M2

• RECRYSTALLIZATION OF IM

  • purification of compound
  • purify liquids
  • Compounds dissolved in a liquid
  • purifying nonvolatile (rapidly)
• RECRYSTALLIZATION PROCESS

  1. add activated charcoal (absorption of solute to solvent and filter)
  2. Cool down in rum temp
• RECRYSTALLIZATION CHARACTERISTICS

  1. dissolved well in Bp not in room temp
  2. dissolve impurities well in room temp
  3. must not react with the substance to be purified
  4. solvent should be volatile (oils or liquids evaporate rapidly)
  5. solvent should be inexpensive (water)
  6. solvent should not be dissolve insoluble impurities even at solvent BP. removed by gravity filtration
• BENZOIC ACID

  • topical antiseptics
  • anti-fungal antibacterial
  • preventives
• DISTILLATION

  • change the phase of compond
  • method separating mixture based on different conditions of liquid preparation.
  • not chemical reaction, but Physical separation process
• BOLLING POINT

  • liquid is converted to vapor form
• CONDENSATON

  gas to liquid
• Boiling

  • form bubbles
  • equal vapor pressure and atmospheric pressure

  evaporation

  • no bubble
  • vapor pressure less than atmospheric
• Distillation

  • simple
  • fractional
  • steam
  • vacuum
• simple distillation

  • method effective for mixture with different BP
• fractional distillation

  • similar BP
  • water purification (acetore + water)
  • oil refineries
• steam distillation

  • separate heat sensitive componds in a mixture
  • plant + oil extraction
• vacuum distillation

  • very high BP
  • extraction of oil + fragranes
  • low applied pressure, low bp
• Recrystallization is a method of purifying non-volatile organic solids
• Characteristics of a good recrystallization solvent:

  • Should not dissolve the substance to be purified at room temperature, but dissolve it well at the solvent's boiling point
  • Should dissolve soluble impurities well at room temperature
  • Should not dissolve insoluble impurities even at the solvent's boiling point, which can be removed by gravity filtration
  • Must not react with the substance to be purified
  • Should be volatile
  • Should be inexpensive
• Common solvents used in recrystallization follow the principle of "like dissolves like"
• Distillation is a method for separating mixtures based on differences in the conditions required to change the phase of components of the mixture
• Boiling point is the temperature at which the vapor pressure of a liquid becomes equal to the pressure of the surrounding area
• Types of distillation:

  • Simple Distillation: effective for mixtures with considerably different boiling points (ideal minimum difference of 25°C)
  • Fractional Distillation: used for mixtures of liquids with similar boiling points
  • Steam Distillation: separates heat-sensitive components in a mixture, used for plant extraction and oil extraction from plants
  • Vacuum Distillation: ideal for separating mixtures with very high boiling points by reducing pressure
• Extraction process involves the extraction of phytochemicals through solvent partitioning based on the polarity of solvents used
• Common solvent combinations include:

  • Water and EtoAC
  • Water and DCM
  • Water and Hexane
  • MeOH and Hexane