o-Xylene

  • 1,2-Dimethylbenzene
  • o-Dimethyl benzene
  • 1,2-Xylene
  • o-Xylol
Formula
C6H4(CH3)2
Structure
Description
Clear, colorless liquid with a characteristic aromatic odor.
Uses
Raw material for production of plasticizers, alkylated resins, glass-enforced polyesters, manufacture of phthalic anhydride.

Registry Numbers and Inventories.
CAS
95-47-6
EC (EINECS/ELINCS)
202-422-2
EC Index Number
601-038-00-6
EC Class
Flammable; Harmful; Irritant
R 10 20/21 38
RTECS
ZE2450000
RTECS class
Tumorigen; Reproductive Effector; Human Data
UN (DOT)
1307
Merck
12,10214
Beilstein/Gmelin
1815558
Beilstein Reference
4-05-00-00917
RCRA
U239
Swiss Giftliste 1
G-4658
Canada DSL/NDSL
DSL
US TSCA
Listed
Austrailia AICS
Listed
New Zealand
Listed
Japan ENCS (MITI)
Listed
Korea ECL
Listed

Properties.
Formula
C8H10
Formula mass
106.17
Melting point, °C
-25
Boiling point, °C
144
Vapor pressure, mmHg
6 (25 C)
Vapor density (air=1)
3.7
Saturation Concentration
0.66% (20 C)
Evaporization number
1 (butyl acetate=1)
Odor Threshold Odor threshold 1.8 ppm in water
Critical temperature
359
Critical pressure
36.0
Density
0.880 g/cm3 (20 C)
Solubility in water
0.2 g/L
Viscosity
0.812 cp (20 C)
Surface tension
29.76 g/s2 at 25 C
Refractive index
1.5055 (20C)
Dipole moment
0.45 D (20 C)
Dielectric constant
2.5 (30 C)
Partition coefficient, pKow
3.12
Heat of fusion
13.6 kJ/mol
Heat of vaporization
43.4 kJ/mol
Heat of combustion
-4553 kJ/mol

Hazards and Protection.
Storage
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.
B2 D2B
Handling
Wash thoroughly after handling. Remove contaminated clothing and wash before reuse. Use with adequate ventilation. Ground and bond containers when transferring material. Use spark-proof tools and explosion proof equipment. Avoid contact with skin and eyes. Empty containers retain product residue, (liquid and/or vapor), and can be dangerous. 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 half-face organic vapor respirator may be worn for up to ten times the exposure limit, or the maximum use concentration specified by the appropriate regulatory agency or respirator supplier, whichever is lowest. A full-face piece organic vapor respirator may be worn up to 50 times the exposure limit, or the maximum use concentration specified by the appropriate regulatory agency or respirator supplier, whichever is lowest. For emergencies or instances where the exposure levels are not known, use a full-face piece positive-pressure, air-supplied respirator.
Small spills/leaks
Avoid runoff into storm sewers and ditches which lead to waterways. Clean up spills immediately, using the appropriate protective equipment. Wear a self contained breathing apparatus and appropriate Personal protection. (See Exposure Controls, Personal Protection section). Scoop up with a nonsparking tool, then place into a suitable container for disposal. Remove all sources of ignition. Absorb spill using an absorbent, non-combustible material such as earth, sand, or vermiculite. Provide ventilation.
Disposal code
1
Stability
Stable at room temperature in closed containers under normal storage and handling conditions.
Incompatibilities
Strong acids, strong oxidizers.
Decomposition
Carbon monoxide, carbon dioxide, hydrocarbons.

Fire.
Flash Point,°C
30
Autoignition, °C
465
Upper exp. limit, %
7.60
Lower exp. limit, %
1.0
Fire fighting
Wear a self-contained breathing apparatus in pressure-demand, MSHA/NIOSH (approved or equivalent), and full protective gear. 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. Extinguishing media: For small fires, use dry chemical, carbon dioxide, water spray or alcohol-resistant foam. Water may be ineffective. For large fires, use water spray, fog or alcohol-resistant foam. Do NOT use straight streams of water.
Fire potential
Quite flammable, combustion possible. Heavy vapors may travel along ground to ignition source.
Hazards
Vapor is heavier than air and may travel considerable distance to a source of ignition and flash back. Containers may explode when heated.
Combustion products
Fire will produce irritating, corrosive and/or toxic gases.
Health
2
 
Flammability
3
 
 
Reactivity
0
 

Health.
Exposure limit(s)
OSHA PEL: TWA 100 ppm (435 mg/m3) NIOSH REL: TWA 100 ppm (435 mg/m3) ST 150 ppm (655 mg/m3) NIOSH IDLH: 900 ppm
Poison_Class
4
Exposure effects
Chronic exposure to organic solvents has been associated with various neurotoxic effects including permanent brain and nervous system damage. Prolonged or repeated skin contact may cause defatting and dermatitis.
   Ingestion
May cause central nervous system depression, kidney damage, and liver damage. Symptoms may include: headache, excitement, fatigue, nausea, vomiting, stupor, and coma. Causes gastrointestinal irritation with nausea, vomiting and diarrhea. Harmful or fatal if swallowed
   Inhalation
Inhalation of high concentrations may cause central nervous system effects characterized by headache, dizziness, unconsciousness and coma. Inhalation of vapor may cause respiratory tract irritation. Prolonged exposure may result in dizziness and general weakness. Irritation may lead to chemical pneumonitis and pulmonary edema. May cause liver and kidney damage.
   Skin
Exposure may cause irritation characterized by redness, dryness, and inflammation. Prolonged and/or repeated contact may cause defatting of the skin and dermatitis. Skin absorption is slight.
   Eyes
Contact with eyes may cause severe irritation, and possible eye burns.

First aid
 
   Ingestion
Do NOT induce vomiting. If victim is conscious and alert, give 2-4 cupfuls of milk or water. 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 if cough or other symptoms appear. DO NOT use mouth-to-mouth respiration.
   Skin
Immediately flush skin with plenty of soap and water for at least 15 minutes while removing contaminated clothing and shoes. Get medical aid if irritation develops or persists. Wash clothing before reuse.
   Eyes
Immediately 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
1307
Response guide
Hazard class
3
Packing Group
II; III
 
USCG CHRIS Code
XLO
 
32 Aromatic hydrocarbons
HS Code
2902 41 00
 
IMO Chemical Code
17
IMO Pollution Category
C
IMO Hazard code
P