Ortho-Xylene
The 1,2-dimethylbenzene isomer supplied by Chelora Chemicals — the dedicated feedstock for phthalic anhydride manufacture, which in turn supplies the plasticiser and unsaturated-polyester-resin industries — exported from Indonesia in drums or ISO tanks with full batch documentation on every shipment.
What Ortho-Xylene is, and why buyers source it
A working overview of the compound's chemistry, its role as the adjacent-substituted xylene isomer, and the grades Chelora Chemicals keeps in regular supply.
Ortho-Xylene carries its two methyl groups on adjacent ring carbons, the 1 and 2 positions. That adjacency is exactly what matters industrially: when the ring is oxidised, the two methyl groups end up close enough together to cyclise, forming the five-membered anhydride ring of phthalic anhydride — a reaction the meta and para isomers cannot undergo in the same way.
At room temperature it is a colourless, highly flammable liquid with a sweet aromatic odour, immiscible with water but miscible with most organic solvents. Among the three xylene isomers it is the easiest to isolate in high purity, since its boiling point sits several degrees clear of meta- and para-xylene, letting ordinary fractional distillation do the separation work.
Where it fits in the synthesis chain
Ortho-Xylene's dominant industrial use, by a wide margin, is as the feedstock for phthalic anhydride, produced by catalytic vapour-phase oxidation. Phthalic anhydride in turn is the key raw material for phthalate plasticisers (used in flexible PVC), unsaturated polyester and alkyd resins, and a range of dye and pigment intermediates. A smaller share is used directly as a high-boiling industrial solvent.
Grades we supply
Chelora Chemicals offers Ortho-Xylene in technical grade (≈98.5% assay) for general solvent use, and phthalic-anhydride grade (99.5%+, low in sulfur and non-aromatic impurities) for catalytic oxidation feedstock use. Both grades are supplied with a batch-wise certificate of analysis.
How Ortho-Xylene is made
An overview of the production route for orientation purposes. Our manufacturing partners' own process parameters and in-process controls are proprietary and are not disclosed beyond what is needed to interpret the certificate of analysis.
Ortho-Xylene is separated from the mixed C8 aromatic stream — itself recovered from catalytic reforming of naphtha or pyrolysis gasoline — by straightforward fractional distillation. Because ortho-xylene's boiling point (144 °C) sits several degrees above meta-xylene (139 °C) and para-xylene (138 °C), a dedicated distillation column can recover it in high purity without the crystallisation or adsorption steps needed to separate the other two isomers from each other.
Why distillation alone works for ortho-xylene
The boiling-point gap between ortho-xylene and its two close-boiling siblings is wide enough for conventional tray or packed-column distillation to achieve commercial-grade purity directly, making ortho-xylene the most straightforward and lowest-cost of the three isomers to isolate from the mixed C8 stream.
Industries and processes that use it
Ortho-Xylene is consumed overwhelmingly as the phthalic anhydride feedstock, with a smaller share used directly as an industrial solvent. The fields below account for most of the demand we see through our export desk.
Phthalic Anhydride Feedstock
Catalytically oxidised in the vapour phase to phthalic anhydride, the dominant industrial use of this isomer by a wide margin.
Plasticiser Chain (via Phthalic Anhydride)
Supplies, through phthalic anhydride, the raw material for phthalate plasticisers used to make flexible PVC products.
Unsaturated Polyester & Alkyd Resin Chain
Supplies, through phthalic anhydride, a key building block for unsaturated polyester and alkyd coating resins.
Industrial Solvent
Used directly as a high-boiling aromatic solvent in select coating, cleaning and specialty-formulation applications.
How the molecule is typically carried forward
The adjacent placement of the two methyl groups governs almost all of this molecule's further reaction chemistry. Reaction classes below account for most of the ways Ortho-Xylene is converted into a finished product or intermediate.
Catalytic Vapour-Phase Oxidation
Both methyl groups are oxidised over a vanadium pentoxide catalyst at high temperature, and the adjacent carboxylic acid groups formed immediately cyclise with loss of water to give phthalic anhydride.
Phthalic Anhydride Esterification (Plasticiser Chain)
Phthalic anhydride reacts with branched alcohols such as 2-ethylhexanol to form phthalate ester plasticisers.
Phthalic Anhydride Polycondensation (Resin Chain)
Phthalic anhydride condenses with polyols and other diacids to build unsaturated polyester and alkyd resin backbones.
