Nitrogen in the air: A complete analysis of its content and industrial applications

Air is ubiquitous and essential for life. Nitrogen constitutes a significant portion of air. So, how much nitrogen is in the air? What are the industrial applications of nitrogen? Let's unveil the mysteries of nitrogen.

Nitrogen Content in Air

Air is a mixture of various gases, with nitrogen being the most abundant. Scientific measurements show that nitrogen accounts for approximately 78% of the total volume of air. Most of the air we breathe is nitrogen. The high proportion of nitrogen in the air is closely related to its stable chemical properties. A nitrogen molecule consists of two nitrogen atoms bonded by a triple covalent bond. This structure makes it difficult for nitrogen to react with other substances at normal temperature and pressure, allowing it to exist stably in the atmosphere.

Industrial Applications of Nitrogen

Chemical Industry

Nitrogen has wide-ranging applications in chemical production. Many chemical reactions require specific environments, and nitrogen provides an inert atmosphere, preventing reactants or products from reacting unnecessarily with oxygen. For example, in the synthesis of ammonia, nitrogen is a key raw material. The ammonia synthesis reaction requires high temperature, high pressure, and a catalyst to react nitrogen and hydrogen to produce ammonia. Additionally, in the production, storage, and transportation of flammable and explosive materials, nitrogen can act as a protective gas, reducing the risk of explosions. For instance, introducing nitrogen during the production of nitric acid and other chemical products can prevent the mixture from reaching its explosion limit.

Food Industry

Nitrogen also plays a vital role in the food industry. Packaging bags for common snacks like potato chips and puffed foods usually contain nitrogen. This is because nitrogen isolates oxygen, preventing food oxidation and spoilage, and extending shelf life. Simultaneously, nitrogen acts as a buffer, reducing compression and damage during transportation. In addition, in the production of beer and beverages, nitrogen can be used for back pressure during filling, preventing contact with air and maintaining the taste and quality of the beverage.

Electronics Industry

The electronics industry has extremely high environmental requirements, especially regarding the content of impurities in the air. Nitrogen is characterized by its high purity and dryness, making it widely used in the production of electronic components. For example, the manufacturing of semiconductor chips requires an ultra-clean environment, and nitrogen can be used for purging, drying, and protection, preventing contamination and oxidation of the chips. Furthermore, in the packaging of electronic devices, nitrogen can also serve as a protective gas, ensuring the quality and reliability of the packaging.

Metal Processing Industry

Nitrogen is also crucial in metal processing. Introducing nitrogen during metal heat treatment creates an inert atmosphere, preventing surface oxidation and decarburization, improving the mechanical properties and surface quality of the metal. For example, in the annealing and quenching processes of steel, nitrogen protection effectively prevents contact with oxygen, resulting in better processing results. Additionally, in metal welding, nitrogen can act as a shielding gas, preventing oxidation at the weld seam and improving welding quality.

Pharmaceutical Industry

In the pharmaceutical industry, nitrogen is primarily used in the production, storage, and transportation of pharmaceuticals. Many pharmaceuticals are highly sensitive to oxygen and humidity, prone to oxidation, hydrolysis, and other reactions that cause them to become ineffective. Introducing nitrogen creates an oxygen-free and dry environment, protecting the quality and stability of the pharmaceuticals. For example, in the production of some injections and oral solid preparations, nitrogen is used to remove air from containers, preventing contact with oxygen. Nitrogen can also be used for purging and drying in the production of pharmaceutical packaging materials, ensuring cleanliness.

As a major component of air, nitrogen not only plays a crucial role in maintaining atmospheric balance but also holds an indispensable position in industrial production. From chemicals and food to electronics, metal processing, and pharmaceuticals, nitrogen's applications are extensive, providing strong support for production and development in various fields. With continued technological advancements, the applications of nitrogen will continue to expand and deepen, bringing more convenience and benefits to life and industrial production.