Nitric oxide construction materials

Reaction with construction materials, e.g. nitric acid can produce nitric oxide gas on contact with copper in pipes or copper windings in motors of canned pumps ... 

H. Corrosion resistant materials of construction would be specified, but external corrosion is possible due to nitric oxide fumes, allow minimum factor = 0.1. 

CHEMICAL PROPERTIES noncombustible liquid hydrolyzes in water to form hydrochloric acid and phosphoric acid highly corrosive corrodes most common construction materials reacts with chemically active metals such as sodium, potassium and aluminum reacts vigorously with strong nitric acid strong oxidizer FP (NA) LFLZUFL(NA) AT (NA) HC (NA) HF (-319.7 kJ/mol liquid at 25°C) H 7.1 kJ/mol at 161K). 

The CAPROPOL and BASF processes are quite similar. The primary difference is in the materials of construction used for certain equipment and the hydrogenation catalyst in the nitric oxide reduction step. The BASF process utilizes platinum, whereas the CAPROPOL process makes use of palladium catalyst. In both cases, the noble metal catalyst is supported on carbon suspended in dilute sulfuric acid solution. 

In order to get uniformity for the determination and verification of test results for photocatalytic construction materials, it is essential to define performance-based attributes and test methods. This chapter summarizes the current state-of-the-art on the existing standards, and shows an example for a performance-based procedure which covers the removal of nitric oxides (NO ). 

Vapor-phase nitration of paraffin hydrocarbons, particularly propane, can be brought about by uncatalyzed contact between a large excess of hydrocarbon and nitric acid vapor at around 400°C, followed by quenching. A multiplicity of nitrated and oxidized products results from nitrating propane nitromethane, nitroethane, nitropropanes, and carbon dioxide all appear, but yields of useful products are fair. Materials of construction must be very oxidation-resistant and are usually of ceramic-lined steel. The nitroparaffins have found limited use as fuels for race cars, submarines, and model airplanes. Their reduction products, the amines, and other hydroxyl compounds resulting from aldol condensations have made a great many new aliphatic syntheses possible because of their ready reactivity. 

Absorption trains of early ammonia oxidation processes to nitric acid were constructed of chemical stoneware or acid-proof brick, which restricted acid production to near ambient atmospheric pressure because of the low strength of the structural materials. The discovery that Duriron (silicon-iron) or high chrome stainless steels could tolerate these corrosive conditions well allowed the adoption of pressure absorption. This measure markedly decreased the size of the absorbers required and reduced nitrogen oxide stack losses. Pressure operation was easiest to achieve by compression of the feed gases at the front end of the process. In this way improved acid production is obtained at comparable capital costs per unit of product by operation at atmospheric pressure. 

Aluminium is a silver-white metal which is very light it is a good conductor of heat and electricity, malleable (easily beaten or rolled into sheets) and ductile (readily stretched) and of a high tensile strength. The metal slowly oxidizes in moist air, a thin protective film of oxide being formed. It is attacked by dilute hydrochloric acid, concentrated sulphuric acid, sodium hydroxide, potassium hydroxide, and brine, but is almost unattacked by nitric acid in all concentrations. Its alloys with copper are called aluminium bronzes. Its many uses as a material of construction, as the metal or its alloys, include hoppers, drums, ventilation hoods, and ducting, utensils, and electric conductors. 

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