Trichloroethylene, Trichloroethene, Ethylene Trichloride, Acetylene Trichloride, Trilene, TCE, 79-01-6

TRICHLOROETHYLENE (TCE)

1. Chemical Identity and Material Classification

• Chemical Name: Trichloroethylene, Trichloroethene, 1,1,2-Trichloroethene

• Synonyms: TCE, Ethylene Trichloride, Acetylene Trichloride, Trilene, Tri-Clene, Trimar, Dow-Tri, Westrosol, Triad

• CAS Number: 79-01-6

• Molecular Formula: C₂HCl₃

• Molecular Weight: 131.39 g/mol

• EC Number (EINECS): 201-167-4

• MDL Number: MFCD00000838

• RTECS: KX4550000

• UN Number: 1710

2. Physical Properties

2.1 General Physical Properties

2.2 Water Solubility

2.3 Organic Solvent Solubility

• Miscible with most organic solvents (ethanol, diethyl ether, acetone, chloroform, benzene)

• Immiscible with water

3. Chemical Properties

3.1 Molecular Structure

• Structure: CHCl=CCl₂ (1,1,2-Trichloroethene)

• Type: Chlorinated unsaturated hydrocarbon (alkene)

• Double bond: One carbon-carbon double bond

• Chlorine atoms: Three (two on one carbon, one on the other)

3.2 Stability and Decomposition

3.3 Chemical Reactivity

3.4 Incompatibilities

• Strong oxidizing agents (nitrates, permanganates, peroxides, chromates)

• Strong bases (KOH, NaOH) – forms explosive dichloroacetylene

• Reactive metals (Al, Mg, Ba, Li, Na, K, Ti, Zn)

• Liquid oxygen, ozone

• Barium, dinitrogen tetroxide, potassium nitrate

4. Production Methods

4.1 Dehydrochlorination of Tetrachloroethane (Primary Method)

Reaction: C₂H₂Cl₄ + Ca(OH)₂ → C₂HCl₃ + CaCl₂ + 2H₂O

Process:

1. Tetrachloroethane treated with lime or alkali in presence of water

2. Reaction produces trichloroethylene and calcium chloride

3. Distillation and purification

4.2 Ethylene Chlorination Process

Process:

1. Ethylene is chlorinated to produce tetrachloroethane

2. Tetrachloroethane is dehydrochlorinated to trichloroethylene

3. Fractional distillation for purification

5. Industrial Applications

5.1 Metal Degreasing and Cleaning (Primary Application)

5.2 Chemical Intermediate

5.3 Extraction Solvent

5.4 Dry Cleaning (Historical, Now Largely Phased Out)

5.5 Pharmaceutical and Organic Synthesis

5.6 Rubber and Polymer Processing

5.7 Textile Industry (Historical)

5.8 Pesticide and Perfume Industry

5.9 Refrigeration (Historical)

6. Toxicology and Health Hazards

6.1 Acute Toxicity

6.2 Acute Health Effects

6.3 Chronic Health Effects (Severe – Carcinogen)

6.4 Carcinogenicity Classification

6.5 Target Organs

• Kidneys (primary target)

• Liver

• Central nervous system (CNS)

• Heart

• Immune system

6.6 Mutagenicity

• Positive in some genotoxicity studies

• May cause genetic damage

7. GHS Classification

8. Occupational Exposure Limits

9. Safety Precautions and Personal Protective Equipment (PPE)

• Hazards:

  • Confirmed human carcinogen (IARC Group 1)

  • Flammable – flash point 12.1°C

  • Vapors are heavier than air and may travel to ignition sources

  • Decomposes to toxic phosgene and HCl upon heating

  • CNS depressant – causes drowsiness and dizziness

• PPE (mandatory):

  • Chemical-resistant gloves (PVA, Viton, or butyl rubber – do not use neoprene or nitrile for prolonged contact)

  • Chemical splash goggles (EN 166) or full face shield

  • Protective clothing (chemical-resistant)

  • Respiratory protection: Supplied-air respirator or SCBA for high concentrations; organic vapor cartridge (Type A) for low concentrations

