Abstract: A process for preparing hydroxylammonium nitrate which comprises reacting a hydroxylammonium salt, e.g., the sulfate, with an aqueous solution of a nitrate salt, e.g., sodium nitrate, in the presence of an organic solvent, e.g., butanol, in which the hydroxylammonium nitrate is soluble and the by-product salts are insoluble.

Abstract: A method of regenerating noble metal catalysyts used for the catalytic reduction of nitrogen oxide with hydrogen, wherein the noble metal catalyst is treated with an aqueous alkaline solution having a pH of more than 9.

Abstract: Solutions of an hydroxylamine or an at least partially neutralized hydroxylamine salt are stabilized against decomposition by adding thereto a water-soluble alkali metal, alkaline earth metal or ammonium thiosulfate.

Abstract: A process for working up aqueous mother liquors containing hydrochloric acid, sulfuric acid and their hydroxylammonium and ammonium salts, entails the mother liquors being intimately mixed with an excess of cyclohexanone based on the content of hydroxylammonium salts, while maintaining a pH of from 3 to 5.5 by adding alkali metal hydroxide solutions, and the cyclohexanone phase which contains cyclohexanone oxime being removed and washed with water until essentially free of chloride.

Abstract: Potassium hexatitanate fibers having a tunnel structure and a free potassium content of 5 ppm or less can be produced by mixing together a titanium containing compound and a potassium containing compound in a ratio represented by the formula K.sub.2 O.nTiO.sub.2 (wherein n=from 2 to 4); firing the mixing at 900.degree. to 1,200.degree. C. to produce mass of potassium titanate fibers; dipping the mass of product in either cold or hot water to disintegrate the mass of potassium titanate fibers into individual single fibers; adding an acid to the slurry to adjust the pH value to 9.3-9.7, thereby changing the composition of the potassium titanate fibers so that the molar ratio of TiO.sub.2 /K.sub.2 O is in the range of from 5.95 to 6.00; heating the fibers at 950.degree. to 1,150.degree. C. for 1 hour to more; and washing the fibers with an acid. The potassium hexatitanate fibers, which have minimal free potassium content, i.e.

Abstract: A process for producing hydroxylammonium salts of hydrogenating nitrogen monoxide in an acidic medium in the presence of a catalyst which is prepared by subjecting a platinum compound to a first reductive treatment with a thiosulfate or a thiosulfate combined with an alkali metal sulfide in the presence of a catalyst carrier, and a second reductive treatment with a reductant selected from the group consisting of formic acid, hydrogen, hydrazine and sodium borohydride at a temperature of 50.degree. C. to 150.degree. C.

Abstract: A process for reducing excess nitric acid in an aqueous hydroxylamine nitrate solution. The process is conducted by reacting the aqueous hydroxylamine nitrate solution with a basic neutralizing agent such as nitric oxide, hydroxylamine vapor or a mixture thereof or by contacting the aqueous hydroxylamine nitrate solution with an anion exchange resin having a pKa in the range of from about 5 to about 9. The aqueous hydroxylamine nitrate solution may be produced by the electrolysis of nitric acid.

Abstract: Hydroxylamine perchlorate or nitrate is prepared by forming an alcohol-hyxylamine solution from reacting a slurry of hydroxylamine sulfate in alcohol with ammonia, reacting perchloric acid or nitric acid therewith to form the desired salt, and separating the salt.

Abstract: Hydroxylamine perchlorate or nitrate is prepared by forming an alcohol-hyxylamine solution from reacting a slurry of hydroxylamine sulfate in alcohol with sodium alkoxide, reacting perchloric acid or nitric and therewith to form the desired salt, and separating the salt.

Abstract: Hydroxylammonium salts are prepared by catalytic reduction of nitrogen monoxide with hydrogen in dilute aqueous mineral acids at elevated temperature in the presence of suspended supported platinum catalysts obtainable by precipitating metallic platinum from aqueous solutions of platinum salts onto carriers suspended therein by means of reducing agents in the presence of one or more water-soluble substituted or unsubstituted thioureas.

Abstract: Hydroxylammonium salts are prepared by catalytic reduction of nitrogen monoxide with hydrogen at elevated temperature in a dilute aqueous solution of a mineral acid in the presence, in suspension, of a supported platinum catalyst obtainable by precipitating metallic platinum from an aqueous platinum solution onto a support by means of a reducing agent in the presence of an organic chelating agent and partially poisoned with sulfur.

