Hexachlorocyclopentadiene

  • Perchlorocyclopentadiene
  • Hexachloro-1,3-cyclopentadiene
  • 1,2,3,4,5,5-Hexachloro-1,3-Cyclopentadiene
Formula
C5Cl6
Structure
Description
A pale yellow liquid with a pungent odor.
Uses
Intermediate for many insecticides, polyester resins, and flame retardants.

Registry Numbers and Inventories.
CAS
77-47-4
EC (EINECS/ELINCS)
201-029-3
EC Index Number
602-078-00-7
EC Class
Very toxic; Toxic; Harmful; Corrosive; Dangerous for the Environment
RTECS
GY1225000
RTECS class
Agricultural Chemical and Pesticide; Tumorigen; Reproductive Effector; Primary Irritant
UN (DOT)
2646
Beilstein/Gmelin
976722
Beilstein Reference
4-05-00-00381
RCRA
U130
EPA OPP
27502
Swiss Giftliste 1
G-2094
Canada DSL/NDSL
DSL
US TSCA
Listed
Austrailia AICS
Listed
New Zealand
Listed
Japan ENCS (MITI)
Listed
Korea ECL
Listed

Properties.
Formula
C5Cl6
Formula mass
272.75
Melting point, °C
12
Boiling point, °C
239
Vapor pressure, mmHg
0.052 (25 C)
Vapor density (air=1)
9.4
Odor Threshold Odor threshold 0.15 ppm
Critical temperature
475
Critical pressure
34.8
Density
1.7105 g/cm3 (20 C)
Solubility in water
2 mg/L (Reacts)
Surface tension
37.5 g/s2 (20 C)
Refractive index
1.5644 (20 C)
Partition coefficient, pKow
3.99
Heat of vaporization
46.0 kJ/mol

Hazards and Protection.
Storage
Tightly closed containers. Keep away from heat and water.
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 clothing to prevent any reasonable probability of skin contact. Wear eye protection to prevent any possibility of eye contact.
Respirators
Wear positive pressure self-contained breathing apparatus (SCBA).
Small spills/leaks
Keep material out of water sources and sewers. Build dikes to contain flow as necessary. Attempt to stop leak if without undue personnel hazard. Use water spray to knock-down vapors. Land spill: Dig a pit, pond, lagoon, holding area to contain liquid or solid material. Cover solids with a plastic sheet to prevent dissolving in rain or fire fighting water. Absorb bulk liquid with fly ash or cement powder. Water spill: Use natural deep water pockets, excavated lagoons, or sand bag barriers to trap material at bottom. Remove trapped material with suction hoses. Use mechanical dredges or lifts to remove immobilized masses of pollutants and precipitates.
Stability
No data.
Incompatibilities
Incompatible with strong oxidizing and reducing agents Incompatible with many amines, nitrides, azo/diazo compounds, alkali metals (sodium), and epoxides.

Fire.
Flash Point,°C
100
Fire fighting
Isolate hazard area and deny entry. Wear positive pressure breathing apparatus and special protective clothing. Fight fire from maximum distance. Dike fire control water for later disposal.Use dry chemical, carbon dioxide, water spray or foam for small fires. For large fires, use water spray, fog, or foam. Move hexachlorocyclopentadiene from fire area if this can be done without risk.
Fire potential
Nonflammable.
Hazards
Toxic hydrogen chloride, chlorine, and phosgene gases may form in fires. In presence of moisture, will corrode iron and other materials; flammable and explosive hydrogen gas may collect in enclosed space. Will corrode iron and other metals in the presence of moisture. Reacts slowly with water to form hydrochloric acid; however, the reaction is not hazardous.
Combustion products
Toxic hydrogen chloride, chlorine, and phosgene gases may form in fires.

Health.
Exposure limit(s)
NIOSH REL: TWA 0.01 ppm (0.1 mg/m3)
Poison_Class
2
Exposure effects
Headache is common. Degenerative CNS changes have been seen in experimental animals.
   Ingestion
Nausea may occur.
   Inhalation
The major target organ for c56 toxicity is the lung, regardless of the exposure route. Cough, dyspnea, and chest discomfort have been reported in exposed humans. Experimental animals have developed pulmonary edema, pulmonary hemorrhages, and necrotizing bronchitis and bronchiolitis.
   Skin
Skin irritation may occur from direct contact or vapor exposure. Direct skin contact with the liquid can cause dermal blistering and burns.
   Eyes
CONJUNCTIVITIS - Eye irritation is common. Irritation of the throat may be seen.

First aid
 
   Ingestion
The possible benefit of early removal of some ingested material by cautious gastric lavage must be weighed against potential complications of bleeding or perforation. Activated charcoal activated charcoal binds most toxic agents and can decrease their systemic absorption if administered soon after ingestion. Activated charcoal: administer charcoal as a slurry (240 ml water/30 g charcoal). Usual dose: 25 to 100 g in adults/adolescents.
   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. Treat dermal irritation or burns with standard topical therapy. Patients developing dermal hypersensitivity reactions may require treatment with systemic or topical corticosteroids or antihistamines.
   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
2646
Response guide
Hazard class
6.1
PRTC
T
Packing Group
I
 
USCG CHRIS Code
HCC
 
Std. Transport #
4921722