Dry ice is a very necessary and irreplaceable thing. It can be used to maintain a constant low temperature, to cool any household items in high ambient temperatures. It is widely used in industry, as a cooler for tanks and refrigerators, in cooking when creating culinary masterpieces. But it is not always possible to acquire dry ice when it is so needed.
There are several options for how to make or make dry ice with your own hands in an ordinary kitchen.
What is dry ice?
In fact, this substance has nothing to do with frozen water, that is, with ordinary ice, except for the ability to maintain low temperatures or cool something. The dry ice formula is the same as for carbon dioxide - CO2. In fact, it is a gas that is converted to a solid state of aggregation, bypassing the liquid phase.
With this chemical compound we meet every day. It is contained in exhaled air. When you buy carbonated water or a drink in a store, you have seen how, when you open a bottle, carbon dioxide bubbles rush out.
A large amount of it is emitted with transport exhaust gases and is contained in the ambient air. Because of the ability to inhibit combustion processes, it is used in the manufacture of fire extinguishers for domestic and industrial use. Carbon dioxide is used by plants to carry out the process of photosynthesis. But its isolation from the environment is a very laborious and costly process.
Getting dry ice
No matter how absurd it may sound, dry ice is gas. On an industrial scale, it is obtained by cooling carbon dioxide at high pressure. At home, these processes will not work, because specialized equipment and the creation of certain conditions are necessary. Nevertheless, some options for how to get dry ice with your own hands do exist.
Fire extinguisher dry ice
Initially, to get dry ice you will need a fire extinguisher, a pouch of dense fabric and wire or duct tape.
Attach the existing bag to the base of the bell of the fire extinguisher so that there are no holes left. To be sure, it is better to seal it with tape or insulating tape. Tightness plays a very important role here. Next, you should carefully remove the fuse from the handle of the fire extinguisher and release a few jets of carbon dioxide by pressing the drain valve. Thus, carbon dioxide, which is in the cylinder of a fire extinguisher under pressure, does not have time to cool down and accumulates in the bag in the form of powder or crystals. In order for it not to evaporate, it must be placed in an airtight container or bag and tightly closed.
In the same way, you can get dry ice with your own hands from a carbon dioxide cylinder, which is used for welding. The cylinder valve should be opened very slowly, since the gas pressure in it is very high. It should be extremely careful to prevent carbon dioxide from getting on the skin of the hands and face, as this can cause frostbite.
Dry ice from a test tube
The following method may come in handy if you have access to the simplest laboratory equipment. If this is not possible, then at home it can be used without any problems. To do this, you need a fire extinguisher, safety glasses, baking soda, vinegar and a durable plastic bag.
Do-it-yourself dry ice can be obtained in small quantities with the help of a few simple laboratory experiments.
To do this, you need to get carbon dioxide by mixing soda, which is available in any kitchen, and table vinegar. The structure and formula of dry ice determine its gaseous state. For the convenience of collecting carbon dioxide, this experiment should be carried out in a glass test tube with a
vent tube. The end of the tube should be placed in water. Rising bubbles of carbon dioxide will fill another tube, displacing water. To get more carbon dioxide, they should fill in the existing plastic bag.
In order to get dry ice, the temperature of which is very low, you will need carbon dioxide and the creation of certain conditions. This is not possible in a simple laboratory or at home. The gas from the bag can be used as a base or substrate to increase the amount of dry ice. But it needs to be drastically cooled. To do this, the gas bag must be fixed on the same source of dry ice, a fire extinguisher or a cylinder, and release several jets into the bag. Thus, dry ice will cool carbon dioxide from the packet, which will contribute to its precipitation in the solid phase.
Dry ice use
The temperature of dry ice is so low that it will be enough to make homemade ice cream or other desserts that require cooling or quick freezing. It can also be used to cool foods and drinks at an outdoor picnic, but contact with moisture should be avoided.
Dry ice in water begins to turn into a gaseous state, which is accompanied by copious heavy heavy smoke.
Safety precautions
Before using a fire extinguisher for your experiments, you should make sure that it is carbon dioxide. On its case there should be a special information marking. The use of other types of fire extinguishers will not allow you to get the expected result and can be dangerous.
Do not try to get dry ice from cylinders for a gas or air gun. Opening these objects is extremely dangerous and can lead to unpredictable consequences. When working with a fire extinguisher, it is necessary to use safety glasses and gloves to avoid getting cold carbon dioxide on the mucous membranes.
A carbon dioxide fire extinguisher is best purchased at the appropriate store. Then you can be sure that it is fully operational. Dry ice can be obtained from it, periodically refueling it, for example, in the fire department.