Patents
Patents for C01B 21 - Nitrogen; Compounds thereof (10,781)
12/1991
12/24/1991US5075091 Process for the preparation of silicon nitride
12/24/1991US5075055 Process for producing a boron nitride crucible
12/24/1991US5074892 Using lithium exchanged type x zeolite
12/24/1991CA1293359C Process for removing oxides of nitrogen and sulfur from waste gases
12/20/1991CA2044909A1 Pressure swing adsorption method for separating gaseous mixtures
12/19/1991WO1991019670A1 Method of forming dinitramide salts
12/19/1991WO1991019669A1 Dinitramide salts and method of making same
12/19/1991CA2064472A1 Method of forming dinitramide salts
12/18/1991EP0461478A1 Improved air separation pressure swing adsorption process
12/17/1991US5073358 Continuous withdrawing nitride product form first fluidized be d and supplying to second fluidized bed for nitriding
12/17/1991US5073193 Method of collecting plasma synthesize ceramic powders
12/17/1991CA1293106C Method of producing silicon nitride powders
12/11/1991EP0460943A1 Boron nitride crucible and its production
12/11/1991EP0460636A2 Improved membrane nitrogen process and system
12/10/1991US5071935 Ammoniolysis of a cyclic triborotriazine, a dichloroazoboron compound and primary amine; heat-resistant crosslinked network; fiber; filaments; efficiency
12/10/1991US5071813 Carbides, nitrides, or carbonitrides of molybdenum, tungsten, iron, cobalt, nickel
12/10/1991US5071450 Pyrolysis of a carbon-containing organic compound to deposit carbon to narrow pare size; selective adsorption
12/07/1991CA2043910A1 Membrane nitrogen process and system
12/04/1991EP0266417B1 Reduction of no x? in flue gas
12/03/1991US5069887 Selective adsorption on zeolite having specified water of crys tallinity
12/03/1991US5069728 Process for heat treating metals in a continuous oven under controlled atmosphere
12/03/1991US5069690 Nitrogen trifluoride from carbon tetrafluoride; hydrothermally treated zeolite
11/1991
11/26/1991US5068037 Solvent extraction with 1-phenyl-3-methyl-4-trifluoroacetylpyrazol-5-one and trioctylphosphine oxide
11/21/1991EP0457059A1 Process for removal of nitrogen oxides producing HNO3
11/20/1991CN1056293A Machine for making pure nitrogen by pressure variation and adsorption
11/19/1991US5066530 Ultraviolet Sunscreen
11/19/1991US5066473 Surface treatment, oxidation
11/13/1991EP0220198B1 Preparing metal compounds by pyrolysis
11/13/1991CA2042464A1 Process for the removing of nitrogen from exhaust gases while obtaining hno3
11/12/1991US5064538 Dialysis and electrodialysis
11/07/1991DE4013205A1 Cooling nitrogen oxide(s)-contg. gas mixt.
11/06/1991CN1014598B Method for preparing polychlorophosphnitrile
11/06/1991CN1014587B Selective adsorption of c02 on zeolites
10/1991
10/31/1991WO1991016266A1 PROCESS AND DEVICE FOR COOLING DOWN A NOx-CONTAINING GASEOUS MIXTURE FROM A NITRIC ACID PRODUCTION PLANT
10/30/1991EP0454622A1 Alkenyl substituted stabilizers
10/30/1991EP0454531A1 Process and apparatus for the preparation of ultra-pure nitrogen
10/30/1991CN1055728A Polymeric hydridosilazane and process for production thereof and from which manufacture of ceramic materials containing silicon nitride and process for production thereof
10/30/1991CN1055716A Ceramic materals containing silicon nitride and process for production theereof
10/30/1991CN1055715A Polymeric hydridothiosilazane and process for production thereof and from which manufacture of ceramic materials containing silicon nitride and process for production thereof
10/29/1991US5061469 Process for producing shaped boron nitride product
10/29/1991US5061416 Infiltrating with liquid, freezing, thawing
10/29/1991US5061298 Gas separating membranes formed from blends of polyimide polymers
10/22/1991US5059578 Thermosetting phenolic resin of specific infrared absorption, polyvinyl alcohol or cellulose binder, molding heat treating
10/21/1991CA2040745A1 Process and device for the production of ultra-pure nitrogen
10/17/1991WO1991015868A1 Process, composition, and apparatus for purifying inert gases to remove lewis acid and oxidant impurities therefrom
10/16/1991EP0451677A2 Vacuum swing adsorption process for production of 95+% N2 from ambient air
10/11/1991CA2039649A1 Vacuum swing adsorption process for production of 95+% n2 from ambient air
10/09/1991EP0450785A1 Air separator
10/09/1991EP0450562A2 Nitride products and method and apparatus for producing nitride products
10/01/1991US5053365 Method for the low temperature preparation of amorphous boron nitride using alkali metal and haloborazines
