Hydrazine breaks down in the cell to form nitrogen and hydrogen which bonds with oxygen, releasing water. Hydrazine has a higher electromotive force of 1.56 V compared to 1.23 V for hydrogen. By then flushing the tank with warm water, the liquid hydrazine hydrate is released. By storing the hydrazine in a tank full of a double-bonded carbon- oxygen carbonyl, the fuel reacts and forms a safe solid called hydrazone. Because the fuel is liquid at room temperature, it can be handled and stored more easily than hydrogen. The chief benefit of using hydrazine is that it can produce over 200 m W/cm 2 more than a similar hydrogen cell without requiring (expensive) platinum catalysts. The Italian catalyst manufacturer Acta (chemical company) has proposed using hydrazine as an alternative to hydrogen in fuel cells. Hydrazine compounds can be effective as active ingredients in insecticides, miticides, nematicides, fungicides, antiviral agents, attractants, herbicides, or plant growth regulators. Examples of commercialized bioactive hydrazine derivatives include cefazolin, rizatriptan, anastrozole, fluconazole, metazachlor, metamitron, metribuzin, paclobutrazol, diclobutrazole, propiconazole, hydrazine sulfate, diimide, triadimefon, and dibenzoylhydrazine. Often these applications involve conversion of hydrazine to heterocyclic rings such as pyrazoles and pyridazines. Hydrazine is a precursor to several pharmaceuticals and pesticides. Precursor to pesticides and pharmaceuticals Fluconazole, synthesized using hydrazine, is an antifungal medication. The F-16 fighter jet, Eurofighter Typhoon, Space Shuttle, and U-2 spy plane use hydrazine to fuel their Emergency Start System in the event of an engine stall. Hydrazine is also used as a long-term storable propellant on board space vehicles, such as the Dawn mission to Ceres and Vesta, and to both reduce the concentration of dissolved oxygen in and control pH of water used in large industrial boilers. In a related application, sodium azide, the gas-forming agent in air bags, is produced from hydrazine by reaction with sodium nitrite. Specific compounds include azodicarbonamide and azobisisobutyronitrile, which produce 100–200 mL of gas per gram of precursor. ![]() The largest use of hydrazine is as a precursor to blowing agents. ![]() The nomenclature is a bi-valent form, with prefix hydr- used to indicate the presence of hydrogen atoms and suffix beginning with -az-, from azote, the French word for nitrogen.Īpplications Gas producers and propellants Hydrazines refer to a class of organic substances derived by replacing one or more hydrogen atoms in hydrazine by an organic group. ![]() Īs of 2000, approximately 120,000 tons of hydrazine hydrate (corresponding to a 64% solution of hydrazine in water by weight) were manufactured worldwide per year. Hydrazine is used within both nuclear and conventional electrical power plant steam cycles as an oxygen scavenger to control concentrations of dissolved oxygen in an effort to reduce corrosion. Additionally, hydrazine is used in various rocket fuels and to prepare the gas precursors used in air bags. Hydrazine is mainly used as a foaming agent in preparing polymer foams, but applications also include its uses as a precursor to pharmaceuticals and agrochemicals, as well as a long-term storable propellant for in- space spacecraft propulsion. Hydrazine is highly toxic unless handled in solution as, for example, hydrazine hydrate ( N 2H 4 It is a simple pnictogen hydride, and is a colourless flammable liquid with an ammonia-like odour. Hydrazine is an inorganic compound with the chemical formula N 2 H 4.
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