p-Xylene CAS#106-42-3
1. Key Chemical Intermediate: Essential for producing terephthalic acid (PTA), dimethyl terephthalate (DMT), and polyethylene terephthalate (PET), crucial for polyester production.
2. Versatile Solvent: Used in various industries, including pharmaceuticals, fragrances, and inks, due to its excellent solvent properties.
3. Efficient Production Process: Produced through efficient methods like toluene disproportionation and xylene isomerization, enhancing industrial scalability.
4. Physical Stability: Stable under normal conditions with low water solubility, making it suitable for diverse industrial applications.
Paraxylene is a key organic chemical intermediate, primarily used in the production of terephthalic acid (PTA), dimethyl terephthalate (DMT), and polyethylene terephthalate (PET), which is further processed into polyester. It also serves as a solvent and a raw material for manufacturing products in industries such as pharmaceuticals, fragrances, inks, and more.
Currently, China is the world’s largest producer and consumer of paraxylene. Initially, paraxylene was derived from petroleum aromatics obtained through the catalytic reforming of naphtha. However, with the growth of the petrochemical and coal coking industries, the aromatics conversion process has become the most efficient and direct method of producing paraxylene. In industrial settings, toluene and C9 aromatics are commonly used as feedstocks to produce paraxylene through various processes such as toluene disproportionation, transalkylation, xylene isomerization, toluene-methanol alkylation, and adsorption separation.
Parameters
Melting point | 12-13 °C (lit.) |
Boiling point | 138 °C (lit.) |
density | 0.861 g/mL at 20 °C (lit.) |
vapor density | 3.7 (vs air) |
vapor pressure | 9 mm Hg ( 20 °C) |
refractive index | n20/D 1.495(lit.) |
Fp | 77 °F |
storage temp. | Store at +5°C to +30°C. |
solubility | water: soluble0.2g/L |
form | Liquid |
pka | >15 (Christensen et al., 1975) |
color | Colorless |
Relative polarity | 0.074 |
Odor | Like benzene; characteristic aromatic. |
Odor Threshold | 0.058ppm |
explosive limit | 1.1-7%(V) |
Water Solubility | Miscible with alcohol, ether, acetone, benzene and chloroform. Immiscible with water. |
λmax | λ: 294 nm Amax: 1.00 |
Merck | 14,10081 |
BRN | 1901563 |
Henry's Law Constant | 16.1 at 45.00 °C, 18.6 at 50.00 °C, 20.3 at 55.00 °C, 23.4 at 60.00 °C, 30.5 at 70.00 °C (static headspace-GC, Park et al., 2004) |
Exposure limits | TLV-TWA100 ppm (～434 mg/m3) (ACGIH, MSHA, and OSHA); STEL 150 ppm (～651 mg/m3) (ACGIH); ceiling 200 ppm/ 10 min (NIOSH); IDLH 1000 ppm (NIOSH). |
Dielectric constant | 2.6（20℃） |
Stability: | Stable. Incompatible with oxidizing agents. Hygroscopic. Flammable. |
InChIKey | URLKBWYHVLBVBO-UHFFFAOYSA-N |
LogP | 3.16 at 20℃ |
Surface tension | 28.11mN/m at 298.15K |
CAS DataBase Reference | 106-42-3(CAS DataBase Reference) |
EPA Substance Registry System | p-Xylene (106-42-3) |
Safety Information
Hazard Codes | Xn,T,F |
Risk Statements | 10-20/21-38-39/23/24/25-23/24/25-11 |
Safety Statements | 25-45-36/37-16-7 |
RIDADR | UN 1307 3/PG 3 |
OEB | A |
OEL | TWA: 100 ppm (435 mg/m3), STEL: 150 ppm (655 mg/m3) |
WGK Germany | 2 |
RTECS | ZE2625000 |
Autoignition Temperature | 984 °F |
TSCA | Yes |
HazardClass | 3 |
PackingGroup | III |
HS Code | 29024300 |
Hazardous Substances Data | 106-42-3(Hazardous Substances Data) |
Toxicity | LD50 orally in Rabbit: 3910 mg/kg |
