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Renin Angiotensin Mechanism.

Simple / Differential Distillation.

 

Definition:

  • Simple distillation is a process in which a single component from a liquid (or mixture) is converted into vapor, the vapor is transferred to another place and recovered by condensing it. 

    • The liquid to be distilled is called “Distilland”.

    • The liquid obtained after condensation of the vapors is called “Distillate” or “Condensate”.

    • The apparatus used for distillation is called “Distillator” or “Still”.

    • The arrangement used to cool the vapors is called “Condenser”.

    • The apparatus that collects the distillate is called a “Receiver”.

Apparatus for laboratory scale

  • It consists of a distillation flask with a side arm sloping downward that is connected to a condenser. 

  • The condensed vapors are collected in a flask called ‘receiver’. 

  • The whole apparatus is made of glass. 

  • A thermometer is fitted in the distillation flask to note down the temperature at which the vapors are distilled.

  • Bumping is avoided by adding small pieces of porcelain or porous pot before distillation.

Large scale equipment for simple distillation:

Construction

  • The still is made up of stainless steel, copper, or any other suitable material. 

  • A thermometer is fixed to the still to note the temperature of the boiling liquid. 

  • An observation window in the hood is helpful to the operator to see the level of the boiling liquid. 

  • The still is connected to a condenser and then to a receiver. 

  • The bottom of the still is jacketed through which steam is introduced to heat the still.

Working

  • A liquid to be distilled is filled into the still to ½ to 2/3rd of its volume. 

  • Bumping of the liquid is avoided by placing a few small pieces of porcelain or glasses before the distillation. 

  • Water is circulated through the condenser.

  • Steam is passed through the inlet. 

  • The contents are heated gradually. The liquid begins to boil after some time. 

  • The vapor begins to rise and passes into the condenser. 

  • The temperature rises very quickly and reaches the boiling point of that liquid. 

  • The vapor is condensed and collected into the receiver. 

Uses of Simple Distillation:

  1. Preparation of Water for Injection and Distilled water.

  2. Purification of organic solvents.

  3. Preparation of some official aromatic waters.

  4. To separate non volatile components from volatile liquids.

Advantages of Simple Distillation:

  1. Economical and simple to use.

  2. Low heat energy.

  3. Less time of operation.

Disadvantages of Simple Distillation:

  1. Presence of impurities in the final product.

  2. Higher energy consumption.

  3. May accelerate unwanted chemical reactions during the process.

  4. Not useful for the Azeotropic mixtures.


Commonly Asked Questions.

  1. Define distillation and write in detail about the simple distillation.

  2. With a well labelled diagram describe principle and working of the simple distillation.
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