Ammonia
Anhydrous ammonia, the fixed-nitrogen platform. A liquefied toxic gas that starts the fertiliser chain and increasingly the low-carbon fuel one.
Molecular Structure
What is Ammonia?
Ammonia is a nitrogen atom bonded to three hydrogens, with a lone pair occupying the fourth position. That lone pair makes the molecule pyramidal rather than flat, gives it a dipole, and makes it a base and a ligand.
It also makes ammonia hydrogen-bond, which is why a molecule of only 17 g/mol is a liquid below −33 °C rather than a permanent gas. Handling follows from that: ammonia is shipped either refrigerated at −33 °C and atmospheric pressure, or pressurised at ambient temperature at around 8.6 bar.
Essentially all of it is made by the Haber-Bosch reaction of nitrogen with hydrogen over a promoted iron catalyst at high pressure. Roughly half of world ammonia goes straight to urea, and the fertiliser chain as a whole takes the large majority — though ammonia is now also being developed as a hydrogen carrier and marine fuel.
Chelora supplies commercial anhydrous ammonia at ≥99.5 wt%, with water content held in the range that protects carbon steel vessels against stress corrosion cracking, and oil content controlled. Refrigerated and pressurised logistics arranged to suit your receiving facility.
Quick Reference
Key Physical & Chemical Properties
Structure & Bonding
One lone pair explains most of ammonia's behaviour: the pyramidal shape, the basicity, the hydrogen bonding that keeps it liquid, and its ability to coordinate to metals. It is also what makes ammonia react so readily with acids to give the fertiliser salts.
Structure — pyramidal nitrogen with lone pair
Structural Identity
- IUPAC NameAzane (ammonia)
- Molecular FormulaNH₃ (Hill notation H₃N)
- Molecular Weight17.03 g/mol
- Hybridisationsp³ nitrogen, one lone pair
- GeometryTrigonal pyramidal
- N–H bond length1.012 Å
- H–N–H bond angle107.8°
- Dipole moment1.47 D
- Vapour density0.60 — lighter than air
- CAS Number7664-41-7
- InChI KeyQGZKDVFQNNGYKY-UHFFFAOYSA-N
Product Specifications
Chelora supplies Ammonia in standard and custom grades. Contact us for specification sheets tailored to your process.
| Chemical name | Ammonia, anhydrous |
|---|---|
| CAS Number | 7664-41-7 |
| Molecular formula | NH₃ |
| Molecular weight | 17.03 g/mol |
| Purity (commercial grade) | ≥ 99.50 wt% |
| Purity (metallurgical grade) | ≥ 99.995 wt% |
| Water content | 0.20 – 0.50 wt% |
| Oil content (max) | ≤ 5 ppm wt |
| Non-condensable gases (max) | ≤ 0.10 vol% |
| Residue on evaporation (max) | ≤ 25 ppm wt |
| Appearance | Clear, colourless liquefied gas |
| Boiling point | −33.3 °C at 1 atm |
| Vapour pressure | ≈ 8.6 bar at 20 °C |
| Liquid density | 0.682 g/cm³ at −33 °C |
| Flammable limits | 15 – 28% v/v in air |
| Autoignition temperature | 651 °C |
| UN Number | UN 1005 (Ammonia, anhydrous) |
| IMDG / ADR Class | Class 2.3 (Toxic Gas), subsidiary risk 8 |
Downstream Applications & Derivatives
Key derivative chains and industrial uses of Ammonia.
Urea & Nitrogen Fertiliser
Reaction with carbon dioxide gives urea, the largest single ammonia outlet. Direct application and ammonium salts take much of the remainder of the fertiliser demand.
Nitric Acid & Nitrates
Catalytic oxidation over platinum-rhodium gauze gives nitric acid, and from there ammonium nitrate and calcium ammonium nitrate for agriculture and industrial use.
Ammonium Phosphates & Sulphate
Neutralisation with phosphoric acid gives DAP and MAP; with sulfuric acid, ammonium sulphate — the compound fertiliser building blocks.
Caprolactam & Acrylonitrile
Ammonia supplies the nitrogen in caprolactam for nylon 6, in acrylonitrile via propylene ammoxidation, and in melamine made from urea.
Industrial Refrigeration
As refrigerant R-717, ammonia has excellent thermodynamic efficiency and zero ozone depletion or global warming potential — standard in cold stores and food processing.
Emissions Control & Fuel
Used in selective catalytic reduction to abate NOx from power and marine engines, and under active development as a carbon-free marine fuel and hydrogen carrier.
Why source Ammonia through Chelora Petrochem?
Verified Origin
Full origin certification and asset-backed supply chain documentation — no grey-market supply.
Grade Flexibility
Commercial and metallurgical grades available. Water and oil content can be specified to match your storage metallurgy and downstream catalyst requirements.
Full Documentation
CoA, SDS, UN transport docs, REACH compliance, and destination-market certificates with every shipment.
Logistics Support
Experienced in liquefied toxic gas logistics — refrigerated and pressurised movements, receiving-facility compatibility checks, and full UN 1005 Class 2.3 documentation for Indian and international delivery.
Storage & Handling Guidelines
Always refer to the full SDS before handling. The following is a summary of key requirements.
