How is Carbon Dioxide Collected?

Question

I was wondering how C02 is collected? (for things like fire extinguishers, dry ice and such) Can it be taken directly from the air and "bottled", or does it need to come from chemical reactions?

Answer 1

Ultimately, plants collect Carbon Dioxide the best.
Through a chemical reaction, they create sugar
which they store (and use).

If you burn a plant, it will release CO2. Indeed,
burning coal and other plant products is a very
efficient way of obtaining CO2 for dry ice,
fire extinguishers, etc.

However, to collect it from their air, good old
vegetation can't be beat!

BTW, this is one of many reasons why killing
off the rain forests is such a bad idea (killing
trees kills a natural way of trapping CO2)
and planting trees is such a good idea.

It is now thought that humanity's release of so
much CO2 is the primary reason for global
warming.

Answer 2

All the different elements have different melting points, so air is fractionally distilled to get the different gases. Once they remove CO2 it is super cooled until it sublimes to a solid (dry ice).

Thats describing it really simply though