Ammonia CAS 7664-41-7
Chelora Chemicals supplies anhydrous and aqueous ammonia to fertiliser, nitric acid, caprolactam, refrigeration and emissions-control users worldwide. Because anhydrous ammonia is a toxic liquefied gas, every consignment leaves with a batch-specific COA covering purity, water and oil content, the current SDS and full dangerous-goods documentation.
Also known as: Anhydrous ammonia · NH₃ · Liquid ammonia · Ammonia gas · R-717
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Price, lead time and a sample COA for Ammonia, usually within one working day. We ship worldwide.
Request a Quote Email the DeskDocumentation
- Batch-specific COA (purity, water, oil content)
- Safety Data Sheet (SDS)
- Transport and dangerous-goods documents
- Third-party inspection on request
- Certificate of origin
What is Ammonia?
Ammonia is a nitrogen-hydrogen compound, NH₃, a colourless gas at ambient with a sharp, unmistakable pungent odour. It liquefies under modest pressure, about 8.6 bar at 20 °C, and is traded as a liquefied gas.
It is the foundation of the nitrogen industry. Around 80% of global production goes into fertiliser, as urea, ammonium nitrate, ammonium phosphates and direct application, and the remainder into nitric acid, caprolactam, acrylonitrile, amines and explosives.
Ammonia is also an industrial refrigerant, designated R-717, valued for excellent thermodynamic efficiency and zero ozone depletion or global warming potential. More recently it has attracted attention as a hydrogen carrier and marine fuel.
It is acutely toxic and corrosive. Its sharp odour gives warning at concentrations far below harmful levels, which is a genuine safety advantage, but large releases are extremely dangerous.
Why Ammonia specifically
- Fixed nitrogen. The Haber-Bosch process converts atmospheric nitrogen into a reactive form that feeds global agriculture.
- A versatile reactant. Oxidises to nitric acid, reacts with CO₂ to urea, and aminates to amines, amides and nitriles.
- An efficient refrigerant. High latent heat gives better efficiency than most synthetic refrigerants with no ozone or climate impact.
- A hydrogen carrier. Liquefies at moderate pressure, which makes it far easier to ship than hydrogen itself.
How Ammonia is Manufactured
Ammonia is made by the Haber-Bosch process, combining nitrogen from air with hydrogen from a carbon feedstock or electrolysis.
- Hydrogen production. Steam reforming of natural gas is the dominant route; coal gasification and water electrolysis are the alternatives.
- Shift and purification. Carbon monoxide is shifted to CO₂, which is removed and often used to make urea on the same site.
- Nitrogen supply. Air is introduced in the secondary reformer or supplied from an air separation unit.
- Synthesis loop. Nitrogen and hydrogen react over a promoted iron catalyst at about 150 to 250 bar and 400 to 500 °C, with recycle because conversion per pass is low.
- Refrigeration and separation. Ammonia is condensed out of the loop gas by refrigeration and the unreacted gas recycled.
- Green and blue routes. Electrolytic hydrogen or carbon-captured reforming produce chemically identical ammonia with a lower carbon footprint.
Typical Commercial Specification
Figures below are representative of commercial anhydrous ammonia. Refrigeration grade and metallurgical grade carry additional limits — tell us the use and we will send the matching sheet.
| Parameter | Typical Value |
|---|---|
| Appearance | Colourless liquefied gas, pungent odour |
| Ammonia content | 99.8% min by weight |
| Water content | 0.2% max (0.5% for some agricultural grades) |
| Oil content | 5 ppm max |
| Non-volatile residue | To grade, typically 5 ppm max |
| Iron | To grade, typically 1 ppm max |
| Chlorides | To grade, typically 1 ppm max |
| Non-condensable gases | To grade, typically 100 mL/L max |
| Appearance of residue | Free of visible contamination |
| Odour | Characteristic, free of foreign odour |
Physical & Chemical Properties
| Property | Value |
|---|---|
| Chemical formula | NH₃ |
| Molecular weight | 17.03 g/mol |
| Appearance | Colourless gas; colourless liquid under pressure |
| Boiling point | −33.3 °C at 1 atm |
| Melting point | −77.7 °C |
| Vapour pressure | About 8.6 bar at 20 °C |
| Liquid density | 0.682 g/cm³ at −33 °C |
| Gas density (relative to air) | 0.59 — lighter than air |
| Flammable limits in air | About 15 to 28% by volume |
| Autoignition temperature | About 630 °C |
| Solubility in water | Extremely high — about 517 g/L at 20 °C |
| Latent heat of vaporisation | About 1370 kJ/kg — exceptional for refrigeration |
| Incompatibilities | Copper, zinc, brass and their alloys, acids, halogens, oxidisers, mercury |
Behaviour in the process
Ammonia's behaviour in a release is unusual and shapes the emergency planning around it:
- Lighter than air, but not always. Pure ammonia vapour rises, yet a cold two-phase release forms a dense aerosol that hugs the ground until it warms.
