Boron trifluoride

  • Tribluoroborane
Formula BF3
Structure
Description Boron trifluoride is a colorless gas with a pungent odor.
Uses As a fumigant, in ionization chambers for detection of weak neutrons, to protect molten magnesium and its alloys from oxidation, as a flux for soldering magnesium.

Registry Numbers and Inventories.
CAS 7637-07-2
EC (EINECS/ELINCS) 231-569-5
EC Index Number 005-001-00-X
EC Class Reacts violently with water; Very toxic; Corrosive
RTECS ED2275000
RTECS class Other
UN (DOT) 1008
Merck 12,1379
Beilstein/Gmelin 1519 (G)
Swiss Giftliste 1 G-1284
Canada DSL/NDSL DSL
US TSCA Listed
Austrailia AICS Listed
New Zealand Listed
Japan ENCS (MITI) Listed
Korea ECL Listed

Odor Threshold Odor threshold 4.50 mg/m3
Properties.
Formula BF3
Formula mass 67.81
Melting point, °C -127
Boiling point, °C -100
Vapor pressure, mmHg 15589 (-35)
Vapor density (air=1) 2.4
Critical temperature -12.26
Critical pressure 49.2
Density 1.6 g/cm3 (20 C)
Solubility in water 3320 g/L
Viscosity 0.0171 m pa.s (25 C)
Surface tension 17.2 g/s2 (-100 C)
Dielectric constant 0.0011 (25 C)
Heat of fusion 4.2 kJ/mol
Heat of vaporization 17.0 kJ/mol

Hazards and Protection.
Storage Keep in a cool, dry, dark location in a tightly sealed container or cylinder. Keep away from incompatible materials, ignition sources and untrained individuals. Secure and label area. Protect containers/cylinders from physical damage.
Handling All chemicals should be considered hazardous. Avoid direct physical contact. Use appropriate, approved safety equipment. Untrained individuals should not handle this chemical or its container. Handling should occur in a chemical fume hood.
Protection Proper impervious protective clothing including gloves, aprons, suits, boots, goggles, and face shields as needed to prevent skin and eye contact.
Respirators Wear positive pressure self-contained breathing apparatus (SCBA).
Small spills/leaks Keep material out of water sources and sewers. Attempt to stop leak if without undue personnel hazard. Use water spray to knock-down vapors. Do not use water on material itself.
Stability Container of bf3 may explode in heat of fire. BF3-Diethyl etherate presents not only a container explosion hazard but also the vapors present an explosion hazard indoors, outdoors, or in sewers. Runoff to sewer also may create an explosion hazard.
Incompatibilities Incompatible with alkyl nitrates, calcium oxide Reaction with alkali metals or alkaline earth metals (except magnesium) will cause incandescence.
Decomposition When heated to decomp. Will produce. Fumes of hydrogen fluoride. Boron fluoride the toxic action of the halogenated borons is considerably influenced by their decomposition products (hydrofluoric acid-, fluoboric acid-, hydrochloric acid-).

Fire.
Flash Point,°C 4
Fire fighting Keep unnecessary people away; isolate hazard area and deny entry. Stay upwind; keep out of low areas. Ventilate closed spaces before entering them. Wear positive pressure breathing apparatus and full protective clothing. Evacuate area endangered by gas. Do not get water inside container. Move container from fire area if you can do it without risk. Stay away from ends of tanks. Cool containers that are exposed to flames with water from the side until well after fire is out. Isolate area until gas has dispersed.Extinguish with dry chemical, carbon dioxide, water spray, fog, or foam.
Fire potential Bf3 cannot catch fire.
Hazards When heated to decomposition or upon contact with water or steam, it will produce toxic and corrosive fumes of fluorine containing compounds. Decomposes upon heating or on contact with moist air, forming toxic and corrosive fumes of boric acid and hydrofluoric acid. Reacts with alkalis and fumes in moist air, producing particulates which reduce visibility. Reacts with alkali metals, alkaline earth metals (except magnesium), alkyl nitrates, and calcium oxide. It hydrolyzes in moist air to form boric acid, hydrofluoric acid, and fluoboric acid.
Combustion products When heated to decomp.
NFPA Health 4
  Flammability 0  
  Reactivity 1  

Health.
Exposure limit(s) TLV: 1 ppm; 2.8 mg/m3 (ceiling values) (ACGIH 1992-1993). PDK: 0.1 mg/m3 (USSR 1972). OSHA PEL: C 1 ppm (3 mg/m3) NIOSH REL: C 1 ppm (3 mg/m3) NIOSH IDLH: 25 ppm
Poison_Class 2
Exposure effects Acute exposure to boron trifluoride gas has resulted in rapid loss of consciousness.
   Inhalation Acute inhalations have resulted in hypoxemia.
   Skin Skin irritation is expected on contact. When soaked into a cotton ball and placed on the skin for 1 to 2 days, boron fluoride left a hf type burn.
   Eyes Teeth: Rats exposed to 15 to 100 ppm developed hypoplasia of the teeth and excessive fluoride deposition. Nose bleed and nasal dryness has been reported in humans.

First aid		  
   Ingestion WIth acute ingestions, severe gastritis or gastroenteritis with abdominal pain may be seen. Vomiting begins within an hour. Diarrhea with watery, tarry feces may follow with dehydration. Liver injury will occur.
   Inhalation Move victim to fresh air. Apply artificial respiration if victim is not breathing. Do not use mouth-to-mouth method if victim ingested or inhaled the substance; induce artificial respiration with the aid of a pocket mask equipped with a one-way valve or other proper respiratory medical device. Administer oxygen if breathing is difficult. Effects may be delayed.
   Skin Remove contaminated clothing and wash exposed area thoroughly with soap and water. A physician should examine the area if irritation or pain persists.
   Eyes Irrigate exposed eyes with copious amounts of tepid water for at least 15 minutes. If irritation, pain, swelling, lacrimation, or photophobia persist, the patient should be seen in a health care facility.

Transport.
UN number 1008
Response guide 125
Hazard class 2.3
PRTC T
USCG CHRIS Code BFD  
Std. Transport # 4920522