Donna Mae R. Galaez
BS ChE – 4
February 7, 2017
Different Types of Distillation
Distillation is a widely used method for separating the component substances from a liquid mixture by selective evaporation and condensation. To separate a mixture of liquids, the liquid can be heated to force components, which have different boiling points, into the gas phase.
Simple Distillation
The vapor is immediately channeled into a condenser. Consequently, the distillate is not pure but rather its composition is identical to the composition of the vapors at the given temperature and pressure. Fractional Distillation
It is used in order to separate the components compon ents by repeated vaporization-condensation vaporization-conden sation cycles within a packed fractionating column. This separation, by successive distillations, is also referred to as rectification. Hydrodistillation: Water Distillation
The material is completely immersed in water, which is boiled b y applying heat by b y direct fire, steam jacket, closed steam jacket, closed steam coil or open steam coil. The main characteristic of this process is that there is direct contact between b oiling water and plant material. Water And Steam Distillation
The steam can be generated gen erated either in a satellite boiler or within the still, although separated from the plant material. Direct Steam Distillation
As the name suggests, direct steam distillation is the process of distilling plant material with steam generated outside the still in a satellite steam generator generally referred to as a boiler. a boiler.
Vacuum Distillation
Some compounds have very high boiling points. To boil such compounds, it is often better to lower the pressure at which such compounds are boiled instead of increasing the temperature.
Donna Mae R. Galaez
BS ChE – 4
February 7, 2017
This technique is referred to as vacuum distillation and it is commonly found in the laboratory in the form of the rotary evaporator. Air-Sensitive Vacuum Distillation
Some compounds have high boiling points as well as being air sensitive. A simple vacuum distillation system can be used, whereby the va cuum is replaced with an inert gas after the distillation is complete. Short Path Distillation
It is a distillation technique that involves the distillate travelling a short distance, often only a few centimeters, and is normally done at reduced pressure. Zone Distillation
It is a distillation process in long container with partial melting of refined matter in moving liquid zone and condensation of vapor in the solid phase at condensate pulling in cold area. Azeotropic Distillation
Owing to the intermolecular attractions between molecules in the mixture, mixtures may have a higher or lower boiling point than either of their components. A mixture of this kind is called an azeotrope. When the liquids in the azeotrope evaporate, the vapor has the same composition as the mixture, so azeotropes cannot be distilled using simple distillation techniques. Extractive Distillation
A solvent that will mix freely with one component but not the other is added to the mixture. The new mixture can then be separated by distillation. Reactive Distillation
A chemical that will react with one agent but not to the other is added, creating a new mixture that can be separated by distillation. Finally, adding ionic salts may alter the volatilities of the compounds in the mix in such a way that they can be distilled. Catalytic Distillation The process by which the reactants are catalyzed while being distilled to continuously separate the products from the reactants. This method is used to assist equilibrium reactions to reach completion.
Donna Mae R. Galaez
BS ChE – 4
February 7, 2017
Based on the amount of compound fed to the columns: Batch Column Method
The feed to the column is provided in batch-wise manner. The distillation process gets carried out when a batch of feed is introduced to the column.
Continuous Column Method
The feed to the column is introduced continuously without any interruptions. A continuous operation is used commonly in the industrial applications.
References: Distillation. (n.d.). Retrieved February 7, 2017, from http://byjus.com/chemistry/distillation/
John, B. (n.d.). Types of Distillation. Retrieved February 7, 2017, from Sciencing: http://sciencing.com/types-distillation-6924000.html Sandhyarani, N. (2016, August 22). The Various Types of Distillation That are Worth Knowing. Retrieved February 7, 2017, from Buzzle: http://www.buzzle.com/articles/types-of-distillation.html Extraction Methods of Natural Essential Oils. Retrieved January 8, 2017, from: http://agritech.tnau.ac.in/horticulture/extraction_methods_natural_essential_oil.pdf