- Extremely water soluble. Water sprays absorb ammonia vapour effectively, which is the basis of mitigation. It also means moisture in the eyes and lungs concentrates it.
- Attacks copper alloys. Copper, brass and zinc are rapidly corroded; this rules out most ordinary fittings and instruments.
- Stress corrosion cracking. Very dry ammonia cracks carbon steel under stress, which is why a controlled water content is specified.
Ammonia Grades and Forms
Ammonia is bought as anhydrous liquefied gas or as an aqueous solution, and the choice is driven by volume and handling capability.
| Material | Origin / type | When it is the right choice |
|---|---|---|
| Anhydrous ammonia | 99.8%+ liquefied gas | Fertiliser, nitric acid, chemical synthesis and refrigeration |
| Aqueous ammonia | Typically 19 to 29% solution | Emissions control, water treatment and smaller-scale chemical use |
| Refrigeration-grade ammonia | Very low water and oil | Industrial refrigeration systems as R-717 |
| Urea | Solid derivative, CAS 57-13-6 | Fertiliser and SCR use where handling a toxic gas is impractical |
| Ammonium hydroxide solutions | Dilute aqueous grades | Laboratory, cleaning and specialty applications |
Stated plainly: aqueous ammonia trades toxic-gas handling for freight cost, since you are shipping mostly water. For sites without pressurised gas capability, that trade is usually worth making.
Industries We Supply Ammonia To
Ammonia reaches agriculture, heavy chemicals, refrigeration and now energy, with the specification varying more than the chemistry.
Where Ammonia is Used
Fertiliser takes roughly four fifths of global ammonia. Industrial chemicals, refrigeration and emissions control share most of the remainder.
In fertiliser manufacture
Ammonia reacts with carbon dioxide under pressure to form ammonium carbamate, which dehydrates to urea. Because the CO₂ usually comes from the same reforming unit that made the hydrogen, ammonia and urea plants are almost always built together, and that integration is what makes nitrogen fertiliser affordable.
In industrial refrigeration
Ammonia's latent heat of about 1370 kJ/kg is far higher than any synthetic refrigerant, so the mass flow needed for a given duty is small and the efficiency high. The trade-off is toxicity, which is why ammonia systems are built with machinery rooms, gas detection and strict copper-free material selection.
Need a specific grade, purity and packing format?
Tell us the grade, the grade, the water and oil limits, and your receiving pressure or refrigeration setup, the packing format you can receive and the annual quantity. We will come back with a price, a lead time, a sample COA and the full documentation set.
Quality Control & Testing
Every lot is released against a batch-specific Certificate of Analysis, with water and oil content reported alongside purity because both are critical in different applications.
- Ammonia purity — the primary grade measure.
- Water content — reported because it is a corrosion inhibitor in steel vessels and a contaminant in refrigeration systems.
- Oil content — measured in ppm because oil fouls refrigeration evaporators and catalyst beds.
- Non-volatile residue — confirming freedom from carry-over contamination.
- Iron and chlorides — reported for corrosion and catalyst reasons.
- Non-condensable gases — measured because they degrade refrigeration performance.
Common Process Problems & Likely Causes
When ammonia causes trouble, it is usually water, oil, non-condensables or material incompatibility. This table is the shortcut our technical desk works through before anyone opens a complaint file.
| Symptom | Likely cause | What to check |
|---|---|---|
| Refrigeration efficiency falling | Oil or water accumulating in the evaporator | Oil and water figures on the COA, system purge records |
| High head pressure in a refrigeration plant | Non-condensable gases in the system | Non-condensables figure and purger operation |
| Stress corrosion cracking in a steel vessel | Ammonia too dry, or oxygen contamination | Water content and vessel inspection history |
| Green deposits or rapid corrosion at fittings | Copper, brass or zinc components in contact with ammonia | Material of construction throughout the system |
| SCR catalyst activity falling | Oil or non-volatile contamination in the reagent | Oil and residue figures on the COA |
| Persistent odour around storage | Small leak at a flange, valve or relief device | Leak survey; the odour threshold is far below the harmful level |
Packaging, Storage & Shipping
- Standard packing. Cylinders, ISO tank containers, road and rail tankers for pressurised liquid; refrigerated tanks for large volumes.
