How to make Dry Ice ?

Question

I wounder how you make dry ice at home ?

Answer 1

Can't do it at home, household refrigeration equipment is unable to go to that low of a temperature.

Answer 2

1

Answer 3

No, an Ice Pack does not contain dry ice. Dry ice a frozen carbon dioxide (the stuff you breath out). If an ice pack had dry ice in it, when it heated it would burst. This is because solid carbon dioxide coverts to gas carbon dioxide when it heats up. The gas form takes up a much greater volume then the solid form.

Answer 4

The best home method is to obtain a carbon dioxide cylinder, and obtain the solid by folding a piece of closely woven dark cloth over the nozzle in the shape of a sealed bag. Hold this bag tightly round the nozzle of the cylinder and open the valve at full blast for 5 to 10 seconds. The gas cools on expansion and solidifies, forming dry ice as loose 'snow'. It sublimes at –78°C becoming an extremely cold gas so watch out.

Answer 5

This page shows the phase diagrams for water and carbon dioxide. What you can see is that, at normal pressures, carbon dioxide moves straight between gas and solid. It is only at much higher pressures that you find liquid carbon dioxide. For example, a high-pressure tank of carbon dioxide or a carbon-dioxide fire extinguisher contains liquid carbon dioxide.

To make dry ice, you start with a high-pressure container full of liquid carbon dioxide. When you release the liquid carbon dioxide from the tank, the expansion of the liquid and the high-speed evaporation of carbon dioxide gas cools the remainder of the liquid down to the freezing point, where it turns directly into a solid. If you have ever seen a carbon-dioxide fire extinguisher in action, you have seen this carbon-dioxide snow form in the nozzle. You compress the carbon-dioxide snow to create a block of dry ice.

Dry Ice Safety
If you ever have a chance to handle dry ice, you want to be sure to wear heavy gloves. The super-cold surface temperature can easily damage your skin if you touch it directly. For the same reason, you never want to taste or swallow dry ice, either.
Another important concern with dry ice is ventilation. You want to make sure the area is well-ventilated. Carbon dioxide is heavier than air, and it can concentrate in low areas or enclosed spaces (like a car or a room where dry ice is sublimating). Normal air is 78% nitrogen, 21% oxygen and only 0.035% carbon dioxide. If the concentration of carbon dioxide in the air rises above 5%, carbon dioxide can become toxic. Be sure to ventilate any area that contains dry ice, and do not transport it in a closed vehicle.

Answer 6

HOW DRY ICE IS MADE
The first step in making dry ice is to compress carbon dioxide gas until it liquefies, at the same time removing the excess heat. The C02 gas will liquefy at a pressure of approximately 870 pounds per square inch at room temperature. Next, the pressure is reduced over the liquid carbon dioxide by sending it through an expansion valve into an empty chamber. The liquid will flash, with some turning into gas causing the remainder to cool. As the temperature drops to -109.3°F, the temperature of frozen CO2, some of it will freeze into snow. This dry ice snow is then compressed together under a large press to form blocks or extruded into various sized pellets. Dry Ice is much heavier than traditional ice, weighing about double.

DRY ICE MAKERS
Dry Ice machines are available in all sizes and use liquid CO2. Hand held ones make soft Dry Ice that dissipates quicker. Large commercial machines use hydraulic presses to compress the Dry Ice snow with up to 60 Tons of pressure. It can produce a 55 pound block in under 60 seconds.

Answer 7

Making dry ice

Safety :- Wear eye protection and gauntlet-style leather gloves when making or handling solid carbon dioxide.

Obtaining dry ice :-
There are two main methods of getting a source of dry ice.

1.Using a cylinder of carbon dioxide :-

To obtain some solid carbon dioxide from the cylinder, fold a piece of closely woven cloth (preferably of dark colour) in the form of a bag. Hold this bag tightly round the nozzle of the cylinder and open the valve at full blast for 5 to 10 seconds. The gas cools on expansion and solidifies, forming dry ice as loose 'snow'.

Where the cylinder is of the siphon type it should be kept upright. If it is an ordinary cylinder it should be held upside-down during this process.

It is possible to make the solid 'snow' by expansion before the lesson begins and to store it in a wide-necked Thermos flask.

Remember that the first production of solid carbon dioxide from the cylinder may not produce very much, because the cylinder and its attachments have to cool down.

type of cylinder:-

A CO2 gas cylinder should be fitted with a dip tube (this is also called a ‘siphon type’ cylinder). This enables you to extract from the cylinder bottom so that you get CO2 in its liquid form, not the vapour.

NOTE: A plain black finish to the cylinder indicates that it will supply vapour from above the liquid. A cylinder with two white stripes, diametrically opposite, indicates it has a siphon tube and is suitable for making dry ice.

