ПРОПИОНИТРИЛ

Химические свойства

Propionitrile is a colorless liquid with a pleasant, sweetish, ethereal odor. Propionitrile [107-12-0], ethyl cyanide, CH3CH2CN, is a colorless liquid which is miscible with water, ethanol, dimethylformamide, and diethyl ether. The physical properties are listed in Table 1. Propionitrile is obtained either by hydrogenation of acrylonitrile or by the gas-phase reaction of propanal or propanol with ammonia. It is also obtained as a byproduct in the electrohydrodimerization of acrylonitrile to adiponitrile (EHD process).

Использование

Propionitrile is an intermediate for organic syntheses, e.g. Houben-Hoesch reaction, as well as for pharmaceuticals, e.g. ketoprofen and fragrances.

Методы производства

Propionitnle may be prepared by dehydration of propionamide (or propionic acid plus ammonia) or by distilling ethyl sulfate and concentrated aqueous KCN. It also is formed as a byproduct of the electrohydrodimerization of acrylonitrile or by the hydrogenation of acrylonitrile with the use of copper, rhodium or nickle catalysts . U.S. production is estimated for 1980 to range between 10-15 million pounds.

Определение

ChEBI: A nitrile that is acrylonitrile in which the carbon-carbon double bond has been reduced to a single bond.

Общее описание

A colorless liquid with an ether-like odor. Density 0.683 g / cm3. Flash point 61°F. Toxic by inhalation, skin absorption, and ingestion. Vapors are heavier than air. Used as a solvent, and to make other chemicals.

Реакции воздуха и воды

Highly flammable. Soluble in water.

Профиль реактивности

Propionitrile is incompatible with strong acids, strong bases, strong oxidizing agents and strong reducing agents. After refluxing for 24 hours at 221°F, a mixture of Propionitrile with N-bromosuccinimide exploded.

Опасность

Toxic by ingestion and inhalation. Flammable, dangerous fire risk.

Угроза здоровью

Propionitrile is highly toxic. This super toxic compound has a probable oral lethal dose in humans of less than 5 mg/kg or a taste (less than 7 drops) for a 70 kg (150 lb.) person. It is a mild to moderate skin and eye irritant.

Пожароопасность

When heated to decomposition, Propionitrile emits toxic fumes of nitrogen oxides and cyanide. Propionitrile is a flammable/combustible material and may be ignited by heat, sparks or flames. Vapors may travel to a source of ignition and flash back. Container may explode in heat of fire. Vapor explosion and poison hazard indoors, outdoors or in sewers. Runoff to sewer may create fire or explosion hazard. Generates cyanide ions. Poisonous on contact with acids. stable, but may become unstable at elevated temperatures and pressures.

Промышленное использование

Propionitnle is used as a selective solvent in the chemical industry and in petroleum refining and as a dielectric fluid . It has also been used experimentally as an ulcerogen .

Профиль безопасности

Poison by ingestion, skin contact, intravenous, and intraperitoneal routes. Moderately toxic by inhalation. Experimental teratogenic effects. Other experimental reproductive effects. A skin and eye irritant. Dangerous fire hazard when exposed to heat, flame (sparks), oxidners. Mixture with N- bromosuccinimide may explode when heated. To fight fire, use water spray, foam, mist, CO2, dry chemical. When heated to decomposition it emits toxic fumes of NOx and CN-. Used as a solvent in petroleum refining, and as a raw material for drug manufacture. See also NITRILES.

Возможный контакт

Used as a solvent in petroleum refin- ing, as a chemical intermediate; a raw material for drug manufacture; and a setting agent.

Перевозки

UN2404 Propionitrile, Hazard Class: 3; Labels: 3-Flammable liquid, 6.1-Poisonous material. UN1992 Flammable liquids, toxic, n.o.s., Hazard Class: 3; Labels: 3-Flammable liquid, 6.1-Poisonous materials, Technical Name Required.

Методы очистки

Shake the nitrile with dilute HCl (20%), or with conc HCl until the odour of isonitrile has gone, then wash it with water, and aqueous K2CO3. After a preliminary drying with silica gel or Linde type 4A molecular sieves, it is stirred with CaH2 until hydrogen evolution ceases, then decant and distil from P2O5 (not more than 5g/L, to minimise gel formation). Finally, it is refluxed with, and slowly distilled from CaH2 (5g/L), taking precautions to exclude moisture. [Beilstein 2 IV 728.]

Несовместимости

Incompatible with oxidizers (chlorates, nitrates, peroxides, permanganates, perchlorates, chlo- rine, bromine, fluorine, etc.); contact may cause fires or explosions. Keep away from alkaline materials, strong bases, strong acids, oxoacids, epoxides., reducing agents. Hydrogen cyanide is produced when propionitrile is heated to decomposition. Reacts with acids, steam, warm water; producing toxic and flammable hydrogen cyanide fumes. Nitriles may polymerize in the presence of metals and some metal compounds. They are incompati- ble with acids; mixing nitriles with strong oxidizing acids can lead to extremely violent reactions. Nitriles are generally incompatible with other oxidizing agents such as peroxides and epoxides. The combination of bases and nitriles can produce hydrogen cyanide. Nitriles are hydrolyzed in both aqueous acid and base to give carboxylic acids (or salts of carboxylic acids). These reactions generate heat. Peroxides convert nitriles to amides. Nitriles can react vigorously with reducing agents. Acetonitrile and propionitrile are soluble in water, but nitriles higher than propionitrile have low aqueous solubility. They are also insoluble in aqueous acids .

Утилизация отходов

Alcoholic NaOH followed by calcium hypochlorite may be used, as may incineration . Consult with environmental regulatory agencies for guid- ance on acceptable disposal practices. Generators of waste containing this contaminant (≥100 kg/mo) must conform with EPA regulations governing storage, transportation, treatment, and waste disposal.