Water as a leaching agent

The use of liquid water at a high temperature and pressure provides a promising alternative to other sample pretreatments as this is the ideal solvent for developing environmentally friendly methods. Water at a high pressure and temperature has traditionally been called subcritical water however, the term superheated water is probably more accurate to refer to water heated above 100°C and subjected to the pressure required to keep it in the liquid state as subcritical water can be any water below the critical point 

High-pressure, high-temperature solvent extraction 

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