How it works
How is dry ice made?
From liquid carbon dioxide to solid blocks and pellets — the surprisingly simple way dry ice is produced.
Get a freight quoteDry ice is the solid form of carbon dioxide (CO₂) — the same gas plants breathe in and we breathe out. Making it is a matter of taking CO₂ under pressure, letting it expand rapidly to form a cold "snow," and pressing that snow into the blocks, slices and pellets you use. Here is the process step by step.
From liquid CO₂ to solid dry ice
Dry ice production starts with liquid carbon dioxide, stored under high pressure. The process is mechanical and repeatable:
- Liquid CO₂ is held in pressurized tanks, often captured as a by-product of industrial processes.
- The liquid is released into a chamber at normal pressure, where it expands and rapidly cools.
- As it expands, part of the CO₂ flashes to gas and the rest freezes into fine, snow-like solid CO₂.
- A hydraulic press compacts the CO₂ snow into dense blocks, or extrudes it into slices and pellets.
- The finished dry ice is stored in insulated containers until it’s used — it has no shelf life, only a sublimation rate.
Why it sublimates instead of melting
Dry ice sits at about −109°F (−78°C). At normal atmospheric pressure, solid CO₂ can’t exist as a liquid — it goes straight from solid to gas, a change called sublimation. That’s why dry ice "disappears" without leaving a puddle: it turns into harmless CO₂ gas. It’s also why a sealed, airtight container is dangerous (the gas needs to escape) and why ventilation matters in an enclosed space.
Frequently asked questions
What is dry ice made of?
Dry ice is solid carbon dioxide (CO₂) — nothing else. It is the frozen form of the same CO₂ gas that exists in the air, compressed and frozen to about −109°F (−78°C).
Why is it called "dry" ice?
Because it never becomes wet. Instead of melting into liquid like water ice, it sublimates — it turns directly from solid into CO₂ gas — so it leaves no water behind.
How long does dry ice last?
It depends on the quantity, the insulation and the surrounding temperature. As a rule of thumb, dry ice sublimates at roughly 5–10 pounds per day in a typical cooler, faster in warm or open conditions. We size your supply so it lasts as long as you need.
Can I make dry ice myself?
Producing dry ice safely requires pressurized liquid CO₂ and the right equipment, so it isn’t a practical DIY project. The simpler route is to order it: RS Group supplies dry ice in blocks, slices and pellets, with compliant handling and shipping.
More on dry ice
Need a dry ice supply?
Skip the production and order it from us — tell us your volume and timing, or call our team.