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Renin Angiotensin Mechanism.

Definition and Applications of Distillation.

 

Definition:

  • The process of heating a liquid mixture to form vapor and then cooling that vapor to get a liquid is called simple distillation.

    • Distillation process involves separation of two liquids with different vapor pressures from a mixture, by boiling one to convert to vapors and condensing the vapors to gain the liquid back, hence separating the mixture.

    • 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”.

N.B. 

  • In practice it is difficult to distinguish between evaporation, distillation and drying.

  • Based on the intention:

    • When condensation vapor is required the operation is called distillation.

    • When the concentrated liquid residue is required the operation is called evaporation.

    • When the dried solid residue is required as a product the process is called drying.

Objectives of Distillation:

  1. Separation of fluids from mixtures.

  2. Extraction of active chemical constituents.

  3. Water Purification.

  4. Product purification.

  5. Recovery of expensive solvents.

  6. Recovery and recycling of the reactants and solvents.

Applications of Distillation:

  1. Recovery of Solvents:

    1. Many times expensive solvents are used for extraction of active chemical constituents from the crude drugs, distillation makes the process economical by recovering the costly solvents.

    2. Sometimes the used solvents if released into the atmosphere may have hazardous effects, distillation by recovering them minimizes the hazard of the operation.

  2. Extraction of the Volatile Oils:

    1. Many volatile oils like Clove Oil, Fennel Oil etc are extracted by using the process of steam distillation.

  3. Manufacturing of official preparations:

    1. Official preparations like Distilled water and Water for Injection are prepared by using distillation processes.

  4. Purification:

    1. Distillation processes can be employed for preparation of the pure products, e.g. Absolute alcohol.

  5. Quality Control:

    1. Distillation processes can be used to determine alcohol contents of the formulations like elixirs.

Commonly Asked Questions.

  1. Define distillation and write its application in pharmacy.
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