Trichloroethylene Trichloroethylene
Structural formula
| Business number | 01P3 |
|---|---|
| Molecular formula | C2HCl3 |
| Molecular weight | 131.39 |
| label |
trichloroethylene, 1,1,2-trichloroethylene, 1,1,2-Trichloroethylene, Triclene, Aliphatic halogenated derivatives |
Numbering system
CAS number:79-01-6
MDL number:MFCD00000838
EINECS number:201-167-4
RTECS number:KX4550000
BRN number:1736782
PubChem number:24863022
Physical property data
1. Properties: Colorless and transparent liquid with a chloroform-like odor. [1]
2. Melting point (℃): -84.7~-73[2]
3. Boiling point ( ℃): 87.1[3]
4. Relative density (water=1): 1.46 (20℃)[4]
5. Relative vapor density (air=1): 4.54[5]
6. Saturated vapor pressure (kPa): 7.87 (20℃)[ 6]
7. Heat of combustion (kJ/mol): -961.4[7]
8. Critical temperature (℃): 299[8]
9. Critical pressure (MPa): 5.02[9]
10. Octanol/water Distribution coefficient: 2.42[10]
11. Flash point (℃): 32[11]
12. Ignition temperature (℃): 420[12]
13. Explosion limit (%): 90.0[13]
14. Lower explosion limit (%): 12.5[14]
15. Solubility: insoluble in water, soluble in ethanol and ether, miscible in most organic solvents. [15]
16. Viscosity (mPa·s, 20ºC): 0.58
17. Flash point (ºC, in air): 425
18. Ignition point (ºC, in oxygen): 396
19. Heat of evaporation (KJ/mol, b.p.): 31.49
20. Heat of formation (KJ/mol , 25ºC, gas): 5.86
21. Specific heat capacity (KJ/(kg·K), 20ºC, constant pressure): 0.93
22. Electrical conductivity (S/m): 8×10-12
23. Thermal conductivity (W/(m·K)): 0.1386
24. Volume expansion coefficient (K-1,0~40ºC): 0.00117
25. Solubility parameter (J·cm-3)0.5: 18.760
26.van der Waals area (cm2·mol-1): 7.130×109
28. van der Waals volume (cm3·mol-1): 49.580
29. Liquid phase standard claims heat ( Enthalpy) (kJ·mol-1): -45.1
30. Liquid phase standard hot melt (J·mol-1·K-1): 123.7
31. Gas phase standard claims heat (enthalpy) (kJ·mol-1): -9.6
32. Gas phase standard entropy (J·mol-1·K-1): 325.20
33. Gas phase standard formation free energy (kJ·mol -1): 16.1
34. Gas phase standard hot melt (J·mol-1·K-1) :80.25
Toxicological data
1. Acute toxicity[16]
LD50: 2402mg/kg (mouse oral)
LC50 : 137752mg/m3 (rat inhalation, 1h); 45292mg/m3 (mice inhalation, 4h)
2. Irritation[17]
Rabbit transdermal: 500mIn the presence of alkaline alkalis, dehydrochlorination reaction easily occurs to generate dichloroacetylene. Dichloroacetylene spontaneously ignites and explodes in the air. Sodium carbonate and liquid ammonia do not react with trichlorethylene under normal conditions. Metal aluminum, especially powdered metal aluminum, can promote the decomposition of trichlorethylene without stabilizers, generate hydrogen chloride, and at the same time undergo intense explosive decomposition or carbonization. The reaction first generates aluminum trichloride, which acts as a Friedel Crafts catalyst to promote the condensation reaction of trichlorethylene to generate pentachlorobutadiene, which is further condensed into resin and tar. In the presence of aluminum trichloride, trichloroethylene reacts with chloroform to produce 1,1,1,2,3,3-hexachloropropane. Reacts with carbon tetrachloride to produce 1,1,1,2,3,3,3-heptachloropropane. In the presence of peroxide, such as benzoyl peroxide, it is heated to 150~200°C under pressure to obtain dimers and trimers of trichlorethylene. Under the catalysis of ferric chloride, it can be easily chlorinated to produce pentachloroethane and hexachloroethane.
