Solvent Replacement
See also Solvent Replacement, Water Resources Posters
An interesting application that falls between extraction and cleaning is the use of liquid carbon dioxide as a replacement solvent for drycleaning chemicals (See poster session on solvent replacement). During the development of supercritical cleaning technologies it was discovered that carbon dioxide in its liquid state is an excellent dry cleaning solvent.
- Dry cleaners currently use a chemical called perchloroethylene (also known as PERC), which is a suspected carcinogen. It is well known that residual amounts of PERC remain in clothing long after treatment. There are concerns as to the effect such a substance worn against the skin might have.
- After the PERC has been used, there remain large volumes of contaminated PERC that must be disposed of. Thus the dry cleaning industry is anxious to find alternative solvents.