General Description
A colorless or slightly yellow fuming liquid with a pungent and irritating odor resembling that of hydrochloric acid. Causes severe burns to skin, eyes and mucous membranes. Very toxic by inhalation, ingestion and skin absorption. Reacts with water to evolve hydrochloric acid, an irritating and corrosive gas apparent as white fumes. Used during electrodeposition of metal on rubber and for making pesticides, surfactants, gasoline additives, plasticizers, dyestuffs, textile finishing agents, germicides, medicinal products, and other chemicals.
Reactivity Profile
PHOSPHORUS TRICHLORIDE is a strong reducing agent that may ignite combustible organic materials upon contact. May generate flammable and potentially explosive gaseous hydrogen upon contact with many common metals (except nickel and lead). Reactions with water are violent and produce heat and flashes of fire [AAR, 1999]. Gives intensely exothermic reactions with iodine monochloride [Mellor 2, Supp. 1:502. 1956]. Several laboratory explosions have been reported arising from mixtures with acetic acid, along with other acids, sulfuric acid and derivatives, carboxylic acids, etc. These have been ascribed to poor heat control allowing the formation of phosphine [J. Am. Chem. Soc. 60:488. 1938]. Ignites when mixed with hydroxylamine [Mellor 8:290. 1946-47]. Causes an explosion on contact with nitric acid [Comp. Rend. 28:86]. PHOSPHORUS TRICHLORIDE is incompatible with many common oxidants such as: sodium peroxide, fluorine, chromyl chloride, iodine chloride, to name a few. Isopropanol can react with PCl3, forming toxic HCl gas. (Logsdon, John E., Richard A. Loke., "Isopropyl Alcohol." Kirk-Othmer Encyclopedia of Chemical Technology. John Wiley & Sons, Inc. 1996.)
Health Hazard
This material is highly toxic; it may cause death or permanent injury. Contact is highly irritating to the skin, eyes, and mucous membranes, and the material is an irritant through oral and inhalation exposure.
Potential Exposure
Phosphorus trichloride is used as an intermediate and as a chlorinating agent and catalyst; in the manufacture of agricultural chemicals; pharmaceuticals, chlorinated compounds; dyes, gasoline additives; acetyl cellulose; phosphorus oxychloride; plasticizers, saccharin, and surfactants.
Fire Hazard
This material will react violently with water, producing heat and toxic and corrosive fumes. When heated to decomposition, PHOSPHORUS TRICHLORIDE emits highly toxic fumes of chlorides and phosphorus oxides. PHOSPHORUS TRICHLORIDE may ignite other combustible materials. Reacts violently with water. Reacts explosively with acetic acid, aluminum, chromyl chloride, diallylphosphite and allyl alcohol, dimethyl sulfoxide, fluorine, hydroxylamine, iodine monochloride, lead dioxide, nitric acid, nitrous acid, organic matter, potassium, and sodium. Avoid contact with water, steam, or acids. Hazardous polymerization may not occur.
First aid
If this chemical gets into the eyes, remove any contact lenses at once and irrigate immediately for at least 30 minutes, occasionally lifting upper and lower lids. Seek medical attention immediately. If this chemical contacts the skin, remove contaminated clothing and wash immediately with soap and water. Seek medical attention immediately. If this chemical has been inhaled, remove from exposure, begin rescue breathing (using universal precautions, including resuscitation mask) if breathing has stopped and CPR if heart action has stopped. Transfer promptly to a medical facility. When this chemical has been swallowed, get medical attention. If victim is conscious, administer water, or milk. Do not induce vomiting. Medical observation is recommended for 2448 hours after breathing overexposure, as pulmonary edema may be delayed. As first aid for pulmonary edema, a doctor or authorized paramedic may consider administering a drug or other inhalation therapy
Shipping
UN1809 Phosphorous trichloride, Hazard class: 6.1; Labels: 6.1-Poisonous materials, 8-Corrosive material, Inhalation Zone B.
Incompatibilities
Phosphorus trichloride is a strong reducing Violent reaction with water, producing heat and hydrochloric and phosphorous acids. Violent reaction with hydrides, alcohols, phenols and bases; water, when in contact with combustible organics; chemically active metals: sodium, potassium, aluminum; strong sulfuric or nitric acid. Attacks most metals except nickel and lead; may generate flammable hydrogen gas on contact with metals. Attacks plastics, rubber, and coatings.
Description
Phosphorus trichloride, PCl3, is a clear, colorless, fuming, corrosive liquid. It decomposes rapidly in moist air and has a boiling point of about 168°F (75°C). PCl3 is corrosive to skin and tissue and reacts with water to form hydrochloric acid. The TLV is 0.2 ppm, and the IDLH is 50 ppm in air. The four-digit UN identification number is 1809. The NFPA 704 designation is health 4, flammability 0, and reactivity 2. The white section at the bottom of the diamond contains a W with a slash through it, indicating water reactivity. The primary uses are in the manufacture of organophosphate pesticides, gasoline additives, and dyestuffs; as a chlorinating agent; as a catalyst; and in textile finishing. Corrosives in contact with a poison may produce poison gases as the poison decomposes. In responding to an incident involving corrosives, the toxicity of the vapors could be much more of a concern for personnel than the corrosivity. When acids come in contact with cyanide, hydrogen cyanide gas, which is highly toxic, with a TLV of 10 ppm in air, is produced.
Waste Disposal
Decompose with water, forming phosphoric and hydrochloric acids. The acids may then be neutralized and diluted slowly to solution of soda ash and slaked lime with stirring, then flush to sewer with large volumes of water.
Physical properties
Colorless fuming liquid; pungent odor; refractive index 1.516 at 14°C; density 1.574g/mL at 21°C; boils at 76°C; freezes at -112°C; decomposes in water; soluble in benzene, carbon disulfide, ether and chloroform and other halogenated organic solvents.
Definition
ChEBI: Phosphorus trichloride is a phosphorus halide with formula Cl3P.
Production Methods
Phosphorus trichloride (PCl3) is made by reacting yellow
phosphorus with chlorine and is used in chemical
manufacturing. It hydrolyzes to phosphoric acid and hydrochloric
acid.
Hazard
Phosphorus trichloride is highly corrosive. Its vapors are an irritant to mucous membranes. Chronic exposure to its vapors can cause bronchitis. It reacts violently with water and explodes in contact with acetic and nitric acids, and several other substances (Patnaik. P. 1999. A Comprehensive Guide to the Hazardous Properties of Chemical Substances, 2nd. Ed. New York: John Wiley & Sons).
Flammability and Explosibility
Nonflammable
Purification Methods
Heat it under reflux to expel dissolved HCl, then distil it. It has been further purified by vacuum fractionation several times through a -45o trap into a receiver at -78o. [Forbes Inorg Synth II 145 1946.] HARMFUL VAPOURS.