3. Stability[28] Stable
4. Incompatible substances[29] Strong oxidizing agent, strong reducing agent, strong alkali, aluminum, magnesium
5. Conditions to avoid contact [30] Light, ultraviolet light
6. Polymerization hazard[31] Polymerization
7. Decomposition products [32] Hydrogen chloride
Storage method
Storage Precautions[33] Store in a cool, ventilated warehouse. Keep away from fire and heat sources. The storage temperature does not exceed 32°C and the relative humidity does not exceed 80%. The packaging must be sealed and must not come into contact with air. They should be stored separately from oxidants, reducing agents, alkalis, metal powders, and food chemicals, and avoid mixed storage. It should not be stored in large quantities or for long periods of time. Equipped with the appropriate variety and quantity of fire equipment. The storage area should be equipped with emergency release equipment and suitable containment materials.
Synthesis method
1. Acetylene method This method uses acetylene and chlorine generated from calcium carbide as raw materials, carbon tetrachloride as diluent, and ferric chloride as catalyst to synthesize 1,1,2,2-tetrachloroethane in liquid phase, and then Add lime milk for dehydrochlorination to obtain crude trichlorethylene. After crude distillation and rectification, the product is obtained. Because acetylene is expensive, most use the ethylene method. 
2. Ethylene direct chlorination method via direct chlorine The mixture of tetrachloroethane and pentachloroethane is obtained, and trichlorethylene and tetrachlorethylene are produced by gas phase cracking. The main reaction formula is as follows:
3. Ethylene oxide Chlorination method This method uses ethylene, oxygen (or air), and chlorine as raw materials, and undergoes catalytic chlorination and oxidation to obtain trichlorethylene products, and tetrachlorethylene can also be obtained. The main reaction formula is as follows:
Purpose
1. Trichlorethylene is mainly used as a metal degreasing agent and a dry cleaning agent for wool and fabrics. It is an excellent solvent and can be used as a substitute for benzene and gasoline. Solvent for resin, asphalt, coal tar, cellulose acetate, nitrocellulose, rubber and paint, etc. It is used as an anesthetic in medicine and as a raw material for the synthesis of monochloroacetic acid in pesticides. Industrially used for metal cleaning (thorough degreasing) and fiber degreasing, and as an extraction agent for fats, oils, paraffin, etc. Taking advantage of its strong dissolving power, it is often used to remove difficult-to-remove dirt, such as semi-hardened varnish, coating polishing agent, and thicker flux. Also used in extractants, solvents and low-temperature heat transfer oil media. It is also used as paint thinner, paint stripper, refrigerant, alcohol dehydration distillation additive, anesthetic, sedative, insecticide, fungicide, fumigant and organic synthesis intermediate. As raw material intermediates, it can be used to produce tetrachloroethylene, chloroacetic acid, dichloroacetyl chloride, octachlorodipropyl ether, HCFC—-123, HCFC—124, HFC—125, HFC—134a, etc. .
2. Used as a solvent for degreasing metal surfaces, dry cleaning clothes, extracting plant and mineral oils, preparing drugs, organic synthesis, and dissolving greases, rubbers, resins, and alkaloids. It is widely used in the fields of degreasing, freezing, pesticides, spices, rubber industry, washing fabrics and other fields.
3. It is an excellent solvent and a good substitute for benzene and gasoline. Used as a solvent for adhesives, a thinner for paint, a paint stripper, an alcohol dehydration distillation additive, an anesthetic, a refrigerant, a sedative, an insecticide, a fungicide, a fumigant, and also used as a metal degreasing agent and fat, Extractants for oils and paraffins, and organic synthesis intermediates, etc.
4. Used as a solvent for degreasing, freezing, pesticides, spices, rubber industry, washing fabrics, etc. [34]
