1,2,4-Trichlorobenzene
A high-purity chlorinated aromatic supplied as a high-boiling process solvent, dye carrier, and intermediate for herbicide and dye manufacture.
What is 1,2,4-Trichlorobenzene?
1,2,4-Trichlorobenzene — 124TCB — is a colourless liquid with three chlorine atoms arranged asymmetrically around the ring. It is the dominant isomer produced when benzene or dichlorobenzene is further chlorinated.
Its value comes from a rare combination: a high boiling point, thermal stability, very low water solubility, and the ability to dissolve materials that most solvents will not touch. That profile made it the standard carrier for dyeing polyester and a workhorse high-temperature reaction solvent.
At Chelora Chemicals, 124TCB is distilled with isomer content and moisture held to specification. Because the product is restricted in several jurisdictions, we supply it only for permitted uses such as synthesis intermediates and closed-system process applications.
- Appearance
- Clear, colourless liquid
- Odour
- Characteristic aromatic
- Solubility
- Practically insoluble in water; miscible with organic solvents
- Function
- Process solvent / chemical intermediate
- Grade
- Technical
Formula diagram
Benzene ring chlorinated at the 1, 2 and 4 positions
- Molecular formulaC6H3Cl3
- Molecular weight181.45 g/mol
- IUPAC name1,2,4-Trichlorobenzene
- Functional groupsAryl chloride
- CAS number120-82-1
Technical product information
Standard specification for Chelora Chemicals' technical grade 1,2,4-Trichlorobenzene. Custom-grade and bulk specifications are available on request.
| Chemical name | 1,2,4-Trichlorobenzene |
|---|---|
| Synonyms | 124TCB, unsym-Trichlorobenzene, 1,2,4-TCB |
| CAS number | 120-82-1 |
| Molecular formula | C6H3Cl3 |
| Molecular weight | 181.45 g/mol |
| Assay (purity) | ≥ 99.5% |
| Appearance | Clear, colourless liquid |
| Density (20°C) | 1.452–1.463 g/cm³ |
| Boiling point | 213–214°C |
| Melting point | 17°C |
| Flash point | 105°C (closed cup) |
| Isomer content | ≤ 0.5% |
| Moisture | ≤ 0.05% |
| Packaging | 250 kg drums, 1000 kg IBC, ISO tank |
| Shelf life | 24 months in sealed original packaging |
Applications of 1,2,4-Trichlorobenzene
Dye carrier
Used as a carrier that swells polyester fibre and allows disperse dyes to penetrate at accessible temperatures.
High-temperature reaction solvent
Provides a stable, high-boiling medium for reactions run well above the range of common solvents.
Herbicide intermediates
Serves as a starting material in chlorinated aromatic crop-protection synthesis.
Dye & pigment intermediates
Nitrated or aminated to build chlorinated aromatic colour intermediates.
Dielectric & heat transfer fluids
Applied in specialty electrical and heat transfer formulations where thermal stability is required.
Industrial cleaning
Used in closed-system degreasing and process cleaning applications for difficult residues.
Why choose Chelora Chemicals
Every batch of 1,2,4-Trichlorobenzene is manufactured, tested, and documented to a standard that formulators and process chemists can build on with confidence — from first sample to full production volume.
Consistent purity
Assay controlled at ≥99.5% with isomer content and moisture verified before dispatch.
Full documentation
COA, SDS, and regulatory data supplied with every shipment.
Flexible volumes
From 250 kg drums to IBC and ISO tank supply.
Technical support
Process, handling, and compliance guidance from our chemistry team.
Storage and guidelines
- 01Store in tightly sealed original containers in a cool, dry, well-ventilated store.
- 02Keep away from heat, sparks, and open flame; the product is combustible above its flash point.
- 03Protect from low temperatures — the product solidifies near 17°C and requires gentle warming to re-liquefy.
- 04Segregate from strong oxidising agents, strong bases, and active metals such as aluminium powder.
- 05Use compatible containers: carbon steel, stainless steel, or lined steel; check elastomer compatibility for seals.
- 06Bund all bulk storage and prevent any release to drains, surface water, or soil.
Handling precautions
124TCB is harmful if swallowed or inhaled, causes skin and eye irritation, and is very toxic to aquatic life with long-lasting effects. It is for industrial use by trained personnel only.
Use closed transfer and local exhaust ventilation. Vapour concentrations rise quickly in heated operations, and the product has poor warning properties at low levels.
Chlorinated aromatics can decompose at very high temperature or in a fire to produce hydrogen chloride and other hazardous combustion products. Fire-fighters require full breathing apparatus.
In several jurisdictions the supply and use of 1,2,4-trichlorobenzene is restricted to specific permitted uses such as synthesis intermediates and closed-system applications. Confirm your national requirements before ordering.
Refer to the full Safety Data Sheet for exposure limits, spill containment, environmental precautions, and first-aid measures before use.
Frequently asked questions
What is 1,2,4-Trichlorobenzene used for?
Historically as a dye carrier for polyester and as a high-boiling process solvent, plus as an intermediate in herbicide and dye synthesis and in dielectric and heat transfer fluids. Several of these uses are now restricted in some markets.
Why is 124TCB the isomer that gets produced commercially?
Chlorinating benzene or dichlorobenzene favours the 1,2,4 arrangement over the symmetrical 1,2,3 and 1,3,5 isomers on both electronic and statistical grounds, so it dominates the product mix and is separated by distillation.
How does a dye carrier work?
Polyester fibre is tightly packed and resists dye penetration below its glass transition. A carrier swells the fibre and increases chain mobility, letting disperse dye molecules diffuse in at temperatures that ordinary equipment can reach.
Is 124TCB regulated?
In several jurisdictions, yes. It is restricted to specific permitted uses such as chemical synthesis intermediates and closed-system process solvents, with general and consumer uses prohibited. Confirm the rules that apply to your intended use before ordering.
Why does the product solidify in cold storage?
Its melting point is 17°C, so drums and lines can set in an unheated store during winter. Re-liquefy with gentle, controlled warming rather than direct flame or localised heating.
Is it soluble in water?
Practically insoluble, and it is denser than water, so a spill will sink rather than float. It is miscible with most organic solvents including alcohols, ethers, and aromatic hydrocarbons.
What purity do you supply?
Standard technical grade is supplied at a minimum assay of 99.5% with isomer content at or below 0.5% and moisture at or below 0.05%. Tighter specifications can be produced to order.
What packaging sizes are available?
250 kg drums, 1000 kg IBCs, and ISO tanks. Supply is subject to confirmation of the intended end use where regulatory restrictions apply.
What materials of construction are suitable?
Carbon steel, stainless steel, and lined steel are used in normal service. Elastomer seals should be checked for compatibility, since chlorinated aromatics swell many common rubbers.
Why is aquatic toxicity emphasised for this product?
It is very toxic to aquatic organisms with long-lasting effects and does not break down quickly in the environment. Bunding, containment, and drain protection are the primary controls at any handling site.
Do you provide a Certificate of Analysis?
Yes. Every batch is dispatched with a Certificate of Analysis and Safety Data Sheet covering assay, isomer content, density, moisture, and appearance.