VCM (Vinyl Chloride Monomer)
Description
Vinyl Chloride Monomer (VCM, Monochloroethylene) is a reactive gas with a faint odor and is extremely flammable. Under refrigeration, VCM is converted into liquid with a density of 0.91 gm/cc.
VCM is sparingly soluble in water and soluble in alcohol.
Properties
| Unit | Quantity / Description |
|---|
| Molecular weight | g/mol | 62.5 |
| B.P. at 1.0 atm | °C | -13.8 |
| Freezing point | °C | -158.8 |
Specifications
| Unit | Quantity / Description |
|---|
| Purity | % mol | 99.9 min |
| Color | | colorless |
| Appearance | | clear |
| Ethylene | ppm, mol | 2 max |
| Acetylene | ppm, mol | 2 max |
| Propylene | ppm, mol | 3 max |
| 1-3 Butadiene | ppm, mol | 10 max |
| Total dichloro compound | ppm, mol | 20 max |
| Water | ppm, wt | 100 max |
| Acidity as HCL | ppm, wt | 2 max |
| Iron | ppm, wt | 0.5 max |
| Non volatile residue | ppm, wt | 100 max |
| Hydroquinone | ppm, wt | 2 min 5 max |
Hazards and safety
VCM is extremely flammable and known as a human carcinogen. Large fires triggered by VCM are difficult to extinguish. It has dangerous toxic effects when absorbed by the skin or inhaled. It also causes severe irritation of the eyes.
| Unit | Quantity |
|---|
| Threshold limit value | ppm | 1 |
| Flash point | °C | -78 |
| Explosive limits | vol % in air | 3.6-33 |
Applications
About 98% of VCM production is polymerized to produce Polyvinyl Chloride (PVC), a commonly used plastic, particularly in the piping and construction industries.
Storage and handling
VCM is stored as a liquid at -14°C to -22°C in large spherical steel tanks with 56 ppm of hydroquinonme stabilizer. Avoid contact with copper, any ignition source or heat. Keep away from oxidizing agents, caustic soda and reactive metals. Wear goggles, selfcontained breathing apparatus and rubber over clothing.
Packaging
VCM stabilized liquid is shipped in spherical refrigerated steel tanks. Between loads, the vessel tank must be carefully dried, then purged with nitrogen. VCM in a gaseous form must be controlled carefully under refrigeration.
UN or ID No. 1086.
Operating companies
Arabian Petrochemical Company (PETROKEMYA).
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