A cylinder from British Oxygen will cost about £80 per year for cylinder hire and about £40 each time you need to get it filled up. (The refill charge can be reduced by having your chemistry department cylinders filled up at the same time.)

Don't be tempted to get a small cylinder - it will run out too quickly.

If the school has its own CO2 cylinder there will be no hire charge, but you will need to have it checked from time to time (along with fire extinguisher checks). Your local fire station or their suppliers may prove a good source for refills.

A dry ice attachment for the cylinder

Dry ice disks can be made using an attachment that fits directly on to a carbon dioxide cylinder with a siphon tube. Section 13.3.1 of the CLEAPSS Laboratory Handbook explains the use of this attachment (sometimes called Snowpacks or Jetfreezers). This form is most useful for continuous cloud chambers and low-friction pucks.

You can buy a Snowpack dry ice maker from Scientific and Chemical. Type ‘dry ice’ into their cat no/description box. The product number is GFT070010

VWR International sells Snowpacks through its UK distributor. The version that makes 30 g pellets of dry ice is catalogue number 3285042/02.

Philip Harris sells similar products, see catalogue number C7A57812. (The dry ice attachment comes with safety gloves).

2.Buying blocks or pellets

Blocks of solid carbon dioxide or granulated versions of it can be obtained fairly easily with a search on the Internet. Local stage supply shops or Universities may be able to help. It usually comes in expanded foam packing; you can keep it in this packing in a deep freeze for a few days.

The dry ice pellets come in quite large batches. However, they have a number of uses in science lessons so it is worth trying to co-ordinate the activities of different teachers to make best use of your bulk purchase.

Answer 8

Take a CO2 fire extinguisher and spray it into a pillow case the white stuff in the pillow case when you're done is pure dry ice.

Answer 9

MAKE YOUR OWN DRY ICE with The Frost-Stick Dry Ice System and CO2:
http://www.frost-stick.com/#makeice


Dry ice manufacturing starts with liquid carbon dioxide held under pressure (300 psi) in bulk storage vessels. To begin making dry ice, the liquid C02, is sent through an expansion valve into an empty chamber where under normal atmospheric pressure it flashes into C02 gas. This change from liquid to gas causes the temperature to drop quickly. About 46% of the gas will freeze into dry ice snow. The rest of the C02 gas, 54%, is released into the atmosphere or recovered to be used again. The dry ice snow is then collected in a chamber where it is compressed into block, pellet or rice size pieces to meet customers requirements. The denser the dry ice is, the longer it will last, the easier it is to handle, and the better it will perform when blast cleaning.

There are three major types of dry ice machines. The first is a dry ice block maker. It can produce a 220 pound solid block which is usually cut into four 55 pound blocks about 11 inches cubed Newer block machines make a 50 pound or even a 10 pound block. Next there are machines that produce pellets from smaller than 1/8 inch for dry ice blast cleaning to 3/4 inch in diameter. Sometimes these machines include additional parts for blast cleaning. There are four or five major manufacturers in the world. Several additional companies manufacture small dry ice makers that connect to a CO2 tank and make 5 to 10 pound blocks of lower density dry ice.

Charles Hyde of CO2 Air Equipment has developed a machine to produce airline size dry ice blocks with a pelletizer and reformer saving many band saw cuts and associated labor.

For a low cost alternative to making dry ice blocks you can even make dry ice snow yourself with a CO2 tank. Although it is not very efficient, just open the hose into a burlap bag, and then pack the dry ice snow into a container. This can be used to fill coolers, quick freeze food products before shipment, science projects, and many of the same uses as traditional higher density blocks of dry ice without the expensive hydraulics and capitol costs of a large dry ice maker. It will also save on storage loss through sublimation as it is only used when immediately needed.

Precautions:
You are using dry ice at your own risk.
Precautions for handling dry ice include:

* If your skin comes in contact with dry ice, frostbite will occur. If burned, contact a physician immediately.
* Do not transport dry ice in the cab of a truck or the passenger compartment of a car.
* If you are traveling in a sport utility vehicle or minivan, leave a window open to ventilate the vehicle.
* Always ensure that there is adequate ventilation so that carbon dioxide gas can escape.
* To dispose of any remaining dry ice, remove the bag containing the dry ice and place in a trash container outside of your home.
* Always keep dry ice away from children and pets.
* Do not put dry ice in a sealed container. Expanding gas may cause dangerous bursting of container.
* Inhalation of excess Carbon Dioxide may cause you to pass out or suffocate. Move victim to a well ventilated area off the ground. Call a physician immediately.

Answer 10

Dangerous, but this is how it can be done.

Typed the answer, then erased it. I don't want to contribute to someone being harmed. Just go buy your dry ice from a local ice maker.

Answer 11

Dry Ice is the solid state of Carbon dioxide. To make it at home, you have to take some CO2 and freeze it. Be careful, it might be dangerous.