Ammonia gaseous

Sodamide. This substance is prepared by the reaction between gaseous ammonia and molten sodium ... 

The Biazzi continuous process is also used. The reactants are continuously fed to a series of nitrators at 15—20°C followed by separation of the PETN, water washing, solution in acetone at 50°C, neutralization with gaseous ammonia, and precipitation by dilution with water. The overall yield is more than 95%. The acetone and the spent acid are readily recovered. 

Ammonia—Gas-Cured Flame Retardants. The first flame-retardant process based on curing with ammonia gas, ie, THPC—amide—NH, consisted of padding cotton with a solution containing THPC, TMM, and urea. The fabric was dried and then cured with either gaseous ammonia or ammonium hydroxide (96). There was Httle or no reaction with cellulose. A very stable polymer was deposited in situ in the cellulose matrix. Because the fire-retardant finish did not actually react with the cellulose matrix, there was generally Httle loss in fabric strength. However, the finish was very effective and quite durable to laundering. 

Silver fluoride forms explosive adducts with ammonia (qv) (5,6), and therefore all of the reactions involving Hquid or gaseous ammonia should be carried out with extreme precautions. 

After apphcation to the fabric, the compounds are polymerized by reaction with gaseous ammonia (11,12), then oxidized to phosphine oxides by reaction with hydrogen peroxide. The stmcture of the polymer is shown (13). 

Heating metallic lithium in a stream of gaseous ammonia gives lithium amide [7782-89-0] LiNH2, which may also be prepared from Hquid ammonia and lithium in the presence of platinum black. Amides of the alkaH metals can be prepared by double-decomposition reactions in Hquid ammonia. For example... 

The gaseous ammonia is passed through electrostatic precipitators for particulate removal and mixed with the cooled gas stream. The combined stream flows to the ammonia absorber where the ammonia is recovered by reaction with a dilute solution of sulfuric acid to form ammonium sulfate. Ammonium sulfate precipitates as small crystals after the solution becomes saturated and is withdrawn as a slurry. The slurry is further processed in centrifuge faciHties for recovery. Crystal size can be increased by employing one of two processes (99), either low differential controUed crystallization or mechanical size enlargement by continuous compacting and granulation. 

Chevron s WWT (wastewater treatment) process treats refinery sour water for reuse, producing ammonia and hydrogen sulfide [7783-06-04] as by-products (100). Degassed sour water is fed to the first of two strippers. Here hydrogen sulfide is stripped overhead while water and ammonia flow out the column bottoms. The bottoms from the first stripper is fed to the second stripper which produces ammonia as the overhead product. The gaseous ammonia is next treated for hydrogen sulfide and water removal, compressed, and further purified. Ammonia recovery options include anhydrous Hquid ammonia, aqueous Hquid ammonia, and ammonia vapor for incineration. There are more than 20 reported units in operation, the aimual production of ammonia from this process is about 200,000 t. 

Ammonium bicarbonate, sp gr 1.586, formula wt 79.06, is the only compound in the NH —CO2—H2O system that dissolves in water without decomposition. SolubiUty in 100 g of H2O ranges from 11.9 g at 0°C to 59.2 g/100 g of H2O at 60°C (8). The heat of formation from gaseous ammonia and carbon dioxide andUquid water is 126.5 kj/mol (30.2 kcal/mol). Ammonium bicarbonate is manufactured by passing carbon dioxide gas... 

The heat of formation of ammonium chloride from the elements is 317 kJ /mol (75.8 kcal/mol) it is 175 kJ /mol (41.9 kcal/mol) from gaseous ammonia and gaseous hydrogen chloride. The heat of formation of ammonium bromide from the elements, bromine in the Hquid form, is 273 kJ /mol (65.3 kcal/mol) for ammonium iodide, the corresponding heat of formation is 206 kJ /mol (49.3 kcal/mol). Iodine is in the soHd state. 

Reaction of a P-ketoestei witii gaseous ammonia (/) gives an enamine, which on treatment with methylhydiazine (2) yields an 85 15 mistuie of 3-hydioxy- and 5-hydioxy-l-substituted pyrazoles (36) (eq. 5). Previously P-ketoesters furnished mainly the 5-hydroxy isomer. 

