Abstract: Aqueous solutions of hydroxylamine are prepared from aqueous hydroxylammonium salt solutions by electrodialysis by a method in which the aqueous hydroxylammonium salt solution is fed into the middle zone of an electrolysis cell, which is divided into a cathode zone, an anode zone and a middle zone by means of semipermeable membranes, and is electrolyzed, and the catholyte used is an alkali metal hydroxide solution containing ammonia and/or amines.

Abstract: Stabilized solutions of hydroxylamine or its salts in water or alcohols, containing the lactone of the formula ##STR1## and their preparation.

Abstract: Stabilized solutions of hydroxylamine or its salts in water or alcohols, containing 8-hydroxyquinaldines, and their preparation.

Abstract: Aqueous solutions of hydroxylammonium carbonate are prepared from aqueous hydroxylammonium salt solutions by electrodialysis by a method in which the aqueous hydroxylammonium salt solution is fed into the middle zone of an electrolysis cell, which is divided into a cathode zone, an anode zone and a middle zone by means of semipermeable membranes, and is electrolyzed, and the catholyte used is an aqueous solution of an ammonium carbonate or an alkali metal carbonate or of one of the corresponding bicarbonates.

Abstract: Stabilized solutions of hydroxylamine or its salts in water or alcohols, containing hydroxyanthraquinones, and their preparation.

Abstract: Stabilized solutions of hydroxylamine or its salts, containing anthocyans of the formula ##STR1## where R.sup.1, R.sup.2, R.sup.3 and R.sup.4 are each hydrogen, hydroxyl or C.sub.1 -C.sub.4 -alkoxy and X is an anion of a strong mineral acid, and their preparation.

Abstract: Nitrous oxide is removed from gases containing hydrogen, nitric oxide and nitrous oxide by a process in which the gases are treated with molecular sieves.

Abstract: 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 of conventional copper-containing austenitic chromium-nickel steels which contain from 16 to 28% by weight of chromium, from 32 to 50% by weight of nickel, from 1 to 4% by weight of molybdenum, up to 4% by weight of copper and at most 0.1% by weight of carbon and which in addition contain an amount of titanium which is at least 5 times the amount of carbon but is not more than 1% by weight, or an amount of niobium or tantalum which is at least 8 times the amount of carbon but is not more than 1.5% by weight.

Abstract: An improved process for the continuous preparation of hydroxylammonium salts by catalytic reduction of nitric oxide with hydrogen in a dilute aqueous solution of a mineral acid in the presence of a suspended noble metal catalyst at an elevated temperature in several reaction zones connected in series, wherein the improvement comprises maintaining a pH of <2.0 in the last reaction zone.

Abstract: Hydroxylammonium salts are prepared by an improved process, wherein nitric oxide is reduced catalytically with hydrogen in a dilute aqueous solution of a mineral acid in the presence of a suspended supported platinum catalyst and at elevated temperatures, and wherein the improvement comprises avoiding the formation of foam at the surface of the reaction mixture.

Abstract: 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.

Abstract: A process for the preparation of hydroxylammonium salts by catalytic reduction of nitric oxide with hydrogen in a dilute aqueous solution of a mineral acid, in the presence of a suspended supported platinum catalyst, at elevated temperatures, wherein the reaction is carried out in a conventional manner, in one or more reaction zones, under superatmospheric pressure, and the exit gases produced are let down to a lower pressure, and are reacted, in a downstream reaction zone, with the reaction mixture, containing hydroxylammonium salt, the ammonium salt, the supported platinum catalyst and residual mineral acid, from the upstream reaction zone or zones, or with a fresh aqueous solution of the mineral acid, which contains the supported platinum catalyst in suspension.

Abstract: A process for removing nitrous oxide from exit gases which contain this compound and have been obtained in the preparation of hydroxylammonium salts by catalytic reduction of nitric oxide with hydrogen in an aqueous solution of a mineral acid, in the presence of a suspended noble metal catalyst, wherein the exit gases are washed with water.

Abstract: 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 of conventional copper-free molybdenum-containing austenitic chromium-nickel steels which contain from 16 to 28% by weight of chromium, from 20 to 50% by weight of nickel, from 1 to 4% by weight of molybdenum and at most 0.1% by weight of carbon and which in addition contain an amount of titanium which is at least 5 times the amount of carbon but is not more than 1.0% by weight, or an amount of niobium or tantalum which is at least 8 times the amount of carbon but is not more than 1.5% by weight.

Abstract: Hydroxylammonium salts are manufactured by a process comprising the catalytic reduction of nitric oxide with hydrogen in a dilute aqueous solution of a mineral acid in the presence of a suspended platinum catalyst at an elevated temperature, wherein the reaction mixture is recycled and the gas mixture, containing nitric oxide and hydrogen, present in the gas space above the reaction zone, is introduced, by means of one or more downwardly directed jets of liquid, consisting of the recycled reaction mixture and issuing from a nozzle orifice, into one or more circulation zones which are present in the reaction zone, are open at both sides, extend in the direction of the entering jet of liquid and are completely covered by the reaction mixture, the reaction mixture leaving the bottom of the circulation zone and containing unconverted gases is deflected, passed upwards in the annular zone externally surrounding the circulation zone, and at the same time reaction mixture of low gas content is recycled from a separa

Abstract: An improved process for the manufacture of cyclohexanone oxime by reacting cyclohexanone with an aqueous hydroxylammonium-ammonium sulfate solution at temperatures above the melting point of cyclohexanone oxime by the countercurrent process, the improvement consisting in that the reaction is carried out in the absence of solvents and neutralizing and/or buffer salts at pHs of up to 0.5 until equilibrium is reached, the oximes resulting during the reaction being separated from the aqueous phase and the aqueous phase being extracted with cyclohexanone and then subjected to steam distillation.