Manufacture of hydroxylammonium salts

摘要

Hydroxylammonium salts are manufactured by a process comprising the catalytic reduction of nitric oxide with hydrogen in a dilute aqueous mineral acid in the presence of a suspended platinum catalyst at an elevated temperature, wherein the reaction is carried out in vessels of which the walls consist essentially of conventional copper-free molybdenum-containing austenitic chromium-nickel steels which contain from 16 to 28% by weight of chromium, from 10 to 50% by weight of nickel, from 1 to 4% by weight of molybdenum and at most 0.05% by weight of carbon, together with at least 0.05% by weight of nitrogen up to 0.5% by weight.