Abstract: Aqueous solutions of free hydroxylamine are prepared by a process in which(a) hydroxylammonium sulfate is reacted with ammonia in a lower alkanol as solvent, and a solution of free hydroxylamine and solid ammonium sulfate with residues of hydroxylammonium sulfate is obtained,(b) solid ammonium sulfate and hydroxylammonium sulfate are separated off from the resulting reaction mixture, and an alcoholic solution of free hydroxylamine is obtained as the filtrate,(c) a stabilizer and water are added to the resulting alcoholic solution of free hydroxylamine, and(d) the alkanol is distilled off from the alcoholic solution containing free hydroxylamine, the stabilizer and water.

Abstract: This invention relates to a method for catalyzing the reactionsQZ+H.sub.2 X.fwdarw.QZX (1) psandQZX.fwdarw.QZ+H.sub.2 X (2)wherein Q=C or N;Z=O or S;X=O, S, NH or NR;R=C.sub.1 to C.sub.8 alkyl which may be linear, branched or cyclized,which comprises:contacting at least one polydentate nitrogen-containing chelating agent complexed with a metal atom with the reactants of one of said reactions, wherein said contacting takes place in the presence of a means for oxidizing when reaction (1) is catalyzed and in the presence of a means for reducing when reaction (2) is catalyzed.

Abstract: Wastewaters containing hydroxylamine or its salts are worked up by a process in which the said wastewaters are passed over a strongly acidic ion exchanger, after which a 5-15% strength by weight aqueous sulfuric acid is passed over the said ion exchanger and a solution of hydroxylammonium sulfate in aqueous sulfuric acid is obtained.

Abstract: Solid hydroxylammonium sulfate is reacted with an alcohol solution of an alkali metal hydroxide or alkoxide to produce an alcoholic hydroxylamine liquid phase and a sulfate-containing solid phase. The liquid phase may be used for further reactions such as oxidations, hydroxamic acid production or neutralization to other hydroxylammonium salts. The different bases behave differently with regard to suitable and preferable solvents and temperatures.

Abstract: Noble metal catalyst, in particular platinum catalysts, which are applied on carriers and have become poisoned by metals as a result of being used for many years in the preparation of hydroxyl-ammonium salts by catalytic reduction of nitric oxide with hydrogen in an aqueous mineral acid are regenerated by a process in which the metallic impurities are dissolved using nitric acid or aqua regia, the solution is neutralized, the troublesome metals are precipitated from the neutralized solution by means of a selective precipitating reagent, and the purified platinum solution is reused for the preparation of the catalyst. Organic complexing agents which form insoluble or sparingly soluble complexes with the metallic impurities are preferably used as precipitating reagents.

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

Abstract: Solid hydroxylammonium sulfate is reacted with an alcohol solution of an alkali metal hydroxide or alkoxide to produce an alcoholic hydroxylamine liquid phase and a sulfate-containing solid phase. The liquid phase is further reacted with an acid other than sulfuric acid to form another hydroxylammonium salt. The different bases behave differently with regard to suitable and preferably solvents and temperatures.

Abstract: Solid hydroxylammonium sulfate is reacted with an alcohol solution of an alkali metal hydroxide or alkoxide to produce an alcoholic hydroxylamine liquid phase and a sulfate-containing solid phase. The liquid phase may be used for further reactions such as oxidations, hydroxamic acid production or neutralization to other hydroxylammonium salts. The different bases behave differently with regard to suitable and preferable solvents and temperatures.

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: The invention is a process for electroplating palladium in which at least part of the palladium in the electroplating bath is added as a palladium ammine hydroxide. Both the solid form and solution form of palladium ammine hydroxide are useful in supplying palladium to the palladium electroplating bath. Both solution and crystals are chemically stable and can be stored for long periods of time. Further, use of the palladium ammine hydroxide compounds permit replenishment without accumulation of undesirable ions in the bath and also neutralizes hydrogen ions formed in the plating process.

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: Solid hydroxylammonium sulfate is reacted with an alcohol solution of an alkali metal hydroxide or alkoxide to produce an alcoholic hydroxylamine liquid phase and a sulfate-containing solid phase. The liquid phase is used for further reactions such as oximations and hydroxamic acid production. The different bases behave differently with regard to suitable and preferable solvents and temperatures.

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: The invention is a process for electroplating palladium in which at least part of the palladium in the electroplating bath is added as a palladium ammine hydroxide. Both the solid form of and solution form of palladium ammine hydroxide are useful in supplying palladium to the palladium electroplating bath. Both solution and crystals are chemically stable and can be stored for long periods of time. Further, use of the palladium ammine hydroxide compounds permit replenishment without accumulation of undesirable ions in the bath and also neutralizes hydrogen ions formed in the plating process.

