Procesos de extracción con fluidos supercríticos asistidos por ultrasonidos de elevada intensidad. Problemas de escalamiento a nivel semi-industrial

Supercritical fluid extraction (SFE) is a recent technology that is based on the solvent power that some fluids exhibit under pressure and temperature above certain values named as critical point. This process, using supercritical CO₂ as solvent, has gained wide acceptance in the last years, because of its advantages compared to conventional solvent extraction ones. Nevertheless one of the difficulties of SFE is to achieve favourable kinetics due to the fact that mechanical stirring is not easily applied to an extractor vessel operating at high pressures. An interesting alternative is the use of power ultrasound (HPU). Ultrasonic radiation represents an efficient way to enhance mass transfer processes, because of mechanisms such as acoustic streaming, turbulence, radiation pressure, compressions and decompressions in the material, heat and/or cavitation.