| 摘要 |
Medium containing solute consisting or organic substances is brought into contact with a solvent consisting of substances that have a critical temperature in the range 5 to 152 DEG C and are gaseous at atmospheric temperature and atmospheric pressure to extract the solute from the medium, and the solute is separated from a mixture of extracts. The solute and solvent form a mixture having an additional gas-liquid coexistence region, the extraction is carried out by bringing the medium into contact with the solvent in the sub-critical phase of the solvent, and the subsequent separation is carried out by heating the mixture of extracts to temperatures higher than the critical temperature of the solvent and higher than the contact temperature by 5 to 30 DEG C. The method is particularly suitable for extracting tocopherol from vegetable fats and oils, in which case carbon dioxide may be the solvent.
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