Chlorine dioxide

  • Chlorine oxide
  • Chlorine peroxide
  • Chlorine(IV) oxide
  • Chlorine dioxide, hydrate, frozen
Formula
ClO2
Structure
Description
Yellow to reddish-yellow gas at room temp. Unpleasant odor similar to chlorine and nitric acid.
Uses
Bleaching cellulose, flour, leather, oils, textiles, beeswax, purification of water, taste & odor control of water, cleaning and detanning leather, manufacture of chlorine salts, oxidizing agent, bactericide & antiseptic.

Registry Numbers and Inventories.
CAS
10049-04-4
EC (EINECS/ELINCS)
233-162-8
EC Index Number
006-089-01-X
EC Class
Toxic; Corrosive; Dangerous for the Environment
RTECS
FO3000000
RTECS class
Mutagen; Reproductive Effector; Primary Irritant
UN (DOT)
9191
Merck
12,2146
Beilstein/Gmelin
1265 (G)
EPA OPP
20503
Swiss Giftliste 1
G-1402
Canada DSL/NDSL
DSL
US TSCA
Listed
Austrailia AICS
Listed
New Zealand
Listed
Japan ENCS (MITI)
Listed
Korea ECL
Listed

Properties.
Formula
ClO2
Formula mass
67.45
Melting point, °C
-59.5
Boiling point, °C
11
Vapor pressure, mmHg
88 (-29.6 C)
Vapor density (air=1)
2.33
Density
1.5 g/cm3
Solubility in water
3 g/L
Viscosity
0.000132 cp (294 C)

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
Gas explodes via heat, electric spark, light, or contact with organics. Mixing with carbon dioxide and polyatomic gases increases safety. Can be handled safely when diluted with air to 8-12% chlorine dioxide.
Protection
Wear appropriate protective gloves, clothing and goggles.
Respirators
Wear positive pressure self-contained breathing apparatus (SCBA).
Small spills/leaks
Keep away from combustibles material. Avoid contact unless wearing appropriate protective clothing. Flush area with flooding quantities of water. See assistance of a specialist.
Stability
Unstable in light; stable in dark if pure, but chlorides catalyze its decomposition even in dark. Solutions in pure water can be maintained for months in closed containers.
Incompatibilities
Avoide contact with carbon monoxide, hydrogen, mercury, non-metals, phosphorus pentachloride, potassium hydroxide and organic materials,. Reacts with water or steam to produce toxic and corrosive fumes of hydrochloric acid.
Decomposition
Hydrogen chloride.

Fire.
Lower exp. limit, %
>10
Fire fighting
Small Fires: Use water. Do not use dry chemicals or foams. carbon dioxide or Halon may provide limited control. Large Fires: Flood fire area with water from a distance.
Fire potential
Dangerous; powerful oxidizer. Concn above 10% can ignite @ 130 C. Oxidizable organic dusts can lower decomposition temperature.
Hazards
May ignite combustibles (wood, paper, oil, clothing, etc.). Some will react explosively with hydrocarbons (fuels).
Combustion products
Fire may produce irritating and/or toxic gases.
 
Special
O

Health.
Exposure limit(s)
OSHA PEL: TWA 0.1 ppm (0.3 mg/m3) NIOSH REL: TWA 0.1 ppm (0.3 mg/m3) ST 0.3 ppm (0.9 mg/m3) NIOSH IDLH: 5 ppm
Poison_Class
1
Exposure effects
Rapid heart rate and rapid breathing are common. Severe exposure may cause cardiovascular collapse and respiratory arrest. Headache may develop. Agitation and anxiety may develop in patients with significant respiratory compromise. Chlorine (as hypochlorite) has been teratogenic in experimental animals. Mutations were detected using sperm morphology in mouse studies.
   Ingestion
Vomiting may occur following initial exposure.
   Inhalation
Feeling of burning and suffocation, coughing, choking, laryngeal edema hypoxia and, in high concentrations, syncope and almost immediate death may follow. Pulmonary edema is common after severe exposure.
   Skin
Dermal exposure may cause erythema, pain, irritation, and cutaneous burns.
   Eyes
Green hair, dental enamel erosion, inflammation of the eye, and nasal and throat irritation may occur. Anosmia is reported.

First aid
 
   Ingestion
Seek medical assistance.
   Inhalation
Move patient to fresh air. Monitor for respiratory distress. If cough or difficulty breathing develops, evaluate for respiratory tract irritation, bronchitis, or pneumonitis. Administer oxygen and assist ventilation as required. Treat bronchospasm with beta2 agonist and corticosteroid aerosols.
   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
9191
Response guide
Hazard class
5.1
Packing Group
II
 
USCG CHRIS Code
CLO