Hafnium

  • Hafnium powder, dry
Formula
Hf
Structure
Description
Hafnium powder, dry, is a grayish metallic colored powder.
Uses
Used for reactor control rods, in gas-filled & incandescent lamps, scavenger for oxygen & nitrogen.

Registry Numbers and Inventories.
CAS
7440-58-6
EC (EINECS/ELINCS)
231-166-4
RTECS
MG4600000
RTECS class
Other
UN (DOT)
2545
Merck
12,4618
Beilstein/Gmelin
16293 (G)
Swiss Giftliste 1
G-4689
Canada DSL/NDSL
DSL
US TSCA
Listed
Korea ECL
Listed

Properties.
Formula
Hf
Formula mass
178.49
Melting point, °C
2224
Boiling point, °C
5400
Density
13.31 g/cm3 (20 C)
Solubility in water
Insoluble
Viscosity
0.052 P (2231 C)
Thermal expansion
6.01E-5/K

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
Wear appropriate protective gloves, clothing and goggles.
Respirators
Wear positive pressure self-contained breathing apparatus (SCBA).
Small spills/leaks
Keep sparks, flames, and other sources of ignition away. Keep material out of water sources and sewers. Land spill: Dig a pit, pond, lagoon, holding area to contain liquid or solid material. Apply approriate foam to diminish vapor and fire hazard. Water spill: Use natural barriers or oil spill control booms to limit spill travel.
Stability
May explosively decompose on shock, friction, or concussion. May explode on heating. The substance may spontaneously ignite on contact with air and at higher temperatures.
Incompatibilities
Reacts exothermically with compounds having active hydrogen atoms (such as acids and water) to form flammable hydrogen gas and caustic products May react with azo/diazo compounds to form explosive products Can react explosively with oxidizing materials.

Fire.
Fire fighting
Use suitable dry powder. Use dry chemical or carbon dioxide. Use water only if flooding quantities are available.
Fire potential
Flammable/combustible material.
Hazards
May react violently or explosively on contact with water. Some are transported in flammable liquids. May be ignited by friction, heat, sparks or flames. Some of these materials will burn with intense heat. Dusts or fumes may form explosive mixtures in air. Containers may explode when heated. May re-ignite after fire is extinguished.
Combustion products
Toxic gases and vapors (such as hydrogen chloride and carbon monoxide) may be released in a fire involving hafnium.

Health.
Exposure limit(s)
OSHA PEL: TWA 0.5 mg/m3 *Note: The PEL also applies to other Hf cmpds (as Hf). NIOSH REL: TWA 0.5 mg/m3 *Note: The REL also applies to other Hf cmpds (as Hf). NIOSH IDLH: 50 mg/m3 (as Hf)
Poison_Class
-
Exposure effects
   Ingestion
See Inhalation.
   Inhalation
Substance or decomposition products may cause severe injury or death.
   Skin
Irritation of unabraded skin occurs with direct contact.
   Eyes
Eye irritation may be seen.

First aid
 
   Ingestion
Seek medical assistance.
   Inhalation
Move victim to fresh air. Apply artificial respiration if victim is not breathing. Administer oxygen if breathing is difficult.
   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
2545
Response guide
Hazard class
4.2
Packing Group
I; II; III
 
Std. Transport #
4916712