1,2,3-Trimethylbenzene

  • Hemimellitene
Formula C9H12
Structure
Description Clear, colorless liquid with a distinctive, aromatic odor.

Registry Numbers and Inventories.
CAS 526-73-8
EC (EINECS/ELINCS) 208-394-8
RTECS DC3300000
RTECS class Mutagen
UN (DOT) 1993
Beilstein/Gmelin 1903410
Beilstein Reference 4-05-00-01007
Canada DSL/NDSL DSL
US TSCA Listed
Austrailia AICS Listed
New Zealand Listed
Japan ENCS (MITI) Listed
Korea ECL Listed

Properties.
Formula C9H12
Formula mass 120.21
Melting point, °C -25
Boiling point, °C 175
Vapor pressure, mmHg 1
Vapor density (air=1) 4.15
Critical temperature 392
Critical pressure 33.98
Density 0.9101 g/cm3 (0 C)
Solubility in water Slightly soluble
Surface tension 31.27 g/s2 (20 C)
Refractive index 1.5093 (19.5 C)

Hazards and Protection.
Storage Keep away from heat, sparks, and flame. Keep away from sources of ignition. Keep container closed when not in use. Flammables-area.
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 protective gloves, clothing and goggles.
Respirators Wear positive pressure self-contained breathing apparatus (SCBA).
Small spills/leaks Make no contact with the spilled material. ELIMINATE all ignition sources and ground all equipment. Stop leak if you can do it without risk. A vapor suppressing foam may be used to reduce vapors. Absorb or cover with dry earth, sand or other non-combustible material and transfer to containers. Use clean non-sparking tools to collect absorbed material.
Stability No data.
Incompatibilities Keep away from nitric acid and oxidizers.
Decomposition Oxides of carbon.

Fire.
Flash Point,°C 51
Autoignition, °C 470
Upper exp. limit, % 5.2
Lower exp. limit, % 0.9
Fire fighting Use of water spray when fighting fire may be inefficient. Small Fires: Dry chemical, carbon dioxide, water spray or alcohol-resistant foam. Large Fires: Water spray, fog or alcohol-resistant foam. Use water spray or fog; do not use straight streams.
Fire potential HIGHLY FLAMMABLE: Will be easily ignited by heat, sparks or flames.
Hazards Vapors may form explosive mixtures with air. Vapors may travel to source of ignition and flash back. Most vapors are heavier than air. They will spread along ground and collect in low or confined areas (sewers, basements, tanks). Vapor explosion hazard indoors, outdoors or in sewers.
Combustion products Fire may produce irritating, corrosive and/or toxic gases.
NFPA Health 0
  Flammability 2  
  Reactivity 0  

Health.
Exposure limit(s) NIOSH REL: TWA 25 ppm (125 mg/m3)
Exposure effects The toxological properties of this substance have not been fully investigated.
   Ingestion May cause irritation.
   Inhalation Vapors may cause dizziness or suffocation. May cause irritation or burns.
   Skin May cause irritation or burns.
   Eyes See Skin.

First aid
 
   Ingestion Seek medical assistance.
   Inhalation Move victim to fresh air. Apply artificial respiration if victim is not breathing. Administer oxygen if breathing is difficult.
   Skin Remove and isolate contaminated clothing and shoes. Wash skin with soap and water. Flush with running water for at least 20 minutes
   Eyes Flush with running water for at least 20 minutes.

Transport.
UN number 1993
Response guide 128
Hazard class 3
Packing Group I; II; III  
USCG CHRIS Code TMD  
USCG Compatatibility Group 32 Aromatic hydrocarbons
IMO Chemical Code 17
IMO Pollution Category A
IMO Hazard code P