Gaseous nitrogen is widely used across modern industrial sectors thanks to its inert properties. It serves as a protective medium against oxidation, a refrigerant, a food additive, and is applied in the manufacturing of incandescent lamps, high-temperature metal processing, as well as for purging pipelines and sealed metal vessels.
Chemical properties of gaseous nitrogen:
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Inertness
A relatively inert, colourless and odourless gas with a density of 1.25046 kg/m³. Among simple substances, it reacts only with certain non-metals and metals (e. g. lithium under standard conditions); among compounds, with substances like acetylene and calcium carbide.
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Amphoterism
Nitrogen can exhibit amphoteric behaviour, meaning it may act as either an acid or a base in certain reactions. For example, it forms azides when reacting with alkali metals and can form salts with acids.
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Reactivity
Although chemically stable under normal conditions, nitrogen can form reactive compounds when exposed to high temperatures and pressure. Under such conditions, it reacts with oxygen to form nitrogen monoxide (NO) or nitrogen dioxide (NO₂).
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Formation of Nitrogen Compounds
Nitrogen forms a variety of compounds such as ammonia (NH₃), nitrates (NO₃⁻), nitrites (NO₂⁻), and others. These compounds are vital for biological systems and are widely used in industrial processes, including fertiliser production.
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Hazard Classification
According to Russian standard GOST 12.1.007, gaseous nitrogen is classified as a low-hazard substance when handled correctly.
Physical properties of gaseous nitrogen
- Colourless, odourless, and tasteless
- Boiling point: –195.8 °C; melting point: –210 °C
- Density at standard conditions: 1.25 g/L
- Molar mass: 28.013 g/mol
- Poorly soluble in water, though soluble in certain organic solvents
- Low viscosity and surface tension
- High diffusivity and permeability
- Non-conductive
- Low thermal conductivity
Production Methods
There are three primary methods used to extract nitrogen from atmospheric air:
Membrane Separation
Compressed, dry air is fed into a membrane module consisting of hollow polymer fibres. As the air flows through the fibres, gases diffuse at different rates. The membrane selectively removes water, argon, and oxygen, leaving high-purity nitrogen in the receiver tank.
Pressure Swing Adsorption (PSA)
Compressed air is passed through twin adsorbers working in alternating cycles. Specific pressure and temperature conditions are maintained in the system. The adsorbent captures oxygen from the air mixture, which is then released during the regeneration phase. This short, repeatable cycle yields a continuous nitrogen flow.
Cryogenic Separation
Air is compressed, filtered to remove contaminants, then passed through a moisture separator and water chiller. It is cooled and expanded, entering a rectification column. Through repeated distillation, nitrogen, argon, and oxygen are separated.
Advantages of PSA Systems
- Faster start-up and shutdown compared to cryogenic units
- High output with minimal energy consumption
- Rapid adjustment of operational parameters
- Option for remote monitoring and control
- Low maintenance requirements
- Longer adsorbent lifespan compared to membrane systems
Applications
Gaseous nitrogen is used in a wide range of industries:
- Metallurgy
- Food processing
- Medicine and pharmaceuticals
- Chemical and petrochemical industries
- Mining
- Oil and gas sector
Safety Measures
When working with gaseous nitrogen, the following precautions must be observed:
- Use of hand and eye protection to prevent contact
- Use of a hose-type gas mask
- Maintain oxygen levels in the working area at or above 19 %
- Store cylinders at 20 °C
Investment Benefits
Purchasing a nitrogen generation unit is a cost-effective investment that may pay for itself within a year. For instance, in metalworking, gas costs directly affect the pricing of final products. On-site generation helps eliminate leakage and product loss during transportation, connection, or cylinder refilling.
You can request customised equipment or receive assistance in selecting a suitable system by submitting a form on our website.
For consultation, call: +7 (495) 150-44-22.