- Pressure or refrigeration. Stored either under pressure at ambient or fully refrigerated at about −33 °C near atmospheric pressure, depending on scale.
- Material compatibility. Carbon steel and stainless steel only. Copper, brass, zinc and their alloys are rapidly attacked and must be excluded throughout.
- Water content as inhibitor. A controlled minimum water content prevents stress corrosion cracking in carbon steel vessels.
- Gas detection and water spray. Ammonia detection and a water spray or deluge capability are standard, since water absorbs ammonia vapour efficiently.
- Segregation. Keep apart from acids, halogens, oxidisers and mercury.
- Shelf life. Indefinite in a sealed, dedicated system. Water and oil pick-up are the practical concerns.
- Transport classification. UN 1005, ammonia anhydrous, Class 2.3 toxic gas with subsidiary 8 corrosive.
Hazards & Safe Handling
Ammonia is an acutely toxic, corrosive liquefied gas. Its sharp odour gives warning far below harmful concentrations, which is a real safety advantage, but large releases are life-threatening and demand planned emergency response.
- Acute toxicity. Toxic by inhalation. Severely irritating to eyes, skin and respiratory tract, with pulmonary oedema possible after significant exposure.
- Odour warning. Detectable at around 5 ppm, well below the exposure limit, which gives genuine early warning of a leak.
- Occupational exposure. Limits are commonly 25 ppm as an 8-hour average with a 35 ppm short-term limit; confirm the limit in your jurisdiction.
- Corrosivity. Causes severe burns to skin and permanent eye damage. The liquid also causes cold burns on contact.
- Flammability. Flammable between about 15 and 28% in air. Hard to ignite in the open but a real hazard in confined spaces.
- Water reactivity. Dissolves in water with significant heat release; use water spray on vapour, never a direct jet into liquid ammonia.
- PPE and rescue. Full face protection, chemical suit and self-contained breathing apparatus for any entry into a release area.
- Environment. Very toxic to aquatic life; prevent entry to drains and watercourses.
Regulatory & Compliance Notes
Ammonia is regulated as a toxic gas, a major-hazard substance and a fertiliser precursor. The notes below are orientation rather than legal advice.
- GHS classification. Flammable gas Category 2, gas under pressure, acute toxicity Category 3 by inhalation, skin corrosion Category 1B and acute aquatic toxicity Category 1.
- Major hazard regulation. Bulk ammonia storage falls under Seveso, COMAH, PSM and equivalent major-accident regulations in most jurisdictions.
- Dangerous goods transport. UN 1005, Class 2.3 toxic gas with subsidiary 8. ADR, IMDG, IATA and DOT rules apply to tank design, labelling and routing.
- Security and precursor controls. Ammonia and ammonium nitrate chains are subject to security and end-use reporting requirements in many countries.
- Refrigeration codes. Ammonia refrigeration systems are governed by specific design, machinery room and detection standards.
- Fertiliser regulation. Agricultural grades are subject to national fertiliser quality and registration rules.
We Supply Ammonia Worldwide
Chelora Chemicals is a supplier and export partner, not a single-plant trader. We ship Ammonia from India and from partner sources to customers across Asia, Europe, the Middle East, Africa, and North and South America, handling the export documentation, transport paperwork and freight so the material arrives ready to use.
- Incoterms. EXW, FOB, CIF, CFR and DAP quoted to suit your purchasing terms and freight arrangements.
- Ports. Regular shipments through Nhava Sheva (JNPT) and Mundra, with other ports arranged where routing and cargo rules allow.
- Documentation. Commercial invoice, packing list, certificate of origin, COA, SDS and the transport declaration issued as a complete set.
- Flexible volumes. From a single cylinder or ISO tank up to repeat bulk shipments on a supply contract.
- Supply continuity. Because we are independent of any one producer, a plant turnaround or a shipping disruption at one source does not have to become your stock-out.
Buying Ammonia from Chelora
We are an independent sourcing and supply partner. For ammonia that means settling three things at enquiry: the grade and water and oil limits, whether you receive pressurised or refrigerated product, and the toxic-gas documentation and emergency arrangements your site and regulator require.