10/01/1991CA1289976C Method of production of ceramic powders and powders thus obtained
09/1991
09/24/1991US5051143 Alkali metal azide, alkali metal perchlorate oxidizer
09/24/1991US5051115 Pressure swing adsorption process
09/24/1991CA2037985A1 Economical air separator
09/22/1991WO1991014655A1 Process for the treatment of an aqueous solution containing mainly nitric and hydrofluoric acids
09/19/1991WO1991013679A1 Bulk gas sorption composition and apparatus
09/18/1991EP0447388A1 Procedure for manufacturing of finegrain, sinteractive nitride- and carbonitride-powders of titanium
09/18/1991CN1013962B Process for recovery of platinum catalyst
09/17/1991US5049529 Conversion of polycarbosilanes into silicon carbonitride ceramics
09/17/1991US5049367 Aluminum nitride powder and process for preparation of the same
09/12/1991DE4107191A1 Iridium catalyst for hydrazinolysis - prepd. on aluminium oxide carrier of large surface area
09/11/1991CN1054402A Low temp. purification of gases
09/11/1991CN1013881B Production of controllable atmosphere of nitrogen contg. co
09/05/1991WO1991013044A1 Chromium-based nitrified baked material and method of obtaining it
09/04/1991CN1054232A End purifying device suitable for n (a, he) and refining route
08/1991
08/29/1991DE4027404A1 Nitric oxide oxidn. in gas stream by scrubbing with nitric acid - contg. nitrous acid by desorbing of acid cpds. into gas and replacing nitrous acid
08/28/1991CN1013662B Method for preparation polychlorophosphnitrile under bis (dichlor-phosphoryl) imide
08/28/1991CN1013661B Process for n-(dichloro-phosphate-acyl)-trichloro-phosphate-nitrile
08/28/1991CN1013660B Process for producing n-(dichloro-phosphoryl) trichlorophosphazene from phosphorus pentachloride and ammonium chloride
08/28/1991CN1013659B Method and facility for producing silicon nitride powder
08/28/1991CN1013658B Method for purification nitrogen for refining aluminium fusant
08/27/1991US5043219 Composite material
08/21/1991EP0442032A1 Process for preparing silicon nitride
08/21/1991EP0442013A1 Isocyanate- and isothiocyanate-modified polysilazane ceramic precursors
08/21/1991CN2083147U Novel ammonia seperator
08/20/1991US5041276 Ammonia oxidation
08/15/1991CA2024139A1 Silicon nitride vacuum furnace process
08/14/1991EP0440604A1 Devices and method for cleaning gases.
08/13/1991US5039502 Dissolving metals in nitric acid containing nitrous acid-forming additive; inhibition of ammonium nitrate formation
08/07/1991EP0440235A2 Preparation of silicon nitride powder
08/07/1991EP0439845A2 Alpha-omega chlorosilazanes and a method for their preparation
08/06/1991US5037624 Composition, apparatus, and process, for sorption of gaseous compounds of group II-VII elements
08/06/1991CA1287433C Preceramic polymers derived from cyclic silazanes, and halosilanes anda method for their preparation
08/06/1991CA1287432C Preceramic polymers derived from cyclic silazanes and halogenated disilanes and a method for their preparation
07/1991
07/30/1991US5035775 Ultrapure hydrazine production
07/28/1991CA2034953A1 .alpha.,w-chlorosilazanes, and a process for their preparation
07/25/1991WO1991010629A1 Process for using dross residues to produce refractory products
07/25/1991DE4100532A1 Impure nitric acid treatment - by addn. to phosphoric acid and recovery by distn. or in reduced form
07/24/1991EP0438282A1 Production of pure nitrogen from air
07/24/1991EP0438036A2 Method for determining the end of useful life of an inert gas purifier and apparatus therefor
07/24/1991EP0437824A1 Process for the preparation of nitrosylsulfuric acid
07/20/1991CA2034597A1 Low temperature purification of gases
07/16/1991US5032370 Method of preparing silicon nitride with a high alpha-phase content
07/16/1991US5032152 Modified molecular sieve
07/10/1991CN1052874A Boron-nitrogen polymer, method of production and uses as boron nitride precursor
07/09/1991US5030434 Silicon nitride powders with improved surface properties and processes for their preparation
07/02/1991US5028571 Conversion of polycarbosilanes into silicon nitride ceramics
06/1991
06/27/1991WO1991008983A1 Process for producing aqueous ammonium nitrite solutions and use of these solutions as volatile corrosion inhibitors
06/27/1991WO1991008982A1 Catalyst pack support in ammonia oxidation burner
06/27/1991DE3942065A1 Verfahren zur herstellung waessriger ammoniumnitritloesungen und verwendung dieser loesungen als fluechtiger korrosionsinhibitor Process for preparing aqueous ammonium nitrite loesungen and use this loesungen as volatile corrosion inhibitor
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