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

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
Odor Threshold Odor threshold 4.50 mg/m3
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.
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
Hazard class
2.3
PRTC
T
USCG CHRIS Code
BFD
 
Std. Transport #
4920522