Direct Side-Chain Oxidation
Selective oxidation can also be stopped at the mono-carboxylic acid stage to give o-toluic acid, a smaller-volume specialty intermediate.
Ortho-Xylene against other amines we supply
Buyers sourcing Ortho-Xylene for phthalic anhydride or solvent use often need a related xylene isomer or the parent mixed stream. A quick reference to what else is on our regular supply list.
| Product | CAS Number | Category | Notes |
|---|---|---|---|
| Ortho-Xylene | 95-47-6 | C8 aromatic isomer | The product on this page — the dedicated feedstock for phthalic anhydride. |
| Mixed Xylenes | 1330-20-7 | C8 aromatic isomer blend | The parent stream Ortho-Xylene is separated from — see its product page. |
| Para-Xylene | 106-42-3 | C8 aromatic isomer | The PET/polyester-grade sibling isomer — see its product page. |
| Meta-Xylene | 108-38-3 | C8 aromatic isomer | The isophthalic-acid-grade sibling isomer — see its product page. |
Exact physical constants and purity specifications are confirmed per batch on the certificate of analysis — treat the notes above as a sourcing guide, not a specification sheet, for products other than Ortho-Xylene.
Safety classification at a glance
Based on GHS classification as commonly listed for this substance. This is a summary for orientation only — always work from the current safety data sheet supplied with your specific batch.
Flammable liquid and vapour.
Causes skin irritation.
Causes serious eye irritation.
Harmful if inhaled.
Chemical-resistant gloves, splash goggles and suitable respiratory protection are the baseline for routine handling.
Keep away from heat, sparks and open flame; ground and bond containers during transfer.
Use only with adequate ventilation or suitable respiratory protection to limit vapour exposure.
Warning — GHS02 flammable and GHS07 harmful pictograms apply.
This compound is a flammable liquid that causes skin and serious eye irritation, and is harmful if inhaled. It must be handled with chemical-resistant gloves, splash-proof eye protection and suitable respiratory protection, and kept away from heat and open flame. Full first-aid, storage, spill and PPE guidance is in the MSDS issued with every shipment, and should be read in full before this material is handled.
Keeping it on spec between delivery and use
General storage guidance for this grade. Site-specific storage rules, segregation requirements and re-test intervals should follow your own EHS procedures and the MSDS issued with your batch.
Store in a cool, dry, well-ventilated area away from heat sources, open flame and strong oxidizing agents, in tightly closed original packaging. Ground and bond all equipment during bulk transfer. If a batch is held past its retest date, re-check assay, isomer purity and colour before use.
How it ships from Indonesia
Standard packing and export terms for this product. Confirm exact figures against your order — they vary slightly by destination and quantity.
What travels with every batch
Specification is agreed before the purchase order, not discovered on arrival. Every shipment of Ortho-Xylene leaves with a documented, checkable paper trail.
Certificate of Analysis
Batch-wise assay (by titration/GC), colour and relevant physical constants, issued against the agreed specification so your QC team can check it, not just file it.
Safety Data Sheet
GHS-format SDS in English covering hazard classification, handling, storage, first-aid and spill response for the exact grade of Ortho-Xylene shipped.
Technical Data Sheet
Reference physical and chemical properties, recommended storage and typical applications, for internal circulation to your process or R&D teams.
Certificate of Origin
Confirms Indonesian origin for customs clearance and any preferential-duty claim at your destination port.
Dangerous Goods Declaration
UN packing group, classification and shipper's declaration prepared ahead of loading so documentation never holds up customs.
Third-Party Inspection
Independent pre-shipment inspection and re-sampling can be arranged on request, at your cost, for buyers who require it as a matter of policy.
Frequently asked questions
What buyers most often ask our sales desk about this grade.
01What is Ortho-Xylene used for?+
02What is the CAS number of Ortho-Xylene?+
03How is Ortho-Xylene made?+
04What purity grades does Chelora Chemicals supply?+
05Is Ortho-Xylene hazardous?+
06Why is ortho-xylene specifically used to make phthalic anhydride?+
07What packing options are available?+
08How long does delivery take?+
09Can I get a sample before placing a bulk order?+
10Do you supply other xylene isomers as well?+
Need Ortho-Xylene on spec, on time?
Send us your required purity, quantity, packing preference and destination port. Our desk quotes most enquiries within one working day.