Improved mass transfer for supercritical-fluid extraction— A new mixer-settler system

摘要

The efficiency of conventional countercurrent extraction-columns is relatively poor when using highly compressed gases, in particular as a consequence of substantial longitudinal mixing and film detachment. It is therefore obvious that the apparatus must be adapted to the supercritical conditions. A mixer-settler module, consisting of a regenerative pump and a fluid cyclone, which is more suitable than a countercurrent column for supercritical systems, was thus developed and dimensioned in this project. Murphree efficiencies of 81 and 96% were found for a module of this type on the synthetic test system α- tocopherol-α-tocopherol acetate-C02. The same module was also suitable as an equilibrium apparatus for the requisite phase-equilibrium measurements.