supercritical carbon dioxide as a dry cleaning agent/industrial solvent

[ab27]

I know this is kind of a technical subject, but it bears great meaning for enviornmentalists. If you have the time to read on this, its interesting and explains it.

[ame]http://en.wikipedia.org/wiki/Supercritical_carbon_dioxide[/ame]

While CO2 does contribute to greehouse gases, ect, using it for dry cleaning instead of carbon tetrachloride is much safer and more enviornmentally freindly. It also works in decaffeinating coffee. It will replace many hazardous carcinogenic chemicals used for organic solvents.

Here is a simple explanation. Phases of matter are simply solid, liquid, gas, ect. Chemists speak of the "gas phase" ect. Think of it as a pressure cooker. Water boils at 100C(212 F), but will boil at a higher temp if under pressure. Apply heat, and a solid turns liquid. But at a certain pressure, a liquid will not turn to a gas, no matter how hot it gets. So by combining temperature and pressure, a supercritical fluid is reached, which has the properties somewhere between a liquid and a gas. These properties give it much hope for the future for replacing many chemicals in use today.

[earthymom]

I'm glad you are studying chemistry. We need more people like you to help discover better, safer, environmentally sounder ways to make the things we need/use.