- Documentation on every lot. Batch-specific COA (purity, water, oil content), plus SDS and the full transport paperwork.
- Analysis before commitment. Representative analysis shared ahead of a commercial order so your lab can qualify the material.
- Quantities. From a single cylinder or ISO tank through to full bulk shipments on contract supply.
- Grade matching. Agricultural, commercial or refrigeration grade, with the water, oil and non-condensable limits your system requires.
- Inspection. Independent third-party inspection available at loading when the contract requires it.
- Related products. Urea, Nitric Acid, Acrylonitrile and other feedstocks alongside Ammonia from one supplier.
How ordering works
- Send the enquiry. Product, grade or purity, quantity, destination port and the Incoterm you buy on. If you have a spec sheet, attach it — it saves a round trip.
- We quote. Price, lead time, packing format and a sample COA, normally within one working day.
- Qualify the supply. For first orders or critical applications, we share the analysis and handling documentation so your technical and safety teams can sign off before you commit.
- Confirm the order. Proforma invoice issued; payment terms agreed against the volume and the relationship.
- Allocation and QC. Material allocated and released against a batch-specific COA, with an independent inspection where the contract calls for it.
- Ship and document. Filled, labelled and loaded with the full export document set, and tracked through to arrival.
Ammonia — Common Questions
The questions our technical desk is asked most often about Ammonia. If yours isn't here, call or email and you will reach someone who knows the chemistry.
What is the CAS number of ammonia?
The CAS number for ammonia is 7664-41-7, and its EC number is 231-635-3. Its molecular formula is NH₃ with a molecular weight of 17.03 g/mol, and it is classified under HS code 2814.10.
What is ammonia used for?
About 80% goes to fertilisers — urea, ammonium nitrate and ammonium phosphates. The rest goes to nitric acid, caprolactam, acrylonitrile and amines, to industrial refrigeration as R-717, and to SCR emissions control.
Do you supply ammonia worldwide?
Yes. Chelora Chemicals supplies and exports ammonia worldwide — across Asia Pacific, Europe, the Middle East, Africa and the Americas, as well as throughout India. Every consignment carries the COA, the SDS and the toxic-gas transport documentation.
How is ammonia manufactured?
By the Haber-Bosch process: nitrogen from air reacts with hydrogen over a promoted iron catalyst at high pressure and temperature. The hydrogen comes from steam reforming natural gas, coal gasification, or water electrolysis for green ammonia.
Why does anhydrous ammonia contain a small amount of water?
Because completely dry ammonia causes stress corrosion cracking in carbon steel vessels. Agricultural and commercial grades specify a minimum water content, typically around 0.2%, which acts as a corrosion inhibitor.
Why must copper be excluded from ammonia systems?
Ammonia attacks copper, brass, zinc and their alloys rapidly, forming complexes and corroding fittings. Carbon steel and stainless steel are the only standard materials of construction.
Is ammonia hazardous?
Yes. It is an acutely toxic gas, corrosive to skin and eyes, and flammable at high concentration. Its strong odour is detectable far below harmful levels, which gives useful warning, but large releases are life-threatening.
What are the UN number and transport class?
UN 1005, ammonia anhydrous, Class 2.3 toxic gas with subsidiary risk 8 corrosive. ADR, IMDG, IATA and DOT rules apply to tank design, labelling and routing.
How should ammonia be stored?
Either pressurised at ambient temperature or fully refrigerated at about −33 °C near atmospheric pressure, in copper-free carbon or stainless steel systems with gas detection and water spray capability.
Should I buy anhydrous or aqueous ammonia?
Anhydrous makes sense at volume and where you have pressurised gas handling. Aqueous ammonia at 19 to 29% is far simpler to handle and is the usual choice for emissions control and water treatment, at the cost of shipping mostly water.
Why is ammonia used as a refrigerant?
Its latent heat of vaporisation is about 1370 kJ/kg, far above synthetic refrigerants, which makes ammonia systems highly efficient. It also has zero ozone depletion and zero global warming potential.
What packing sizes and order quantities are available?
Cylinders, ISO tank containers, road and rail tankers, and refrigerated bulk shipments. Orders run from a single cylinder up to repeat bulk cargoes on contract supply.
Ready to source Ammonia?
Send us your specification, grade and annual volume. You will get a price, a realistic lead time and a sample COA from someone who understands what the material has to do in your process — delivered anywhere in the world.