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: A mixture of ketoxime such as methyl ethyl ketone oxime (MEKO), an inorganic acid such as sulfuric acid and optionally water is fed to an intermediate point of a fractional distillation column. Steam is fed to the base of the column and operating conditions are sufficient to produce the corresponding ketone (e.g. methyl ethyl ketone) or its water azeotrope as the overhead product and the corresponding hydroxylammonium salt (e.g. the sulfate) as the bottoms. Crystallization of the salt from the bottoms leaves a mother liquor which may be recycled to a reboiler from which the steam is generated.

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: A process is described for the production of hydroxylamine, or hydroxylamine salts, from the reduction of nitrogen monoxide with hydrogen in an acid liquid reaction medium in one reactor in the presence of a noble-metal catalyst, wherein explosive gaseous mixture compositions are avoided by maintaining the presence of an inert gas at a level of between 10% and 80% by volume, and whereby the process is conducted at elevated pressures of between about 1500 and 5000 kPa.

Abstract: A process for separating hydroxylamine from an aqueous solution containing hydroxylammonium salts in mixture with salts of predominantly monovalent cations whose corresponding free bases have base dissociation constants greater than 10.sup.-7. Said solution is passed through a bed of cation exchange resin loaded predominantly with monovalent cations whereby hydroxylammonium and the other cations in solution substantially displace said cations from the resin. A second aqueous solution containing a monovalent amine or hydroxide base of at least 0.5 molar concentration having a dissociation constant greater than 10.sup.-7 is passed through the resin bed whereby hydroxylamine is preferentially released to the solution and the resin is correspondingly loaded with the cation of said base. Hydroxylammonium salts can be crystallized from the solution after addition of a stoichiometric amount of an appropriate acid.

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: Iridium compounds are produced by refluxing a diammonium hexahalo salt of iridium and sulfamic acid in an aqueous medium for more than thirty hours. When the diammonium hexachloro salt of iridium is used, the iridium product is an olive green salt having a melting point above 350.degree. C. The iridium products are useful as constituents of electroplating baths.

Abstract: A process for obtaining hydroxylammonium salts from aqueous solutions containing hydroxylammonium salts in mixture with ammonium and/or sodium salts. Said solutions are contacted with a water immiscible organic solution containing a cation exchange compound of structure R.sub.1 COOX, or (R.sub.2 O)(R.sub.3 O)POOX, or (R.sub.2 O)PO(OX).sub.2, or mixtures thereof and optionally an additive of structure R.sub.4 R.sub.5 R.sub.6 PO, or (R.sub.4 O)(R.sub.5 O)(R.sub.6 O)PO, or mixtures thereof, wherein R.sub.1 is an alkyl or alkenyl group of from twelve to twenty carbon atoms, R.sub.2 and R.sub.3 are alkyl groups of from six to eighteen carbon atoms, R.sub.4, R.sub.5 and R.sub.6 are alkyl groups of from three to twelve carbon atoms, and X is H, Na or NH.sub.4, whereby hydroxylammonium ions are preferentially extracted from the aqueous phase in exchange for X from the organic phase.

Abstract: A process for pre-treating platinum/palladium catalysts, used in the preparation of hydroxylamine, comprising contacting the same with an aqueous salt solution, inhibits (a) the decomposition of hydroxylamine and (b) the consequent formation of explosive mixtures of N.sub.2 O with hydrogen or hydrocarbons.

Abstract: A process for separating hydroxylamine from an aqueous solution thereof also containing salts of cations whose corresponding free bases have base dissociation constants greater than 10.sup.-7. Said solution is brought to a pH of 6-11 and is passed through a bed of strongly ionic exchange resin loaded with compensating ions whereby hydroxylamine is retained in the gel volume of the resin bed and the ions in solution are substantially excluded from the resin. The ionic salts accordingly move faster through the bed and predominate in a first effluent fraction and the hydroxylamine appears predominantly in a later effluent fraction. Hydroxylammonium salts can be crystallized from the effluent hydroxylamine solution after addition of a stoichiometric amount of an appropriate acid.

Abstract: An improved process is described for the reduction of ammonium ions, while avoiding any increase in nitrate ion concentration, in a liquid stream recycled between a zone of synthesis of hydroxyl ammonium salt and a zone for synthesis of oxime, wherein the liquid stream is contacted with a gas stream consisting essentially of nitrogen monoxide and containing nitrogen dioxide at a pressure above 1 atmosphere, at a temperature of at least 80.degree. C., such that after the contact the molar NO.sub.2 /NO ratio of the gas stream is within the range of between about 10.sup.-1 to 10.sup.-4 :1.

