Meta-Xylene
The most abundant xylene isomer at equilibrium and the hardest to separate. Feedstock for isophthalic acid, MXDA and nylon-MXD6 barrier resin.
Molecular Structure
What is Meta-Xylene?
Meta-xylene is the 1,3-disubstituted xylene isomer, with methyl groups separated by one ring carbon. It is a clear liquid boiling at 139.1 °C.
Meta is the thermodynamically favoured isomer: at typical isomerisation equilibrium a mixed xylene stream is roughly half m-xylene, with the ortho and para isomers making up the rest. That abundance is offset by the difficulty of isolating it, since m-xylene boils less than 1 °C above p-xylene and cannot be distilled away from it.
Recovery therefore uses selective adsorption on molecular sieves or complexation with HF–BF₃. Much of the m-xylene in an aromatics complex is simply isomerised back to p-xylene; the volume that is recovered as a product goes to isophthalic acid and to m-xylylenediamine.
Chelora supplies meta-xylene recovered by selective adsorption to ≥99.0 wt%, with para- and ortho-isomer content controlled for isophthalic acid and MXDA service. Available in ISO tanks, road tankers and drums.
Quick Reference
Key Physical & Chemical Properties
Structure & Bonding
Meta substitution places the methyl groups 1,3 on the ring. Oxidation gives isophthalic acid, whose kinked geometry is exactly why it is added to polyester chains to disrupt crystallinity.
Skeletal structure — methyls at C-1 and C-3 (meta)
Structural Identity
- IUPAC Name1,3-Dimethylbenzene
- Molecular FormulaC₈H₁₀
- Molecular Weight106.17 g/mol
- Hybridisationsp² ring, sp³ methyl carbons
- Substitution pattern1,3-disubstituted (meta)
- Bond lengths1.39 Å ring C–C; 1.50 Å C–CH₃
- GeometryPlanar ring, C₂ᵥ symmetry
- Isomer separationSelective adsorption or HF–BF₃ complexation
- CAS Number108-38-3
- InChI KeyIVSZLXZYQVIEFR-UHFFFAOYSA-N
Product Specifications
Chelora supplies Meta-Xylene in standard and custom grades. Contact us for specification sheets tailored to your process.
| Chemical name | Meta-Xylene (m-xylene) |
|---|---|
| CAS Number | 108-38-3 |
| Molecular formula | C₈H₁₀ |
| Molecular weight | 106.17 g/mol |
| Purity (standard grade) | ≥ 99.00 wt% |
| Purity (high-purity grade) | ≥ 99.50 wt% |
| p-Xylene (max) | ≤ 0.50 wt% |
| o-Xylene (max) | ≤ 0.30 wt% |
| Ethylbenzene (max) | ≤ 0.30 wt% |
| Non-aromatics (max) | ≤ 0.20 wt% |
| Total sulfur (max) | ≤ 1.0 ppm wt |
| Water (max) | ≤ 200 ppm wt |
| Colour | ≤ 20 Pt-Co (Hazen) |
| Distillation range | 138.5 – 140.0 °C |
| Density | 0.861 – 0.867 g/cm³ at 20 °C |
| Flash point | 27 °C (closed cup) |
| Autoignition temperature | 527 °C |
| Flammable limits | 1.1 – 7.0% v/v in air |
| UN Number | UN 1307 |
| IMDG / ADR Class | Class 3 (Flammable Liquid), PG III |
Downstream Applications & Derivatives
Key derivative chains and industrial uses of Meta-Xylene.
Isophthalic Acid
Liquid-phase air oxidation gives isophthalic acid (PIA), the main m-xylene derivative. Its kinked geometry disrupts polyester crystallinity, which is why it is copolymerised into PET bottle resin.
Nylon-MXD6 Barrier Resin
Via m-xylylenediamine and adipic acid, MXD6 is a high gas-barrier polyamide used as a middle layer in multilayer PET bottles and in food packaging film.
MXDA Epoxy Curing Agents
Ammoxidation to isophthalonitrile then hydrogenation gives m-xylylenediamine — a fast, rigid curing agent for epoxy coatings, flooring and civil-engineering adhesives.
Unsaturated Polyester & Powder Coatings
Isophthalic acid grades of UPR give better hydrolytic and chemical resistance for gelcoats, pipe and tank linings, and IPA-based polyesters are standard in weatherable powder coatings.
Isomerisation to Para-Xylene
Inside an aromatics complex, m-xylene is recycled through an isomerisation unit to re-equilibrate the C₈ stream and lift overall para-xylene yield.
Agrochemical & Dye Intermediates
Routes to 2,4- and 2,6-dimethylaniline, isophthalonitrile and m-toluic acid supply fungicides, herbicides, insect repellents, dyes and UV absorbers.
Why source Meta-Xylene through Chelora Petrochem?
Verified Origin
Full origin certification and asset-backed supply chain documentation — no grey-market supply.
Grade Flexibility
Standard and high-purity grades available. Para- and ortho-isomer content and ethylbenzene can be tightened for oxidation or amination service.