Tin does not react directly with nitrogen, hydrogen, carbon dioxide, or gaseous ammonia. Sulfur dioxide, when moist, attacks tin. Chlorine, bromine, and iodine readily react with tin with fluorine, the action is slow at room temperature. The halogen acids attack tin, particularly when hot and concentrated. Hot sulfuric acid dissolves tin, especially in the presence of oxidizers. Although cold nitric acid attacks tin only slowly, hot concentrated nitric acid converts it to an insoluble hydrated stannic oxide. Sulfurous, chlorosulfuric, and pyrosulfiiric acids react rapidly with tin. Phosphoric acid dissolves tin less readily than the other mineral acids. Organic acids such as lactic, citric, tartaric, and oxaUc attack tin slowly in the presence of air or oxidizing substances. 

Zirconium tetraiodide is the least thermally stable zirconium tetrahaUde. At 1400°C, it disproportionates to Zr metal and iodine vapor. This behavior is utilized in the van Arkel-de Boer process to refine zirconium. As with the tetrachloride and tetrabromide, the tetraiodide forms additional adducts with gaseous ammonia which, upon heating, decompose through several steps ending with zirconium nitride. 

In a typical process adiponitrile is formed by the interaction of adipic acid and gaseous ammonia in the presence of a boron phosphate catalyst at 305-350°C. The adiponitrile is purified and then subjected to continuous hydrogenation at 130°C and 4000 Ibf/in (28 MPa) pressure in the presence of excess ammonia and a cobalt catalyst. By-products such as hexamethyleneimine are formed but the quantity produced is minimized by the use of excess ammonia. Pure hexamethylenediamine (boiling point 90-92°C at 14mmHg pressure, melting point 39°C) is obtained by distillation, Hexamethylenediamine is also prepared commercially from butadience. The butadiene feedstock is of relatively low cost but it does use substantial quantities of hydrogen cyanide. The process developed by Du Pont may be given schematically as ... 

Electrolysis of dilute solutions of hydrogen cyanide in ammonium bromide to give cyanogen bromide. This is then dissolved in a solvent such as tetrahydrofuran and reacted with gaseous ammonia to produce cyanamide. The cyanamide is then heated in an autoclave at about 190-200°C in the presence of ammonia and the melamine, recovered by filtration. 

It is convenient to pass gaseous ammonia into the ethanol. It is advisable to carry out the preparation and manipulation of the ammonia solution in a hood. 

Treatment of ammoniabearing waste from chemical industry Liberation of gaseous ammonia Ammonium chloride Nitric acid... 

Category 1. Relea.se of gaseous ammonia primarily from failure of Tank DK-101 by three plant-damage statc.s overpressure, underpressure and seismic load. For all three it was assumed that ... 

All gaseous ammonia in the tank at rupture escapes. This amount depends on the liquid depth, H. 

F) 2-(n)-Propyl-lsonicotinamide The 30 grams of the ester just obtained are treated with 40 cc of concentrated ammonia saturated with gaseous ammonia. 20 grams of product, having a melting point of 135°C, are obtained. 

The compound 2-amino-2, 6 -propionoxylidide was synthesized by saturating with gaseous ammonia at room temperature a suspension of 50 g (0.195 mol) of 2-bromo-2, 6 -propion-oxylidide in a mixture of 500 ml of 95% alcohol and 400 ml of concentrated aqueous ammonia. The saturation was carried out under mechanical stirring. After 25 hours the mixture was resaturated with ammonia gas. The stirring at room temperature was continued for a total period of 116 hours, and a sample was taken at that time. Gas chromatographic analysis indicated that about 95% of the bromo compound had been converted to the desired product. 

Uchino and Azuma [498] proposed a way in which to recycle the filtrate solutions. The process consists of adding calcium hydroxide, Ca(OH)2, to the filtrate, yielding a calcium fluoride, CaF2 precipitate and gaseous ammonia, NH3. The fluorine and ammonia are recovered in forms that are suitable for reutilization. 

The decomposition described in Equation (146) takes place at relatively low temperatures hence, thermal treatment at a relatively slow temperature rate can be sufficient in order to significantly reduce fluorine levels in the final oxides. Nevertheless, treatment at a high temperature rate can lead to another mechanism of ammonium fluoride decomposition yielding gaseous ammonia and molten ammonium hydrofluoride according to the following scheme ... 

At temperatures above 45°C, however, (NRj MOs compounds decompose yielding gaseous ammonia, NH3, and oxygen as well as tantalum or niobium oxides ... 

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