[Chemical Knowledge]：The nature, use, upstream and downstream raw materials, storage methods of sulfur dioxide, introduction of sulfur dioxide

Sulfur dioxide properties

Sulfur dioxide (SO₂) is a colorless, strongly irritating gas with a high water solubility. Chemically, sulfur dioxide is a medium-strength acidic oxide that can be dissolved in water into sulfurous acid (H₂ SO). In the air, sulfur dioxide can be further oxidized to form sulfur trioxide (SO) and finally sulfuric acid (H₂ SO). Sulfur dioxide has a boiling point of -10°C and a melting point of -72°C. It exists in the form of gas at room temperature and is easy to liquefy.

Sulfur dioxide uses

Sulfur dioxide is widely used in industry. It is an important raw material for the production of sulfuric acid, which is the most widely used basic chemical product in the chemical industry. Sulfur dioxide is used as a bleaching agent in the paper industry, especially in the pulp bleaching process, to remove impurities from the pulp by reduction. Sulfur dioxide is also used as a food preservative and antioxidant, commonly used in the preservation of dried fruits and vegetables. Its preservative properties are mainly achieved by inhibiting the growth of microorganisms. Sulfur dioxide plays an indispensable role in many fields such as pharmaceuticals, dyes, and detergents.

Sulfur dioxide upstream and downstream raw materials

The main upstream raw materials of sulfur dioxide are sulfur and pyrite. Sulphur is mainly derived from by-products of the petroleum refining process, and can also be obtained from natural sulfur mining. Pyrite, on the other hand, produces sulfur dioxide through the roasting process of the ore, which reacts as FeS₂ reacts with oxygen at high temperatures to produce Fe₂ O₂ and SO₂. In terms of downstream products, the main products of sulfur dioxide include sulfuric acid, sulfite and other sulfur-containing compounds. Sulfuric acid is the most important downstream product, widely used in chemical, chemical, metallurgical and other industries. Sulfur dioxide is also used to produce various sulfites, such as sodium sulfite, calcium sulfite, etc. These compounds also have important applications in papermaking, sugar making and other industries.

Sulfur dioxide storage method

Because sulfur dioxide is highly toxic and corrosive, its storage requires special attention to safety. Generally, sulfur dioxide is stored in liquid form in a pressure tank. The pressure tank should have a good seal and be equipped with a corrosion-resistant lining. The storage environment should be kept dry and ventilated, avoiding direct sunlight and high temperature. The storage area needs to be equipped with perfect leakage detection and emergency treatment devices to prevent leakage accidents. In the process of transportation, special steel cylinders or tankers should be used. The transportation vehicles must meet relevant safety standards and be equipped with necessary safety protection measures.

Environment and Safety

Sulfur dioxide is one of the main air pollutants, and its emission has a significant impact on the environment and human health. Sulfur dioxide combines with water vapor to form acid rain, causing damage to soil, water and buildings. The inhalation of sulfur dioxide will stimulate the respiratory system, causing asthma, bronchitis and other diseases. In order to reduce sulfur dioxide emissions, the industry has adopted a variety of treatment measures, including desulfurization technology and emission control. The commonly used desulfurization methods include wet desulfurization, dry desulfurization and adsorption, among which wet desulfurization is the most common and effective.

Future Outlook

With the increasingly stringent environmental regulations and the improvement of public awareness of environmental protection, the emission control of sulfur dioxide will be paid more and more attention. In the future, the development of clean production technology and green chemical technology will help reduce sulfur dioxide emissions. For example, the combustion of sulfur to produce sulfur dioxide can reduce emissions through efficient exhaust gas treatment systems and process optimization. The development of new catalysts and adsorption materials to improve the conversion and utilization of sulfur dioxide will also be an important research direction in the future.

Conclusion

As an important chemical raw material, sulfur dioxide is widely used in industrial production. Strict safety management and environmental protection measures are required during its production, storage and use. In the future, with the advancement of technology and the improvement of environmental protection requirements, the production and use of sulfur dioxide will be more efficient and cleaner. This not only contributes to the sustainable development of the chemical industry, but also has important implications for environmental protection and public health.