CO_2-EXTRACTION TEST FACILITY FOR EXTRACTION PRESSURES UP TO 1000 BAR: EXPERIMENTS FOR THE EXTRACTION/DECAFFEINATION OF COCOA

摘要

From the literature it is known, that the solubility of substances in supercritical carbondioxide depends on the pressure and temperature of the solvent. Higher pressure and therefore higher density often improves the solubility of substances. Beyond this changes in interactions allow to extract molecules which are difficult to dissolve at lower pressures. Most of the larger production facilities work with pressures below 300 bar. The design pressures are limited to approx. 500 bar as the plant costs rise superproportionally with increasing pressure. This paper describes a pilot plant which was built in order to be able to examine new extraction areas, requirements specific to the plant, special chemical engineering features and economic effects.