- Maintain the specified minimum water content in carbon steel storage — dry ammonia promotes stress corrosion cracking in stressed carbon steel vessels and this is a well-documented failure mode.
- Never rely on smell to judge safety. Ammonia is detectable by odour far below harmful levels, but olfactory fatigue sets in quickly and people stop noticing it.
- Fit fixed ammonia detection with alarms in storage, pump and loading areas, and confirm detector calibration on a defined schedule.
- Provide safety showers and eyewash within immediate reach of all transfer points — ammonia causes severe, rapid eye and skin injury including cold burns from liquid contact.
- Keep full-face escape respirators or SCBA available and make sure operators are trained and fit-tested to use them.
- Use only materials rated for ammonia service; copper, brass, zinc and their alloys are attacked and must not appear anywhere in the system.
- Water-spray or fog can knock down a vapour cloud, but never apply water directly into a liquid ammonia spill — it reacts vigorously and increases vapour generation.
- Keep away from acids, halogens, hypochlorites and mercury; the reaction of ammonia with chlorine-based products is violent and generates toxic gases.
Hazard Summary
Classification: Flam. Gas 2 (H221) · Press. Gas, liquefied (H280) · Acute Tox. 3 inhalation (H331) · Skin Corr. 1B (H314) · Eye Dam. 1 (H318) · Aquatic Acute 1 (H400).
Acute toxicity: Ammonia is corrosive to the respiratory tract. Moderate concentrations cause immediate eye and airway irritation; high concentrations cause laryngeal swelling and pulmonary oedema, which can be delayed by hours after apparent recovery. Anyone with significant exposure needs medical observation even if they seem well.
Cold burns: Liquid ammonia is at −33 °C at atmospheric pressure and causes severe frostbite on contact, on top of its chemical corrosivity.
Exposure limits: ACGIH TLV 25 ppm 8-hour TWA with a 35 ppm STEL; EU IOELV 20 ppm TWA / 50 ppm STEL; OSHA PEL 50 ppm. The NIOSH IDLH is 300 ppm. Confirm the limit in force in your jurisdiction.
Flammability: Ammonia's 15–28% flammable range is narrow and it is hard to ignite in open air, which leads people to underestimate it. In a confined space with an ignition source it will burn, and the vapour is lighter than air so it accumulates at high level.
Environment: Very toxic to aquatic life. Bunding, vapour containment and spill response planning are required, and releases are reportable in most jurisdictions.
PPE minimum: Chemical goggles and face shield, ammonia-rated gloves and chemical suit for transfer work, and self-contained breathing apparatus available for emergency response.
Consult the full SDS for exposure limits, spill containment, emergency response, and disposal before any use.
Frequently Asked Questions
Technical and commercial questions about Ammonia sourcing and specifications.
What is ammonia used for?
The fertiliser chain takes the large majority. Roughly half of world ammonia is converted to urea, with the rest going to nitric acid and ammonium nitrate, DAP and MAP, and ammonium sulphate. Industrial outlets include caprolactam for nylon 6, acrylonitrile, melamine, refrigeration as R-717, and NOx abatement by selective catalytic reduction. Ammonia as a marine fuel and hydrogen carrier is an emerging demand centre.
How is ammonia produced?
By the Haber-Bosch process: nitrogen from air is reacted with hydrogen over a promoted iron catalyst at roughly 150–300 bar and 400–500 °C. The hydrogen usually comes from steam reforming of natural gas, or from coal gasification. Low-carbon variants — blue ammonia with carbon capture, and green ammonia from electrolytic hydrogen — use the same synthesis loop with a different hydrogen source.
Why does anhydrous ammonia specification include a minimum water content?
Because completely dry ammonia causes stress corrosion cracking in stressed carbon steel vessels and piping. A small amount of water, typically 0.2% or more, inhibits the mechanism. It is one of the few specifications where a contaminant is deliberately kept in rather than driven out, and it is the reason ammonia intended for carbon steel storage is not supplied bone dry. Confirm the requirement against your own storage metallurgy.
Is ammonia flammable or toxic?
Both, but the toxic hazard dominates in practice. It is classified as a Class 2.3 toxic gas with a subsidiary corrosive risk. Its flammable range of 15–28% is narrow and it is difficult to ignite in open air, which is exactly why people underestimate the fire risk in confined spaces. The acute hazard that hurts people is inhalation and eye contact — ammonia is corrosive to the respiratory tract and can cause delayed pulmonary oedema.
Can you rely on the smell of ammonia as a warning?
No, and this is a common and dangerous assumption. Ammonia is detectable by odour at a few parts per million, well below harmful concentrations, which sounds reassuring. But olfactory fatigue sets in rapidly, so someone working in an ammonia atmosphere stops perceiving it while the concentration may still be rising. Fixed gas detection with alarms is the control that actually works.
What documentation does Chelora provide?
Every shipment includes a Certificate of Analysis covering purity, water content, oil content, non-condensable gases and residue on evaporation; a Safety Data Sheet (GHS/REACH); UN 1005 Class 2.3 with subsidiary risk 8 transport documentation; receiving-facility compatibility confirmation; an origin certificate; and any destination-market certificates required.
Request a quote or specification sheet
Talk to Chelora's sourcing team about Ammonia grade, volume, logistics, documentation, and lead times. We respond within one business day.
