Surely you have ever heard of dry ice. It is carbon dioxide in solid state, frozen at atmospheric pressure at a temperature of -78,5 ° C. The characteristic that makes it more special is that when it "melts" it goes directly to a gaseous state without leaving any type of moisture. Hence it is known as dry ice.
Do you want to know its properties and its different uses?
Characteristics and properties
Dry ice is obtained from gas generated as a by-product of other industrial processes. Dry ice is produced in combustion plants and fermentation reactions. As mentioned before, it's about frozen carbon dioxide. This gas at very low temperature is capable of being in a solid state. When it is sublimated it does not generate any type of liquid, water or humidity.
When this gas sublimates in a CO2-laden atmosphere, it tends to reduce the amount of humidity in the environment. This makes this gas very useful when preserving products that are sensitive to humidity, such as in the study of ice ages and in climate research in general.
Each kilogram of dry ice generates 136 frigories of energy. The gas is at a temperature of -78,5 ° C and yields about 16 extra frigories, which makes it possible to obtain a total of 152 frigories for every kilogram of dry ice.
Advantages of dry ice over water
For all other weights, dry ice is capable of cooling 170% more than conventional ice. This is particularly useful in the kitchen, as it is capable of cooling products more quickly. Since the density of dry ice is greater than 1,5 kg/dm3 and the density of water ice is 0,95 kg/dm3, it turns out that equal volume of ice used, Dry ice has a cooling capacity equivalent to 270% that of traditional ice. This is critical in places where the volume occupied by ice is essential, as dry ice is the best choice for maximizing that space. Furthermore, its use goes hand in hand with the study of climate change and its effects on glaciers, including the importance of ice in the Arctic.
Unique effect
Dry ice not only has special properties like those mentioned above, but it is also considered a bacteriostatic agent and a fungistatic agent. When sublimation occurs, an atmosphere is generated whose CO2 concentration is so high that an antimicrobial action is exerted. Therefore, it is an excellent gas to slow the growth of bacteria, molds and yeasts and create a completely sanitized environment.
This gas is capable of displacing oxygen present in the atmosphere, inside packaging, and in containers, which contributes to improving the biological quality of places where certain products need to be stored and preserved. This is especially relevant in the climate research and its influence on various ecosystems, including the oceans.
What is it used for?
Dry ice is used for various treatments and actions today. Among its uses we find:
- Medical and scientific research: To preserve organs for transplants or studies, it is highly recommended to use dry ice, since its great refrigeration capacity keeps it in good condition. It is also used in scientific research to keep biological products at low temperatures, cool exothermic reactions and ultra-fast freeze cells, tissues, bacteria and viruses.
- In restoration: In haute cuisine, dry ice is used to open up a world of possibilities to create totally exotic dishes of high quality and price. Thanks to the properties of this ice, very interesting and attractive results can be achieved for the client. The most sophisticated chefs can elaborate from original presentations to aromatic mists, cold infusions, textures and contrasts in mousses and foie gras, slushies, ice cream, foams and creams, or create striking impressive effects with smoke in mixes and elaborately prepared cocktails.
- Industry: In industry, this element is used to facilitate the assembly and adjustment of parts through cold shrinking. It is also used for cryogenic grinding and deburring of plastics and rubber, which is essential in manufacturing processes.
- Agri-food: In this sector, it is used to cool doughs in mixers during meat mincing and mixing, deep-freezing food, and temperature regulation. The use of dry ice in transportation ensures the maintenance of the cold chain, which is key in the context of the climate change.
- Large-scale distribution: It is used when urgent repairs are needed in case some refrigeration equipment is disconnected and to maintain the cold chain, including the transport of fresh food.
- Cryogenic cleaning: dry ice particles can be injected at high pressure to clean all those surfaces that have suffered some type of alteration by water, as in some electrical installations.
- Agriculture: It is used with good results for the control of pests such as rodents, moles and insects.
- Computers and electronics: It is a very good option for cooling electronic devices and improving their performance, accelerating the transmission of electrical signals, which is critical in high-demand systems.
- Construction: It is used to freeze soils and pipes to create a plug before maintenance, in processes that require rapid action.
How to make dry ice at home
If you want to see the special effects of dry ice at home, you only need the following materials:
- CO2 - carbon dioxide (we can get it from a fire extinguisher)
- A bag or cloth
- An adapter for inflating bicycle wheels
You have to place the cloth bag (it is important that it has pores so that it lets a little gas escape) around the nozzle of the extinguisher or the CO2 bottle that we are using. Once we have placed the cloth bag, we let the gas release so that it enters the bag. When the gas is released, the pressure inside it will automatically freeze it and we will have dry ice. This dry ice can be used to give an impressive effect to our desserts and drinks, since when it comes into contact with water it will sublimate and give rise to that impressive white vapor.
As you can see, dry ice is widely used in many sectors, and its effects never cease to amaze us. Now that you know the properties and uses of dry ice, try using it at home and surprise your friends.
In the preparation of dry ice at home, they mention an adapter to inflate bicycle wheels. When is this used for the preparation of dry ice?
What is dry ice called?