Methane hydrogen cyanide from

In one patent (31), a filtered, heated mixture of air, methane, and ammonia ia a volume ratio of 5 1 1 was passed over a 90% platinum—10% rhodium gauze catalyst at 200 kPa (2 atm). The unreacted ammonia was absorbed from the off-gas ia a phosphate solution that was subsequently stripped and refined to 90% ammonia—10% water and recycled to the converter. The yield of hydrogen cyanide from ammonia was about 80%. On the basis of these data, the converter off-gas mol % composition can be estimated nitrogen, 49.9% water, 21.7% hydrogen, 13.5% hydrogen cyanide, 8.1% carbon monoxide, 3.7% carbon dioxide, 0.2% methane, 0.6% and ammonia, 2.3%. 

Emissions to the atmosphere from ammonia plants include sulfur dioxide (SOj), nitrogen oxides (NOJ, carbon monoxide (CO), carbon dioxide (COj), hydrogen sulfide (HjS), volatile organic compounds (VOCs), particulate matter, methane, hydrogen cyanide, and ammonia. The two primary sources of pollutants, with typical reported values, in kilograms per ton (kg/t) for the important pollutants, are as follows ... 

Ponton [60] discusses exemplarily a miniplant concept for performing the Andrussov process, yielding hydrogen cyanide from methane, oxygen and ammonia with a platinum catalyst. HCN is a widely used but highly toxic chemical which requires extreme safety issues, in particular when it is transported or shipped. A miniplant should allow one to produce this toxic material from comparably low toxic ammonia and methane directly on-site at the customer and on-demand in small or even bigger quantities. 

Metal wires and screens are used as fixed-bed catalysts in which reactants are passed through the openings in the gauze, the size of which is defined by the mesh and wire diameter (see Fig. 10A). Gauzes composed of an alloy of platinum and rhodium catalyze the air oxidation of ammonia to nitric oxide, which is subsequently converted to nitric acid, and the production of hydrogen cyanide from ammonia, air, and methane. Formaldehyde production by... 

Production of Hydrogen Cyanide from Methane in a Nitrogen Plasma Jet... 

The Degussa BMA (Blausaure-Methan-Ammoniak, or hydrocyanic acid-methane-ammonia) process also is used in the production of hydrogen cyanide from methane. The difference between the Andrussow process and the Degussa process is that the latter does not use air in the synthesis of hydrogen cyanide. The reaction is as follows ... 

Hydrogen Cyanide from Ammonia and Natural Gas. In the general discussion of the reaction of ammonia with hydrocarbons, reference was made to the s mthesis of HCN from ammonia, methane (natural gas), and air. The over-all reaction CHi + NHj 1.50 —>HCN -t- 3H 0 can be... 

The production of hydrogen cyanide from methane and nitrogen can be presented as process (9-16) assuming a = 2. Plasma-chemical HCN production is an endothermic process ... 

This reaction was first reported by Andmssov (Andrussow) in 1927. It is primarily an industrial process used to manufacture hydrogen cyanide from methane, ammonia, and oxygen over a catalyst of 90% Pt-10% Rh in the form of a pad of woven screens at 1050-1100° C and 2 atm. Therefore, this reaction is known as Andrussow process. In this process, the catalytic gauze is 3-5 mm thick, and when the high gas velocities are employed, the contact times achieved are of the order of a few milliseconds. The effluent stream contains about 8% HCN and a number of byproducts such as hydrogen, CO, and C02. It was reported that in 1978 the output of hydrogen cyanide exceeded 600 million pounds in the United States alone. ... 

Production of hydrogen cyanide from methane is also possible using two process alternatives. The strongly endothermic BMA process (the name originates from the German Blausdure aus Methan und Ammoniak," 1200-1300 °C, Pt contact)... 

Amm oxida tion, a vapor-phase reaction of hydrocarbon with ammonia and oxygen (air) (eq. 2), can be used to produce hydrogen cyanide (HCN), acrylonitrile, acetonitrile (as a by-product of acrylonitrile manufacture), methacrylonitrile, hen onitrile, and toluinitnles from methane, propylene, butylene, toluene, and xylenes, respectively (4). 

In the BMA process, methane (natural gas) and ammonia are reacted without air being present (44). The reaction is carried out in tubes that are heated externally to supply the endothermic heat of reaction very similar to a reformer. Yield from ammonia and methane is above 90%. The off-gas from the converter contains more than 20 mol % hydrogen cyanide, about 70 mol % hydrogen, 3 mol % ammonia, 1 mol % methane, and about 1 mol % nitrogen from ammonia decomposition. 

Poisonous hydrogen cyanide (HCN) is an important industrial chemical. It is produced from methane (CHq), ammonia, and molecular oxygen. The reaction also produces water. An industrial manufacturer wants to convert 175 kg of methane into HCN. How much molecular oxygen will be required for this synthesis ... 

Write the unbalanced form of the equation from the information given, namely methane, ammonia, and molecular oxygen react to form hydrogen cyanide and water ... 

As already mentioned, hydrogen cyanide is formed in simulation experiments using reducing primeval atmospheres. CN was discovered in interstellar space as early as 1940 by optical spectroscopy (Breuer, 1974), and later HCN itself (from measurements using millimetre wavelengths). Only a few years after the Miller-Urey experiments, Kotake et al. (1956) obtained HCN in good yields by reacting methane with ammonia over aluminium-silicate contacts ... 

Hydrogen cyanide (Table 15.1) is a colorless, flammable liquid or gas that boils at 25.7°C and freezes at minus 13.2°C. The gas rarely occurs in nature, is lighter than air, and diffuses rapidly. It is usually prepared commercially from ammonia and methane at elevated temperatures with a platinum catalyst. It is miscible with water and alcohol, but is only slightly soluble in ether. In water, HCN is a weak acid with the ratio of HCN to CN about 100 at pH 7.2, 10 at pH 8.2, and 1 at pH 9.2. HCN can dissociate into H+ and CN. Cyanide ion, or free cyanide ion, refers to the anion CN derived from hydrocyanic acid in solution, in equilibrium with simple or complexed cyanide molecules. Cyanide ions resemble halide ions in several ways and are sometimes referred to as pseudohalide ions. For example, silver cyanide is almost insoluble in water, as are silver halides. Cyanide ions also form stable complexes with many metals. 

Hydrogen cyanide is a highly poisonous gas. It is produced from methane and ammonia. 

Hydrogen cyanide cun be prepared from a mixture of NH-,. methane, and air by partial combustion in the presence of a platinum catalyst ... 

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