Production of dry ice at home

Dry ice is a solid carbon dioxide (dioxide) that rapidly converts to steam under atmospheric pressure and room temperature. The liquid phase is avoided.

Externally, carbon dioxide really resemblesordinary ice (hence the name). The temperature of "dry ice" is close to -79 ° C. "Melts", absorbing 590 kJ / kg. Non-toxic. It is used, first of all, for cooling quickly deteriorating products during transportation or in the absence of refrigerating chambers.

Dry ice is in demand in engineering, foundryproduction of rubber products, plastic and polymer processing, water / railway transport, laboratories and other industries (facade restoration, cleaning of wooden surfaces, cleaning of ventilation systems).

For industrial production of carbon dioxidecarbon dioxide plants are required. Get dry ice (the price of a kilogram varies from 35 to 45 rubles, depending on the region and the complexity of delivery) is not always obtained. First of all, such factors as the distance from the place of production of carbon dioxide and the complexity of transportation play a role here (special (thermal) containers are needed). But if these problems are still solved, then what to do with urgency? After all, there are situations when solid carbon dioxide is needed immediately, and its search and delivery can go not only hours, but also a day.

It turns out that even in a desperate situation, it would seem, you can get the time to work for you, in a few minutes, preparing solid carbon dioxide at home.

Want to know how to make dry ice? Everything new, as is known, is forgotten old. One has only to remember the school curriculum.

For the independent production of a small amount of dry ice you will need:

- Fire extinguisher (carbon dioxide, labeled type OU, the other is not suitable);

- a sack sewn from a cotton thick fabric;

- mittens (felt or cotton, but very dense);

- mask to protect the face (or at least glasses).

Carbon dioxide fire extinguisher (OU labeling) alreadyis filled with carbon dioxide, which is in a liquid state (under pressure) and reaches a rather low temperature (approximately -72 ° C) at the output. That's why precautionary measures are so important (gloves, mask).

We proceed. Take the fire extinguisher, remove the seal from it and pull out a safety pin from the handle. Prepared in advance, we put the bag on the bell, place the ballon on the floor (sideways) and gently, slowly, press the lever. By intermittent frequent pressing, we gradually release carbon dioxide. Prior to this, it is important to fix the bag on the bell (it is enough to press it with your hand), otherwise it will fly off (under pressure) from the first push.

When the bag is full, release the lever and turn the contents inside out - you will see pieces of the very dry ice that we need so much.

Long storage of the product is possibleOnly at a temperature of -80 ° C and lower. At home, such conditions are almost impossible to create, but you can extend the life of dry ice by creating a kind of thermos. It is perfectly suitable for a cardboard box, laid out inside with polyethylene and foam. Air circulation must be avoided.