How Subcritical Water Extraction compares to other extraction mediums

The unique attributes of the water molecules extend into the higher temperature region from 100 - 300 deg C. As temperature increases the Dielectric Constant lowers to approach that of more polar molecules such as ethanol and acetone.

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With increasing temperature subcritical water has greater solvating and diffusivity power than water. In this state it is an ideal extraction medium. Compared to supercritical CO2, subcritical water is an easier process to extract polar compounds. However, the compounds must have thermal stability at the higher temperatures compared to scCO2.