Nitric Oxide, one of specialty gases is created as a pollutant by the combustion of fossil fuels that are close to excess oxygen. It is also generated by the direct reaction of atmospheric nitrogen and to oxygen during electrical storms. For commercial use, all high-purity Nitric Oxide is obtained from the oxidation of ammonia with a platinum catalyst and heat. Small amounts of NO can be created in the laboratory by reducing diluted nitric acid with copper.
The bulk of the Nitric Oxide created is used as an intermediate in the formulation of concentrated nitric acid. High-purity Nitric Oxide is used in calibration standards for environmental emission oversight, industrial hygiene monitors, and trace impurity analyzers. NO is also introduced into gas mixtures to treat pulmonary arterial hypertension and is finding increasing use as well in many pharmacological research applications in which vasodilation acts as a means of pain reduction.