Abstract: An improved process is described for producing hydroxylamine, NH.sub.2 OH, a valuable intermediate in the industrial manufacture of nylon-6, in which hydrogen sulfide is reacted with nitric oxide, or mixtures of nitrogen oxides, in aqueous acidic media containing a solid sulfur-resistant catalyst, such as activated carbon, at ambient temperature and pressure and substantially in the absence of elemental oxygen.An important aspect of the invention is that the industrial waste gases, hydrogen sulfide and nitrogen oxide, can be effectively utilized in the process.

Abstract: A process for preparing activated carbon supported catalysts by mixing an activated carbon support having acid surface groups with an aqueous solution containing one or more cations selected from the groups IB and VIII of the Periodic System of Elements as well as Zn to effect cation exchange with the acid groups on the surface of the activated carbon support, separating the cation exchanged activated carbon. Said exchanged surface cations are thereafter reduced on the carbon support in the medium which is later to be subjected to the catalyzed reaction. The surface of the activated carbon support may be oxidized to increase the number of acid groups per unit area prior to ion exchange.

Abstract: Nitrogen oxides are removed from a flue gas by wet process, where the flue gas is contacted with a solution of transition metal complex compounds capable of reacting with oxygen in the presence of oxygen, thereby forming oxygen complexes, and the nitrogen oxides are oxidized and absorbed by the oxygen complexes.

Abstract: A process for forming hydroxylamine and/or its salt, by reducing nitrogen monoxide, nitric acid, or a nitrate salt and improvements therein, wherein starch, gelatin, polyacrylamide or polyvinyl alcohol is added to the reaction mixture.

Abstract: A process for preparing concentrated solutions of hydroxylammonium nitrate (HAN) or hydroxylammonium perchlorate (HAP) which comprise reacting hydroxylammonium sulfate with either barium nitrate or barium perchlorate, in such a way that the dissolved barium salt is reacted with the dissolving hydroxylammonium sulfate while agitating the system so as to keep the slurried barium salt from directly contacting the hydroxylammonium sulfate. The rate of addition of the hydroxylammonium sulfate is slower than the rate of solution of the barium salt. An excess of barium nitrate or barium perchlorate ions is needed in the solution to which the hydroxylammonium sulfate is added until the reaction is terminated. The concentration of the HAN or HAP in the final solution can be increased still further if a solution of HAN or HAP is respectively used in forming the barium salt slurry.

Abstract: An improved process for preparing a hydroxyl-amine salt by reduction of a solution of nitrate ions or nitrogen monoxide. Dissolved molybdenum in amounts as low as about two milligrams per liter of nitrate/nitrogen monoxide solution are known to interfere with the reduction reaction. The present invention provides a simple method of reducing molybdenum contamination, and hence enhancing the efficiency of the reduction reaction. Dissolved molybdenum is removed from the nitrate/nitrogen monoxide solution by coprecipitation with a complex iron-ammonium phosphate. If chromium is present, it will also be removed by this coprecipitation.

Abstract: In a process for manufacturing a lactam which includes rearranging a cycloalkanone-oxime with sulfuric acid to form the lactam, neutralizing the rearrangement mixture with ammonia to form ammonium sulfate, and separating the lactam and the ammonium sulfate, the improvement which comprises:A. heating at least a portion of the ammonium sulfate to a temperature of 240.degree. - 460.degree. C to form ammonia and ammonium bisulfate;B. separating the ammonia from the ammonium bisulfate;C. recycling the ammonia to neutralize the rearrangement mixture;D. burning the ammonium bisulfate at a temperature of 850.degree. - 1250.degree. C to form an SO.sub.2 -containing gas;E. oxidizing the SO.sub.2 -containing gas to form sulfuric acid; andF. recycling the sulfuric acid to the rearrangement stage.

Abstract: In a process for manufacturing a lactam which includes rearranging a cycloalkanone-oxime with sulfuric acid to form said lactam, neutralizing the rearrangement mixture with ammonia to form ammonium sulfate, and separating said lactam and said ammonium sulfate, the improvement which comprises:A. forming the ammonium sulfate into finely divided particles;B. burning the particles at a temperature of 850.degree. - 1250.degree. C. to form an SO.sub.2 -containing gas;C. oxidizing the SO.sub.2 -containing gas to form sulfuric acid; andD. recycling at least a portion of the sulfuric acid to the cycloalkanone-oxime rearrangement step.No external source of sulfuric acid is required. A portion of the SO.sub.2 -containing gas can be used for the manufacture of hydroxylamine sulfate, in which case no external source of SO.sub.2 need be required.