You breath it out, plants breath it in. They don't grow without it. You can use items placed in Gas Filter slots to remove this from the atmosphere. Carbon Dioxide has a moderately high specific heat, meaning it makes a good coolant for devices like the Wall Cooler. Water is better, but usually has more important uses.

Description

Carbon Dioxide
Phase Change Information
Specific Heat	28.2 J/mol*K
Latent Heat	600 J/mol
Min Condensation Pressure	517 kPa at 217.82 K
Max Liquid Temperature	6000 kPa at 265 K
Freezes at	217.82 K
Liquid Volume	40 L/kmol
Molar Mass	44 g/mol
	v; t; e;

Carbon Dioxide, also referred to as CO₂, is a non-flammable gas found in some atmospheres naturally (such as Mars). It can also be produced by burning Fuel or Coal, smelting most ores (e.g. Iron, Copper, and Silicon) and through human respiration.

Details

Carbon Dioxide will condense into Liquid Carbon Dioxide starting at 265 K (-8.1 °C). With such a low temperature requirement, most setups will store Carbon Dioxide as a gas and use Liquid Carbon Dioxide as a coolant.

Carbon Dioxide is required for most plants to grow. Plants will inhale the Carbon Dioxide to create Oxygen which can be harvested using vents. Stationeers should monitor their plants to ensure they always have enough Carbon Dioxide as, given enough time, they can convert all of it into Oxygen.

Carbon Dioxide has an isochoric molar heat capacity of 28.2 J/mol⋅K, making it a superior coolant to Pollutant outside applications involving phase change where Pollutant can make use of its greater latent heat capacity. Both are greatly surpassed by water, though water is harder to find and has more important uses.

Sources

You can collect Carbon Dioxide from the following sources:

Source	Amount
Coal Ore	10 mol
Charcoal	3 mol
Copper Ore	1 mol
Gold Ore	0.2 mol
Iron Ore	0.5 mol
Lead Ore	0.4 mol
Nickel Ore	1 mol
Silicon Ore	1 mol

Gases and Liquids
Elements	Compounds	Mixtures	Other
		Fuel (66.6% H₂ + 33.3% O₂) Superfuel (50% H₂ + 50% N₂O) Air (75% N₂ + 25% O₂)	Atmosphere Coolant