Process for isolation of pure substances from mixtures of high- boiling air and/or temperature-sensitive substances which require a high separation efficiency by rectification under medium vacuum, and columns suitable for this process

摘要

Process for isolating pure substances from of mixtures of high- boiling air- and/or temperature-sensitive substances which require a high separation efficiency, by rectification under medium vacuum in columns containing metal cloth packings with ordered structure using channel liquid distributors with 500 or more drip points/m.sup.2, which are arranged at an angle of 90 to the cloth layers of the packing elements located immediately below the distributors, in which two or more of the packing elements underneath the liquid distributors have only a very small height, which ensure virtual exclusion of air and are designed so that no heat exchange through the column wall can take place during the rectification. The patent also relates to packed columns which can be used for this process and to the use of this process and these columns for the final purification of vitamin E acetate by distillation.