WHAT IS CYANOMETHANE
cyanomethane, more commonly known as Acetonitrile is a clear, colourless liquid with a sweet, ether like odour which has the chemical formula CH3CN. It is a by-product of acrylonitrile manufacture and it may also be formed by the combustion of wood and vegetation. Tobacco smoke contains acetonitrile and burning polyurethane foam releases acetonitrile and hydrogen cyanide. Acetonitrile is a volatile, highly polar solvent used to extract fatty acids and animal and vegetable oils. It is used in the petrochemical industry in extractive distillation based on its selective miscibility with organic compounds. It is used as a solvent for spinning synthetic fibres and in casting and moulding plastics. In laboratories, it is widely used in high-performance liquid chromatographic (HPLC) analysis and as a solvent for DNA synthesis and peptide sequencing.
PROPERTIES OF CYANOMETHANE
- IUPAC Name: Acetonitrile;
- Other Names: methyl cyanide; cyanomethane; ethyl nitrile; ethanenitrile; methanecarbonitrile
- Formula: C2H3N
- CAS No: 75–05–8
- EINECS: 200–835–2
- Mol Wt: 41.05
- Purity: 99+%
- Appearance: colourless liquid
- Melting Point: –45oC
- Boiling Point: 82oC
- Flash Point: 5.6oC (open cup)
- Flash Point: 12.8oC (closed cup)
- Density: 0.787 g/cm3
- Viscosity: 0.369 @ 25C
- solubility: miscible with water
- Acidity pKa: 25
- Vapour pressure: 72.8 mm Hg @20C
- Refractive index: 1.344
- Vapour density: 1.41
- Explosive linits in air: lower 4.4% Higher 16%
Acetonitrile is completely soluble in water and readily miscible with ethanol, ether, acetone, chloroform, carbon tetrachloride and ethylene chloride. It is immiscible with many saturated hydrocarbons (petroleum fractions).
Although acetonitrile is one of the most stable nitriles, it undergoes typical nitrile reactions and is used to produce many types of nitrogen-containing compounds. It can be trimerized to S-trimethyltriazine and has been telomerized with ethylene and copolymerized with alpha-epoxides.
Acetonitrile produces hydrogen cyanide when heated to decomposition or when reacted with acids or oxidizing agents.
USES OF CYANOMETHANE
Being a volatile highly polar solvent, acetonitrile finds its greatest use as an extracting fluid for fatty acids and animal and vegetable oils.
Acetonitrile has been widely used as an extractive distillation solvent in the petrochemical industry for separating olefin-diolefin mixtures and for C4-hydrocarbons.
Acetonitrile has been used as a solvent for polymer spinning and casting because of the combination of high solubility and desirable intermediate volatility. It is also used as a solvent for isolating components from crude products such as crude wool resin.
Acetonitrile is used as a common laboratory solvent for recrystallizing various chemicals and is widely used as a solvent in HPLC analysis. Acetonitrile is also used in biotechnology research as a solvent in the synthesis of DNA and peptide sequencing.
Acetonitrile can be used to remove tars, phenols and colouring matter from petroleum hydrocarbons that are not soluble in acetonitrile. Acetonitrile is also used as a starting material for the synthesis of many chemicals such as acetophenone, alpha-naphthyl acetic acid, thiamine and acetomidine.
Extraction of fatty acids and animal and vegetable oils. Extraction of unsaturated petroleum hydrocarbons
Solvent for polymer spinning and casting
Moulding of plastics
Removal of tars, phenols and colouring matter from petroleum
Purification of wool resin
Recrystallization of steroids
Starting material for synthesis of chemicals
Solvent in DNA synthesis and peptide sequencing
Medium for promoting reactions
Solvent in non-aqueous titrations
Non-aqueous solvent for inorganic salts
High-pressure liquid chromatographic analysis
Catalyst and component of transition-metal complex catalysts
Extraction and refining of copper
Stabilizer for chlorinated solvents
Health & Safety:
R-phrases: R11 Highly flammable. R20/21/22 Harmful by inhalation, in contact with skin and if swallowed. R36 Irritating to eyes.
S-phrases: S16 Keep away from sources of ignition – No smoking. S36/37 Wear suitable protective clothing and gloves.
For full details see MSDS for Cyanomethane