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A fractionating column or fractional column is equipment used in the distillation of liquid mixtures to separate the mixture into its component parts, or fractions, based on their differences in volatility. Fractionating columns are used in small-scale laboratory distillations as well as large-scale industrial distillations.
Here the distillation head and fractionating column are combined in one piece. Differential centrifugation . Fractionation is a separation process in which a certain quantity of a mixture (of gasses, solids, liquids, enzymes , or isotopes , or a suspension ) is divided during a phase transition , into a number of smaller quantities ( fractions ...
Robert Lemlich showed how foam fractionation columns can be operated in stripping, enriching, or combined modes (depending on whether the feed is sent to the top, bottom or middle of the column), and can be operated with or without an external reflux stream at the top of the column. It helps to think of the process as similar to a gas-liquid ...
The mixture is put into the round-bottomed flask along with a few anti-bumping granules (or a Teflon-coated magnetic stirrer bar if using magnetic stirring), and the fractionating column is fitted into the top. The fractional distillation column is set up with the heat source at the bottom of the still pot.
An overhead condenser is a heat exchange equipment used for condensing the mixture leaving the top of the column. Either cooling water or air is used as a cooling agent. An overhead accumulator is a horizontal pressure vessel containing the condensed mixture. Pumps can be used to control the reflux to the column.
Spinning band distillation takes this concept one step further by using a spinning helical band made of an inert material such as metal or Teflon to push the rising vapors and descending condensate to the sides of the column, coming into close contact with each other. This speeds up equilibration and provides for a greater number of ...
A fraction in chemistry is a quantity collected from a batch of a substance in a fractionating separation process. In such a process, a mixture is separated into fractions, which have compositions that vary according to a gradient. A fraction can be defined as a group of chemicals that have similar boiling points.
In industrial continuous fractionating columns, N t is determined by starting at either the top or bottom of the column and calculating material balances, heat balances and equilibrium flash vaporizations for each of the succession of equilibrium stages until the desired end product composition is achieved.