Propylene
The second-largest volume olefin feedstock. A colourless, flammable gas that anchors polypropylene, propylene oxide, acrylics, cumene, and the broader oxo-chemical chain.
Molecular Structure
What is Propylene?
Propylene (propene) is a three-carbon alkene with one C=C double bond. It is the world's second-highest-volume petrochemical, produced mainly as a co-product of steam cracking and fluid catalytic cracking (FCC).
Propylene's double bond sits between C-1 and C-2, making C-1 a terminal alkene well-suited to coordination–insertion polymerisation. The methyl group at C-3 introduces steric asymmetry that Ziegler–Natta and metallocene catalysts exploit to produce isotactic, syndiotactic, or atactic polypropylene with tailored properties.
Chelora sources polymer-grade (≥99.5%) and chemical-grade (≥99.0%) propylene from verified cracker and refinery assets, with full CoA, SDS, and logistics support.
Quick Reference
Key Physical & Chemical Properties
Structure & Bonding
Propylene's reactivity is defined by its C=C (double) — the site of polymerisation and other industrially important reactions.
Lewis structure — sp²
Structural Identity
- IUPAC NamePropene
- Molecular FormulaC₃H₆
- Molecular Weight42.08 g/mol
- Hybridisationsp²
- Bond typeC=C (double)
- C=C bond length1.34 Å
- GeometryPlanar at C=C
- CAS Number115-07-1
- InChI KeyQQONPFPTGQHPMA-UHFFFAOYSA-N
Product Specifications
Chelora supplies Propylene in standard and custom grades. Contact us for specification sheets tailored to your process.
| Chemical name | Propylene |
|---|---|
| CAS Number | 115-07-1 |
| Molecular formula | C₃H₆ |
| Molecular weight | 42.08 g/mol |
| Purity (standard grade) | ≥ 99.5 mol% |
| Purity (commercial grade) | ≥ 99.0 mol% |
| Physical state (ambient) | Gas (ambient) |
| Boiling point | −47.6 °C at 1 atm |
| Melting point | −185.2 °C |
| Flammable limits | 2.0 – 11.1% v/v v/v in air |
| Propane (max, PG) | ≤ 500 ppm vol |
| Propadiene + Methylacetylene (max) | ≤ 10 ppm vol |
| Moisture (max) | ≤ 10 ppm wt |
| Oxygen (max) | ≤ 5 ppm vol |
| Critical temperature | 91.8 °C |
| Critical pressure | 46.0 bar |
| UN Number | UN 1077 |
| IMO / IMDG Class | Class 2.1 (Flammable Gas) |
Downstream Applications & Derivatives
Key derivative chains and industrial uses of Propylene.
Polypropylene (PP)
The dominant use. Propylene is polymerised to isotactic PP for fibres, films, moulded parts, and automotive components — the world's second-largest thermoplastic by volume.
Propylene Oxide & Polyols
Epoxidation of propylene gives propylene oxide (PO), which is ring-opened to polyether polyols for polyurethane foams, and to propylene glycol for resins and de-icers.
Acrylonitrile (ACN)
Ammoxidation of propylene over bismuth-molybdate catalyst gives acrylonitrile — feedstock for ABS, SAN, acrylic fibres, and adiponitrile for nylon-6,6.
Cumene & Phenol Chain
Alkylation of benzene with propylene gives cumene, which is oxidised and cleaved to phenol and acetone — the gateway to BPA, epoxy resins, and polycarbonate.
Oxo-Chemicals
Hydroformylation (oxo process) converts propylene to n-butyraldehyde and isobutyraldehyde, which are reduced or oxidised to alcohols, acids, and plasticiser intermediates.
Acrylic Acid & Esters
Two-stage oxidation of propylene gives acrylic acid, esterified to acrylates used in superabsorbent polymers, coatings, adhesives, and personal care formulations.
Why source Propylene through Chelora Petrochem?
Verified Origin
Full origin certification and asset-backed supply chain documentation — no grey-market supply.
Grade Flexibility
Standard and custom grades available. Impurity specifications can be tailored to your process and catalyst system.
Full Documentation
CoA, SDS, UN transport docs, REACH compliance, and destination-market certificates with every shipment.
Logistics Support
Experienced in specialised chemical logistics for compressed gases and volatile liquids — 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 well-ventilated, dedicated area away from ignition sources, heat, and sunlight.
- All electrical equipment in storage and handling areas must be ATEX/IECEx rated for the applicable zone.
- Ensure full bonding and earthing of all transfer equipment during any transfer operation.
- Never store with strong oxidisers, halogens, or materials that generate static.
- Install continuous gas detection with audible and visual alarms set below the LEL.
- Use only approved pressure-rated piping, valves, and fittings with compatible materials.
- Conduct pre-use and post-use leak checks with suitable gas detection equipment.
- Maintain inhibitor levels where applicable; check on receipt and periodically during storage.
Hazard Summary
Classification: Flammable Gas/Liquid · Flammable limits 2.0 – 11.1% v/v v/v · UN 1077.
Flammability: Highly flammable — never rely on odour to detect leaks. Use continuous gas monitoring below LEL.
Health: Asphyxiant in enclosed spaces. Oxygen monitoring mandatory in confined areas. Follow occupational exposure limits (OELs) per SDS.
PPE minimum: Chemical goggles, appropriate gloves, flame-retardant clothing, and supplied-air respirator where oxygen deficiency is possible.
Consult the full SDS for exposure limits, spill containment, emergency response, and disposal before any use.
Frequently Asked Questions
Technical and commercial questions about Propylene sourcing and specifications.
What is propylene used for?
Propylene is the feedstock for polypropylene (the world's second-largest thermoplastic), propylene oxide and polyols, acrylonitrile, cumene/phenol, acrylic acid, and a broad range of oxo-chemicals via hydroformylation.
What is the difference between polymer grade and chemical grade propylene?
Polymer grade (≥99.5%) meets the impurity specifications for Ziegler–Natta and metallocene PP catalysts — particularly for propadiene, methylacetylene (MAPD), and moisture. Chemical grade (≥99.0%) is suitable for PO synthesis, oxo process, and other routes with less critical catalyst systems.
How is propylene produced?
The two primary routes are steam cracking of naphtha or LPG (co-product alongside ethylene) and fluid catalytic cracking (FCC) of vacuum gas oil in refinery operations. On-purpose routes include propane dehydrogenation (PDH) and metathesis. PDH capacity has grown rapidly, particularly in China and the US.
Is propylene flammable?
Yes — propylene is a highly flammable gas with a flammability range of 2.0–11.1% v/v in air. It must be stored in pressurised vessels away from ignition sources with continuous gas detection and full ATEX-rated electrical equipment.
What CAS number and formula does propylene have?
Propylene has CAS number 115-07-1, molecular formula C₃H₆, and molecular weight 42.08 g/mol. Its IUPAC name is propene. The molecule has a C=C double bond between C-1 and C-2 with a methyl group at C-3.
What documentation does Chelora provide?
Every shipment includes a Certificate of Analysis (CoA), Safety Data Sheet (SDS/MSDS to GHS standards), UN transport documentation, and any destination-market regulatory certificates required.
Request a quote or specification sheet
Talk to Chelora's sourcing team about Propylene grade, volume, logistics, documentation, and lead times. We respond within one business day.
