Catechol

  • Pyrocatechol
  • 1,2-Benzenediol
  • 1,2-Dihydroxybenzene
Formula
C6H4(OH)2
Structure
Description
Colorless crystalline solid with a faint odor, sublimes readily.
Uses
As an antioxidant in the rubber, chemical, photographic, dye, fat, & oil industries, in cosmetics & some pharmaceuticals.

Registry Numbers and Inventories.
CAS
120-80-9
EC (EINECS/ELINCS)
204-427-5
EC Index Number
604-016-00-4
EC Class
Harmful; Irritant
R 21/22 36/38
S 22 26 37
RTECS
UX1050000
RTECS class
Agricultural Chemical and Pesticide; Tumorigen; Mutagen; Reproductive Effector
UN (DOT)
2811
Merck
12,8183
Beilstein/Gmelin
471401
Beilstein Reference
4-06-00-05557
Swiss Giftliste 1
G-1289
Canada DSL/NDSL
DSL
US TSCA
Listed
Austrailia AICS
Listed
New Zealand
Listed
Japan ENCS (MITI)
Listed
Korea ECL
Listed

Properties.
Formula
C6H6O2
Formula mass
110.11
Melting point, °C
103 - 105
Boiling point, °C
245
Vapor pressure, mmHg
0.018 (25 C)
Vapor density (air=1)
3.79
Saturation Concentration
1316 ppm (0.13%) at 75 C (calculated)
Density
1.0548 g/cm3 (20 C)
Solubility in water
430 g/L
Viscosity
2.17 cp (121 C)
Refractive index
1.515 (20 C)
pKa/pKb
9.50 (pKa)
Partition coefficient, pKow
0.88
Heat of fusion
15.0 kJ/mol
Heat of vaporization
50.2 kJ/mol
Heat of combustion
-2865 kJ/mol

Hazards and Protection.
Storage
Keep container closed when not in use. Material can ignite if dry. Do not allow material to completely dry. Keep from contact with oxidizing materials. Corrosives area. Store in a cool, dry 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. Do not breathe dust, vapor, mist, or gas. Do not get in eyes, on skin, or on clothing. Keep container tightly closed. Discard contaminated shoes.
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
A respiratory protection program that meets OSHA's 29 CFR 1910.134 and ANSI Z88.2 requirements or European Standard EN 149 must be followed whenever workplace conditions warrant a respirator's use.
Small spills/leaks
Vacuum or sweep up material and place into a suitable disposal container. Clean up spills immediately, using the appropriate protective equipment. Avoid generating dusty conditions. Remove all sources of ignition. Provide ventilation.
Stability
Stable under normal shipping and handling conditions. Substance undergoes color change upon exposure to light and air.
Incompatibilities
Strong oxidizing agents, strong reducing agents, strong acids, strong bases.
Decomposition
Carbon monoxide, irritating and toxic fumes and gases, carbon dioxide.

Fire.
Flash Point,°C
127
Autoignition, °C
567
Upper exp. limit, %
9.8
Lower exp. limit, %
1.6
Fire fighting
Wear a self-contained breathing apparatus in pressure-demand, MSHA/NIOSH (approved or equivalent), and full protective gear. During a fire, irritating and highly toxic gases may be generated by thermal decomposition or combustion. Use water spray to keep fire-exposed containers cool. Contact with metals may evolve flammable hydrogen gas. Containers may explode when heated. Non-combustible, substance itself does not burn but may decompose upon heating to produce irritating, corrosive and/or toxic fumes. Extinguishing media: Do NOT get water inside containers. For small fires, use dry chemical, carbon dioxide, or water spray. For large fires, use dry chemical, carbon dioxide, alcohol-resistant foam, or water spray. Cool containers with flooding quantities of water until well after fire is out.
Fire potential
This material is combustible.
Hazards
POISONOUS GASES MAY BE PRODUCED WHEN HEATED. May form toxic fumes at high temperatures.
Combustion products
Fire may produce irritating, corrosive and/or toxic gases.
Health
3
 
Flammability
1
 
 
Reactivity
0
 

Health.
Exposure limit(s)
5 ppm TLV
Carcinogin
G-A3, I-2B, CP65
Poison_Class
2
Exposure effects
Chronic inhalation and ingestion may cause effects similar to those of acute inhalation and ingestion. May cause methemoglobinemia, which is characterized by chocolate-brown colored blood, headache, weakness, dizziness, breath shortness, cyanosis, rapid heart rate, unconsciousness and possible death. Effects may be delayed.
   Ingestion
Harmful if swallowed. May cause severe and permanent damage to the digestive tract. Causes gastrointestinal irritation with nausea, vomiting and diarrhea. May cause perforation of the digestive tract. May cause methemoglobinemia, cyanosis, convulsions, and death. May cause central nervous system depression. May cause systemic effects. May cause a prolonged rise in blood pressure which may lead to degenerative changes in the
   Inhalation
May cause severe irritation of the respiratory tract with sore throat, coughing, shortness of breath and delayed lung edema. Causes chemical burns to the respiratory tract. May cause effects similar to those described for ingestion. Aspiration may lead to pulmonary edema. May cause systemic effects.
   Skin
Harmful if absorbed through the skin. Causes skin burns. Prolonged and/or repeated contact may cause irritation and/or dermatitis. May cause skin sensitization, an allergic reaction, which becomes evident upon re-exposure to this material. If absorbed, causes symptoms similar to those of ingestion. May cause skin rash (in milder cases), and cold and clammy skin with cyanosis or pale color.
   Eyes
Causes eye burns. May cause chemical conjunctivitis and corneal damage.

First aid
 
   Ingestion
Do NOT induce vomiting. 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
Get medical aid immediately. Remove from exposure to fresh air immediately. If breathing is difficult, give oxygen. DO NOT use mouth-to-mouth respiration. If breathing has ceased apply artificial respiration using oxygen and a suitable mechanical device such as a bag and a mask.
   Skin
Get medical aid. Immediately flush skin with plenty of soap and water for at least 15 minutes while removing contaminated clothing and shoes. Wash clothing before reuse. Destroy contaminated shoes.
   Eyes
Get medical aid immediately. Do NOT allow victim to rub or keep eyes closed. Extensive irrigation is required (at least 30 minutes).

Transport.
UN number
2811
Response guide
Hazard class
6.1
Packing Group
I; II; III
 
USCG CHRIS Code
CTC
 
HS Code
2907 29 00