Benzoquinone

  • 2,5-Cyclohexadiene-1,4-dione
  • p-Quinone
  • Quinone
  • 1,4-Benzoquinone
Formula 4-(O=)C6H4=O
Structure
Description Yellow solid, acrid chlorine-like odor.
Uses Tanning hides, making gelatin insol, strengthening animal fibers.

Registry Numbers and Inventories.
CAS 106-51-4
EC (EINECS/ELINCS) 203-405-2
EC Index Number 606-013-00-3
EC Class Toxic; Irritant; Dangerous for the Environment
EC Risk Phrase R 23/25 36/37/38 50
EC Safety Phrase S 26 28 45 61
RTECS DK2625000
RTECS class Agricultural Chemical and Pesticide; Tumorigen; Mutagen
UN (DOT) 2587
Merck 12,8259
Beilstein/Gmelin 773967
Beilstein Reference 4-07-00-02065
RCRA U197
EPA OPP 59805
Swiss Giftliste 1 G-1228
Canada DSL/NDSL DSL
US TSCA Listed
Austrailia AICS Listed
New Zealand Listed
Japan ENCS (MITI) Listed
Korea ECL Listed

Odor Threshold Odor threshold 0.4000 mg/m3
Properties.
Formula C6H4O2
Formula mass 108.10
Melting point, °C 112 - 114
Boiling point, °C 174
Vapor pressure, mmHg 1.2 (25 C)
Vapor density (air=1) 3.7
Saturation Concentration 118 ppm (0.01%) at 20 C (calculated)
Density 1.318 g/cm3 (20 C)
Solubility in water 10 g/L
Viscosity 3.2585x10-2 n/m @ melting point
Surface tension 31.81 g/s2 (124 C)
Partition coefficient, pKow 0.20
Heat of vaporization 41.0 kJ/mol
Heat of combustion -2757 kJ/mol

Hazards and Protection.
Storage Store in a tightly closed container. Store in a cool, dry, well-ventilated area away from incompatible substances.
Handling Wash thoroughly after handling. Remove contaminated clothing and wash before reuse. Use only in a well ventilated area. Minimize dust generation and accumulation. May form flammable dust-air mixtures. Do not get in eyes, on skin, or on clothing. Keep container tightly closed. Do not ingest or inhale.
Protection Eyes: Wear appropriate protective eyeglasses or chemical safety goggles as described by OSHA's eye and face protection regulations in 29 CFR 1910.133 or European Standard EN166. Skin: Wear appropriate protective gloves to prevent skin exposure. Clothing: Wear appropriate protective clothing to prevent skin exposure.
Respirators Follow the OSHA respirator regulations found in 29CFR 1910.134 or European Standard EN 149. Always use a NIOSH or European Standard EN 149 approved respirator when necessary.
Small spills/leaks Sweep up, then place into a suitable container for disposal. Avoid generating dusty conditions. Remove all sources of ignition. Provide ventilation.
Disposal code 9
Stability Stable under normal temperatures and pressures.
Incompatibilities Oxidizing agents. Attacks some forms of coatings, plastics and rubber.
Decomposition Carbon monoxide, carbon dioxide.

Fire.
Flash Point,°C 59
Autoignition, °C 560
Fire fighting Wear a self-contained breathing apparatus in pressure-demand, MSHA/NIOSH (approved or equivalent), and full protective gear. Dusts at sufficient concentrations can form explosive mixtures with air. To extinguish fire, use water, dry chemical, chemical foam, or alcohol-resistant foam.
Fire potential Combustible.
Hazards When heated, vapors may form explosive mixtures with air: indoors, outdoors, and sewers explosion hazards.
Combustion products Contain irritating and toxic fumes, including carbon dioxide and carbon monoxide.
NFPA Health 3
  Flammability 2  
  Reactivity 0  

Health.
Exposure limit(s) TLV: 0.1 ppm; 0.44 mg/m3 (as TWA) (ACGIH 1997). OSHA PEL: TWA 0.4 mg/m3 (0.1 ppm) NIOSH REL: TWA 0.4 mg/m3 (0.1 ppm) NIOSH IDLH: 100 mg/m3
Poison_Class 3
Exposure effects Prolonged or repeated exposure may cause permanent eye damage.
   Ingestion Harmful if swallowed. May cause irritation of the digestive tract. Ingestion may cause convulsion, respiratory difficulties and decreased blood pressure.
   Inhalation Causes respiratory tract irritation. May cause adverse central nervous system effects including headache, convulsions, and possible death. May produce asphyxia due to pulmonary damage and effects on the hemoglobin. May produce clonic convulsions, respiratory difficulties, decreased blood pressure and death due to medullary centers.
   Skin Causes skin irritation. Depigmentation and skin lesions may occur. May cause discoloration, erythema, swelling, and the formation of papules and vesicles. Prolonged contact may lead to necrosis.
   Eyes Causes severe eye burns. Contact may cause discoloration, redness, swelling, and formation of eye lesions. May cause corneal edema, ulceration, and scarring. Prolonged exposure to vapor can lead to gradual deposition of pigment in the cornea and conjunctiva which may result in severe visual disturbances. Causes small opacities of the cornea and structural corneal changes that result in in loss of visual activity. Contact may cause discoloration, redness, swelling and formation of eye lesions.

First aid
 
   Ingestion If victim is conscious and alert, give 2-4 cupfuls of milk or water. Never give anything by mouth to an unconscious person. Get medical aid immediately.
   Inhalation Remove from exposure to fresh air immediately. If not breathing, give artificial respiration. If breathing is difficult, give oxygen. Get medical aid.
   Skin Get medical aid. Flush skin with plenty of soap and water for at least 15 minutes while removing contaminated clothing and shoes. Wash clothing before reuse.
   Eyes Flush eyes with plenty of water for at least 15 minutes, occasionally lifting the upper and lower eyelids. Get medical aid immediately. Do NOT allow victim to rub or keep eyes closed.

Transport.
UN number 2587
Response guide 153
Hazard class 6.1
Packing Group II  
USCG CHRIS Code BZQ  
HS Code 2914 69 90  
Std. Transport # 4921544