SELENIUM HEXAFLUORIDE Property

Melting point:

-39°C

Boiling point:

-34,5°C

Density 

1.66

solubility 

insoluble in H2O

form 

colorless gas

color 

colorless

Water Solubility 

insoluble H2O [MER06]

EPA Substance Registry System

Selenium hexafluoride (7783-79-1)

Safety

Hazard Codes 

T

Risk Statements 

23/25-33-34

Safety Statements 

20/21-28-45

RIDADR 

2194

OEB

E

OEL

TWA: 0.05 ppm

Hazard Note 

Highly Toxic

HazardClass 

2.3

Hazardous Substances Data

7783-79-1(Hazardous Substances Data)

IDLA

2 ppm

Hazard and Precautionary Statements (GHS)

Symbol(GHS)

Signal word

Danger

Hazard statements

H280Contains gas under pressure; may explode if heated

H314Causes severe skin burns and eye damage

H330Fatal if inhaled

Precautionary statements

P260Do not breathe dust/fume/gas/mist/vapours/spray.

P264Wash hands thoroughly after handling.

P264Wash skin thouroughly after handling.

P271Use only outdoors or in a well-ventilated area.

P280Wear protective gloves/protective clothing/eye protection/face protection.

P284Wear respiratory protection.

P301+P330+P331IF SWALLOWED: Rinse mouth. Do NOT induce vomiting.

P303+P361+P353IF ON SKIN (or hair): Remove/Take off Immediately all contaminated clothing. Rinse SKIN with water/shower.

P304+P340IF INHALED: Remove victim to fresh air and Keep at rest in a position comfortable for breathing.

P305+P351+P338IF IN EYES: Rinse cautiously with water for several minutes. Remove contact lenses, if present and easy to do. Continuerinsing.

P310Immediately call a POISON CENTER or doctor/physician.

P320Specific treatment is urgent (see … on this label).

P321Specific treatment (see … on this label).

P363Wash contaminated clothing before reuse.

P403+P233Store in a well-ventilated place. Keep container tightly closed.

P405Store locked up.

P410+P403Protect from sunlight. Store in a well-ventilated place.

P501Dispose of contents/container to..…

SELENIUM HEXAFLUORIDE Chemical Properties,Usage,Production

Chemical Properties

Selenium hexafluoride is a nonflammable, colorless gas. Repulsive odor.

Physical properties

Colorless gas; refractive index 1.895; density 3.25 g/L at -28°C; liquefies at -34.5°C; freezes at -50.8°C; sublimes at -63.8°C; insoluble in water.

Uses

Selenium hexafluoride is used as a gaseous electric insulator (146). It may be prepared by passing gaseous fluorine over finely divided selenium in a copper vessel. Industrial selenium exposure is common for makers of arc light electrodes, electric rectifiers, and semiconductors.

Uses

Gaseous electric insulator.

Preparation

Selenium hexafluoride is prepared by passing fluorine gas over finely divided selenium in a copper vessel:
Se + 3F₂ → SeF₆.

Definition

ChEBI: Selenium hexafluoride is a selenium coordination entity.

General Description

SELENIUM HEXAFLUORIDE is a colorless gas used as a electrical insulator. SELENIUM HEXAFLUORIDE is highly toxic by inhalation. When heated to high temperatures SELENIUM HEXAFLUORIDE may decompose to emit toxic fluoride and selenium fumes. Prolonged exposure of the container to fire or intense heat may cause SELENIUM HEXAFLUORIDE to violently rupture or rocket.

Air & Water Reactions

Insoluble in water.

Reactivity Profile

SELENIUM HEXAFLUORIDE is a colorless, poison gas, when heated to decomposition SELENIUM HEXAFLUORIDE emits very toxic fumes containing metallic selenium and selenium fluorides [Lewis, 3rd ed., 1993, p. 1131].

Health Hazard

TOXIC; may be fatal if inhaled, ingested or absorbed through skin. Vapors are extremely irritating and corrosive. Contact with gas or liquefied gas may cause burns, severe injury and/or frostbite. Fire will produce irritating, corrosive and/or toxic gases. Runoff from fire control may cause pollution.

Fire Hazard

Some may burn but none ignite readily. Vapors from liquefied gas are initially heavier than air and spread along ground. Some of these materials may react violently with water. Cylinders exposed to fire may vent and release toxic and/or corrosive gas through pressure relief devices. Containers may explode when heated. Ruptured cylinders may rocket.

Safety Profile

Poison by inhalation. When heated to decomposition it emits very toxic fumes of Fand Se. See also SELENIUM COMPOUNDS and FLUORIDES.

Potential Exposure

Selenium hexafluoride, a gas, is utilized as a gaseous electric insulator.

Shipping

Selenium hexafluoride, Hazard Class: 2.3; Labels: 2.3-Poisonous gas, 8-Corrosive material Inhalation, Hazard Zone A. Cylinders must be transported in a secure upright position, in a well-ventilated truck. Protect cylinder and labels from physical damage. The owner of the compressed gas cylinder is the only entity allowed by federal law (49CFR) to transport and refill them. It is a violation of transportation regulations to refill compressed gas cylinders without the express written permission of the owner.

Incompatibilities

Hydrolyzes very slowly in cold water. Decomposes on heating, producing hydrogen fluoride, fluoride, and selenium. Contact with metal or acid will produce toxic gaseous hydrogen selenide.

Waste Disposal

Return refillable compressed gas cylinders to supplier. If possible, convert selenium compounds to an insoluble form with SO2 before landfill or solidification.