1,2,4-Trimethylbenzene

  • Pseudocumene
Formula
C9H12
Structure
Description
Colorless liquid, distinctive aromatic odor.
Uses
Sterilizing catgut manufacture of dyes, perfumes & resins.

Registry Numbers and Inventories.
CAS
95-63-6
EC (EINECS/ELINCS)
202-436-9
EC Index Number
601-043-00-3
EC Class
Flammable; Harmful; Irritant; Dangerous for the Environment
R 10 20 36/37/38 51/53
RTECS
DC3325000
RTECS class
Mutagen
UN (DOT)
1993
Merck
12,8100
Beilstein/Gmelin
1903005
Beilstein Reference
4-05-00-01010
Swiss Giftliste 1
G-2816
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
120.20
Melting point, °C
-44
Boiling point, °C
169
Vapor pressure, mmHg
2 (20 C)
Vapor density (air=1)
4.15
Saturation Concentration
1300 ppm at 13.6 C (calc.)
Critical temperature
376.13
Critical pressure
32.3
Density
0.881 g/cm3 (15 C)
Solubility in water
60 mg/L
Viscosity
2.011 cp (20 C)
Surface tension
29.71 g/s2 @ 20 C
Refractive index
1.5044 (20 C)
Partition coefficient, pKow
3.41
Heat of vaporization
39.2 kJ/mol
Heat of combustion
-5365 kJ/mol

Hazards and Protection.
Storage
Keep away from heat, sparks, and flame. Keep away from sources of ignition. Store in a tightly closed container. Store in a cool, dry, well-ventilated area away from incompatible substances. Flammables-area.
B3
Handling
Wash thoroughly after handling. Use only in a well ventilated area. Ground and bond containers when transferring material. Use spark-proof tools and explosion proof equipment. Avoid breathing dust, vapor, mist, or gas. Avoid contact with eyes, skin, and clothing. Empty containers retain product residue, (liquid and/or vapor), and can be dangerous. Take precautionary measures against static discharges. Avoid contact with heat, sparks and flame. Avoid ingestion and inhalation. Do not pressurize, cut, weld, braze, solder, drill, grind, or expose empty containers to heat, sparks or open flames.
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
Absorb spill with inert material, (e.g., dry sand or earth), then place into a chemical waste container. Clean up spills immediately, using the appropriate protective equipment. Remove all sources of ignition. Use a spark-proof tool. Provide ventilation. A vapor suppressing foam may be used to reduce vapors.
Disposal code
1
Stability
Stable under normal temperatures and pressures.
Incompatibilities
Strong oxidizing agents, nitric acid.
Decomposition
Carbon monoxide, irritating and toxic fumes and gases, carbon dioxide.

Fire.
Flash Point,°C
48
Autoignition, °C
485
Upper exp. limit, %
7
Lower exp. limit, %
0.8
Fire fighting
Wear a self-contained breathing apparatus in pressure-demand, MSHA/NIOSH (approved or equivalent), and full protective gear. Will burn if involved in a fire. Use water spray to keep fire-exposed containers cool. Water may be ineffective. Material is lighter than water and a fire may be spread by the use of water. Containers may explode in the heat of a fire. Extinguishing media: For small fires, use dry chemical, carbon dioxide, water spray or alcohol-resistant foam. For large fires, use water spray, fog, or alcohol-resistant foam. Use water spray to cool fire-exposed containers. Water may be ineffective. This material is lighter than water and insoluble in water. The fire could easily be spread by the use of water.
Fire potential
Moderate fire risk. In absence of precautions, flammable concentration of vapor may be present where liquids are used in solvent and thinner operations. Trimethyl benzene
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.
Health
1
 
Flammability
2
 
 
Reactivity
0
 

Health.
Exposure limit(s)
NIOSH REL: TWA 25 ppm (125 mg/m3)
Poison_Class
4
Exposure effects
Prolonged or repeated skin contact may cause dermatitis. Repeated inhalation may cause chronic bronchitis. May cause anemia and other blood cell abnormalities. Prolonged exposure may produce a narcotic effect. Prolonged or repeated exposure may cause nausea, dizziness, and headache. Laboratory experiments have resulted in mutagenic effects.
   Ingestion
May cause gastrointestinal irritation with nausea, vomiting and diarrhea. May cause central nervous system depression.
   Inhalation
May cause drowsiness, unconsciousness, and central nervous system depression. Vapors may cause dizziness or suffocation. Causes irritation of the mucous membrane and upper respiratory tract.
   Skin
Causes skin irritation. May be absorbed through the skin. Causes redness and pain.
   Eyes
Causes eye irritation. Causes redness and pain. May cause irritation of the conjunctiva.

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.
   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.

Transport.
UN number
1993
Response guide
Hazard class
3
Packing Group
I; II; III
 
USCG CHRIS Code
TME
 
32 Aromatic hydrocarbons
HS Code
2902 90 80
 
Std. Transport #
4912061
 
IMO Chemical Code
17
IMO Pollution Category
A
IMO Hazard code
P