Full Documentation
CoA, SDS, UN transport docs, REACH compliance, and destination-market certificates with every shipment.
Logistics Support
Experienced in bulk aromatic liquid logistics — ISO tanks, road tankers, and drums with nitrogen blanketing where required, for Indian and international delivery.
Storage & Handling Guidelines
Always refer to the full SDS before handling. The following is a summary of key requirements.
- Store in a bunded, well-ventilated, dedicated area away from ignition sources, heat and direct sunlight.
- All electrical equipment in storage and transfer areas must be ATEX/IECEx rated for the applicable zone.
- Bond and earth tanks, tankers, drums and hoses before every transfer — aromatic liquids accumulate static readily.
- Keep away from strong oxidisers, acids and halogens; use PTFE or Viton seals, as many elastomers swell in aromatics.
- Maintain a nitrogen blanket on bulk storage where the tank headspace can sit inside the flammable range.
- Fit fixed flammable-vapour detection with audible and visual alarms set below the LEL in enclosed storage and pump areas.
- Provide local exhaust ventilation at sampling, drumming and loading points, and monitor personal exposure against the OEL.
- Keep foam, dry chemical or CO₂ media available for firefighting — water jets spread the burning liquid.
Hazard Summary
Classification: Flam. Liq. 3 (H226) · Acute Tox. 4 dermal/inhalation (H312, H332) · Skin Irrit. 2 (H315) · Eye Irrit. 2 (H319) · STOT SE 3 (H335) · STOT RE 2 (H373) · Asp. Tox. 1 (H304).
Health: Causes central nervous system depression at elevated vapour concentrations, and defatting dermatitis on repeated skin contact. Aspiration into the lungs can cause chemical pneumonitis — never induce vomiting.
Exposure limits: ACGIH TLV 100 ppm 8-h TWA with a 150 ppm STEL; EU IOELV 50 ppm TWA / 100 ppm STEL with a skin notation; OSHA PEL 100 ppm TWA. Confirm the limit in force in your jurisdiction.
Flammability: Flash point 27 °C — close to ambient in warm climates. Treat storage and pump areas as potentially flammable atmospheres and keep tanks out of direct sun.
PPE minimum: Chemical splash goggles, nitrile or Viton gloves, flame-retardant antistatic clothing, and organic-vapour respiratory protection where ventilation cannot hold exposure below the limit.
Consult the full SDS for exposure limits, spill containment, emergency response, and disposal before any use.
Frequently Asked Questions
Technical and commercial questions about Meta-Xylene sourcing and specifications.
What is meta-xylene used for?
The largest outlet is oxidation to isophthalic acid, used to modify PET bottle resin and to make corrosion-resistant unsaturated polyester and powder-coating resins. The second major route is m-xylylenediamine, which gives rigid epoxy curing agents and nylon-MXD6 gas-barrier resin. Smaller volumes go to dimethylaniline agrochemical intermediates, dyes and UV absorbers.
Why is meta-xylene difficult to separate?
Meta-xylene boils at 139.1 °C and para-xylene at 138.4 °C — under 1 °C apart, which rules out practical distillation. Their freezing points are far apart, but crystallisation is normally used to recover the para isomer rather than the meta. Commercial m-xylene is therefore recovered by selective adsorption on molecular sieves or by complexation with HF–BF₃, which exploits m-xylene's higher basicity.
Why is m-xylene the most abundant isomer?
Meta is the thermodynamically most stable of the three isomers, so a xylene stream that has passed through an isomerisation catalyst equilibrates to roughly 50% meta with the remainder split between ortho and para. Because para-xylene is the isomer in demand, most aromatics complexes continuously extract para and recycle the meta-rich raffinate back to isomerisation.
What is the difference between isophthalic and terephthalic acid?
Both are benzenedicarboxylic acids, but isophthalic acid (from m-xylene) has its acid groups 1,3 on the ring while terephthalic acid (from p-xylene) has them 1,4. The linear terephthalate unit packs into a crystalline polyester; the kinked isophthalate unit disrupts that packing. That is precisely why a few percent of isophthalic acid is copolymerised into PET bottle resin — it slows crystallisation and improves clarity and stretch-blow performance.
How should meta-xylene be stored?
As a Class 3 flammable liquid with a 27 °C flash point, in a bunded, ventilated area away from ignition sources and direct sunlight, with bonding and earthing on all transfers and ATEX-rated electrical equipment. Nitrogen blanketing is normal on bulk storage. Refer to the full SDS before handling.
What documentation does Chelora provide?
Every shipment includes a Certificate of Analysis covering purity, isomer distribution, ethylbenzene, non-aromatics, sulfur, water, colour and distillation range; a Safety Data Sheet (GHS/REACH); UN 1307 Class 3 PG III transport documentation; an origin certificate; and any destination-market certificates required.
Request a quote or specification sheet
Talk to Chelora's sourcing team about Meta-Xylene grade, volume, logistics, documentation, and lead times. We respond within one business day.
