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Usage of glass distillation unit: clean the instrument and fix it with iron frame. If the bottom of the flask is heated by gas or electric furnace, an asbestos net shall be padded, and the volume of the liquid put into the flask shall not exceed 2 / 3 of

Ordinary distillation has bubble and boiling phenomenon, while molecular distillation is the free evaporation on the surface of liquid film, with low operating pressure, generally 0.1-1pa order of magnitude and short heating time. Generally, it is only te