• Engineering controls:

  • Local exhaust ventilation (LEV) mandatory

  • Enclosed processes where possible

  • Eyewash stations and safety showers

  • Explosion-proof electrical equipment

• Fire protection:

  • Use CO₂, dry chemical, or alcohol-resistant foam (water spray may spread fire)

  • Do NOT use water jet (may spread vapor)

• First aid:

  • Inhalation: Remove to fresh air; if breathing difficulty, give oxygen; if stopped, give artificial respiration; seek immediate medical attention

  • Eye contact: Rinse with water for 15 minutes; seek medical attention

  • Skin contact: Remove contaminated clothing; wash with soap and water; seek medical attention

  • Ingestion: Do NOT induce vomiting; aspiration hazard; seek immediate medical attention

10. Environmental Fate

10.1 Ecotoxicity

Hazard classification: H411 – Toxic to aquatic life with long-lasting effects

11. Storage and Handling

11.1 Storage Conditions

11.2 Shelf Life

11.3 Container Materials

12. Transport Information

13. Regulatory Status (Critical – Highly Regulated)

Phase-out and Restrictions:

• EU: Use restricted under REACH; many uses banned (e.g., metal degreasing phased out in many member states)

• USA: Use decreasing; subject to EPA regulations; many states have restricted use

• California: Listed under Proposition 65; strict exposure controls required

14. Synonyms and Common Names

• English: Trichloroethylene, TCE, Ethylene trichloride, Acetylene trichloride, Trichloroethene, 1,1,2-Trichloroethene, Tri, Trilene, Trimar, Dow-Tri, Westrosol

• French: Trichloroéthylène

• German: Trichlorethylen

• Spanish: Tricloroetileno

• Turkish: Trikloroetilen, TCE

15. History and Current Status

• Historical uses: Metal degreasing, dry cleaning, anesthetic (Trilene), refrigerant, coffee decaffeination, food extraction

• Current status:

  • Metal degreasing: Decreasing; replaced by other solvents (HFE, nPB, aqueous cleaning)

  • Chemical intermediate: Still used for HFC-134a production (phasing down)

  • Dry cleaning: Largely replaced by perchloroethylene (also being phased out)

  • Banned in many applications due to carcinogenicity

16. Why Was TCE Used? (Historical Advantages – Not Recommended)

Current Disadvantages (Why Avoid):

• Confirmed human carcinogen (IARC Group 1)

• Toxic to kidneys and liver

• Neurotoxic

• Environmental contaminant (persistent in groundwater)

• Flammable (flash point 12.1°C)

• Decomposes to phosgene (toxic gas)

• Heavily regulated

17. Alternatives to TCE

18. Environmental Contamination (Superfund)

TCE is one of the most common groundwater contaminants at Superfund sites in the United States:

• Primary sources: Metal degreasing operations, dry cleaners, industrial waste disposal

• Typical contaminant levels: ppb to ppm range

• Cleanup technologies: Air stripping, activated carbon, bioremediation, chemical oxidation, pump-and-treat

19. Hazard Summary

20. Summary Table – Key Specifications at a Glance

CRITICAL SAFETY NOTICE: Trichloroethylene (TCE) is classified as IARC Group 1 – Carcinogenic to humans (causes kidney cancer, non-Hodgkin lymphoma, and liver cancer). It is a confirmed human carcinogen, neurotoxin, hepatotoxin, and nephrotoxin. Use is heavily restricted in many jurisdictions. Do not use without comprehensive risk assessment, engineering controls (local exhaust ventilation), personal protective equipment, and medical surveillance. Alternative solvents should be considered wherever possible.

This TDS is prepared in compliance with ISO 11014-1 format and is intended for industrial hygiene professionals, environmental engineers, chemical engineers, safety professionals, and procurement specialists. This material is NOT recommended for new applications due to its carcinogenicity and regulatory restrictions. Safety Data Sheets (SDS), exposure monitoring protocols, and regulatory compliance guidance are available upon request.