Trichloroethylene
[CAS# 79-01-6]

Identification

• Classification: Pharmaceutical intermediate >> Heterocyclic compound intermediate >> Pyridine compound >> Fluoropyridine
• Name: Trichloroethylene
• Synonyms: 1-Chloro-2,2-dichloroethylene; 1,1-Dichloro-2-chloroethylene; 1,2,2-Trichloroethylene
• Molecular Formula: C₂HCl₃
• Molecular Weight: 131.39
• CAS Registry Number: 79-01-6
• EC Number: 201-167-4
• SMILES: C(=C(Cl)Cl)Cl

Properties

• Density: 1.462 g/mL
• Melting point: -86 °C
• Boiling point: 87 °C
• Refractive index: 1.476
• Water solubility: Slightly soluble. 0.11 g/100 mL

Safety Data

• Hazard Symbols: GHS08;GHS07 Danger
• Risk Statements: H350-H341-H336-H315-H319-H412
• Safety Statements: P203-P261-P264-P264+P265-P271-P272-P273-P280-P302+P352-P304+P340-P305+P351+P338-P318-P319-P321-P332+P317-P333+P317-P337+P317-P362+P364-P403+P233-P405-P501

Hazard Classification

Hazard	Class	Category Code	Hazard Statement
Germ cell mutagenicity	Muta.	2	H341
Carcinogenicity	Carc.	1B	H350
Skin irritation	Skin Irrit.	2	H315
Chronic hazardous to the aquatic environment	Aquatic Chronic	3	H412
Eye irritation	Eye Irrit.	2	H319
Specific target organ toxicity - single exposure	STOT SE	3	H336
Skin sensitization	Skin Sens.	1B	H317
Specific target organ toxicity - single exposure	STOT SE	3	H335
Specific target organ toxicity - repeated exposure	STOT RE	2	H373
Skin sensitization	Skin Sens.	1	H317
Eye irritation	Eye Irrit.	2A	H319

• Transport Information: UN 1710

Discovery and Applications

Trichloroethylene (TCE) is a colorless, volatile liquid with a sweet odor, known for its ability to dissolve fats and oils. The chemical formula for TCE is C2HCl3. Its discovery dates back to the mid-19th century, with the first synthesis occurring in 1864 by the German chemist Friedrich Konrad Beilstein. Initially, TCE was used primarily as a solvent for fats, oils, and waxes, but its application expanded significantly over the years.

One of the primary uses of trichloroethylene is as an industrial solvent in the manufacturing sector. It is widely employed in the degreasing of metal parts, particularly in the aerospace and automotive industries, where it helps remove grease, oil, and contaminants from machinery and components. Its effectiveness at dissolving various substances makes it invaluable for maintaining equipment and ensuring the proper functioning of machinery.

In addition to its role as a solvent, TCE is used in the production of other chemicals. It serves as an intermediate in the synthesis of various fluorinated compounds, such as hydrofluorocarbon refrigerants. Its ability to act as a building block in chemical reactions is a significant aspect of its industrial utility.

Trichloroethylene has also been utilized in the formulation of adhesives, paints, and coatings. Its quick evaporation rate helps in achieving a smooth finish, making it a preferred solvent in these applications. Moreover, TCE has found applications in the pharmaceutical industry, where it is employed as a solvent in drug formulation processes.

Despite its widespread use, trichloroethylene poses health and environmental risks. Exposure to TCE has been linked to various health issues, including respiratory problems, dizziness, headaches, and, in chronic cases, an increased risk of certain cancers. Consequently, regulatory bodies, including the U.S. Environmental Protection Agency (EPA), have established guidelines and regulations to limit exposure and ensure safe handling in industrial settings.

In conclusion, trichloroethylene is a versatile chemical with significant applications in various industries, particularly as a solvent for degreasing and in chemical synthesis. While its effectiveness makes it a valuable compound, awareness of its health and environmental impacts is essential for ensuring safe use and compliance with regulations.

References

1984. Chlorinated ethylenes: their metabolism and effect on DNA repair in rat hepatocytes. Carcinogenesis, 5(12).
DOI: 10.1093/carcin/5.12.1629

1991. Nerve function in workers with long term exposure to trichloroethene. Occupational and Environmental Medicine, 48(2).
DOI: 10.1136/oem.48.2.087

2024. Iron-Based Materials Synthesized by Mechanical Ball Milling for Environmental Contaminants Removal: Progress and Prospects. International Journal of Environmental Research, 18(5).
DOI: 10.1007/s41742-024-00671-w