Purify ethylene by passage through a series of towers containing molecular sieves or anhydrous CaSO4 or a cuprous ammonia solution, then conc H2SO4, followed by KOH pellets. Alternatively, it has been condensed in liquid nitrogen, with melting, freezing and pumping to remove air before passage through an activated charcoal trap, followed by a further condensation in liquid air. A sputtered sodium trap was used to remove oxygen. [Beilstein 1 IV 677.]
Moderate concentration in air causes drowsiness, dizziness, and unconsciousness. Overexposure causes headache, drowsiness, muscular weakness.
Oxyethylene welding and cutting metals; manufacture of alcohol, mustard gas, and many other organics. manufacture of ethylene oxide (for plastics), "Polythene", polystyrene and other plastics. Plant growth regulator; used commercially to accelerate the ripening of various fruits.
Air & Water Reactions
A colorless gas with a sweet odor and taste. ETHYLENE is lighter than air. ETHYLENE is easily ignited and a flame can easily flash back to the source of the leak. Under prolonged exposure to fire or heat the containers may rupture violently and rocket. Can cause explosion.
Peroxidizable monomer may initiate exothermic polymerization of the bulk material [Bretherick 1979. p. 160]. ETHYLENE in the presence of aluminum chloride may undergo a violent reaction [J. Inst. Pet. 33:254. 1947]. Ozone and ETHYLENE react explosively [Berichte 38:3837]. ETHYLENE can polymerize at low pressure if catalyzed by titanium halides. (Sundaram, K. M, M. M. Shreehan, E. F. Olszewski. thylene. Kirk-Othmer Encyclopedia of Chemical Technology. John Wiley & Sons, Inc. 2001.)