where the individual radicals R**3 can be identical or different, at least one radical R**3 is nitro and the remaining ones have the same meanings as R**1 , is hydrogenated under a pressure of between 1 and 5 bar, in the presence of Raney nickel and/or Raney cobalt and a) from 1 to 25% by weight of boric acid and/or a borate, and b) from 0.1 to 0.9% by weight of phosphoric acid and/or a phosphate, the percentages being based on starting material II.