General conditions, carbon dioxide does not support combustion and heavier than air, carbon dioxide will cover the surface of the burning object, can make the object and the air to stop burning, so carbon dioxide can be used to extinguish the fire is commonly used fire extinguishing agent.
2, raw materials
In the chemical industry, carbon dioxide is an important raw material, used in large quantities for the production of soda ash (Na2CO3), baking soda (NaHCO3), urea [CO (NH2)2], ammonium bicarbonate (NH4HCO3), pigment lead white [Pb(OH)2-2PbCO3] and so on.
In light industry, carbon dioxide is required for the production of carbonated beverages, beer, sodas, and so on.
3, preservative
In modern warehouses are often filled with carbon dioxide, to prevent food insects and vegetables rot, to extend the preservation period. Storage of food, fruits and vegetables. Carbon dioxide storage of food due to the lack of oxygen and carbon dioxide itself inhibitory effect, can effectively prevent the growth of bacteria, mold, insects in the food, to avoid deterioration and harmful to the health of the peroxide production, and can preserve and maintain the original flavor and nutrients of food. Carbon dioxide does not cause drug residues in grains and atmospheric pollution. With carbon dioxide through the rice warehouse for 24h, can make 99% of the bugs die.
4, refrigerant
Solid carbon dioxide that is "dry ice", mainly used as a refrigerant, with the aircraft in the high altitude spraying "dry ice", you can make the air condensation of water vapor, the formation of artificial rainfall; in the laboratory, "dry ice", "dry ice", "dry ice", "dry ice", "dry ice", "dry ice", "dry ice", "dry ice", "dry ice", "dry ice", "dry ice". "Dry ice" and ether and other volatile liquids mixed, can provide -77 ℃ C about the low temperature bath. "Dry ice" can also be used as a food preservative.
Dry ice is carbon dioxide in its solid state.
Carbon dioxide is not found in large quantities in the air, but it has a large impact on life activities.
Liquid carbon dioxide is a chilling agent that can be used to preserve food and for artificial rainfall. It is also an industrial raw material that can be used to make soda ash, urea and soft drinks. Carbon dioxide can also be used to extinguish fires, because it can be directly sublimated or vaporized into a gas (not easy to wet the fire), so it is often used for precision instruments or libraries to extinguish fires, can play a very good role in extinguishing fires and no damage to equipment and books.
The gaseous carbon dioxide can be produced by cooling and pressurizing.5. In agriculture, the direct application of carbon dioxide as a fertilizer in the greenhouse, the use of carbon dioxide absorbed by the roots of plants, can enhance the photosynthesis of plants. It promotes the growth of crops and increases yields. In nature, carbon dioxide ensures the needs of green plants for photosynthesis and phytoplankton respiration in the ocean.
5. Effective stimulus for human respiration, it excites the respiratory middle keying through the stimulation of chemoreceptors outside the human body. If a person inhales pure oxygen for a long time, the body's carbon dioxide concentration is too low, can lead to respiratory arrest. Therefore, the clinical use of 5% carbon dioxide and 95% oxygen gas mixture, applied to carbon monoxide poisoning, drowning, shock, alkali poisoning treatment and anesthesia on the application. Liquid carbon dioxide cryosurgery is also more widely used.
6, as an extraction agent.
In the use of supercritical method of extracting substances, usually use the critical point of carbon dioxide as an extractant, foreign countries generally use carbon dioxide for food, beverage. Oil, spices, drugs and other processing extraction.
7, as an oilfield injection agent. Can effectively drive oil and improve oil recovery rate.
8, injected into the underground coal seams that are difficult to mine, so that the coal seams gasification, to obtain the synthetic gases and intermediates required by the chemical industry.
Carbon dioxide generally does not burn or support combustion, but magnesium can be burned in carbon dioxide, equation: 2Mg + CO2 == 2MgO + C (ignition)