Chemical manufacturing processes

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Chemical manufacturing processes
Reactive
Extractive
Natural raw material
Formulation
2
Basis of separation

• Size
• Shape
• Charge
• Polarity
• Solubility
• Volatility
• Mobility

3
Classification of separation processes

• Based on position of equilibrium
• Equilibrium
• Non-equilibrium
• Based on nature of process streams
• Phase transfer
• Stream splitting

4
Separation processes

• Liquid-liquid extraction
• Adsorption
• Filtration
• Solid-liquid extraction (leaching)
• Elution chromatography
• Membrane separation processes
• Distillation
• Affinity separation processes
• Drying and evaporation
• Freeze-drying
• Precipitation
• Crystallization
• Electrophoresis
• Centrifugation
• Mechanical sieving

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Staged separations Phase transfer
Cross-current
Co-current
Rectification type
Counter-current
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Staged separations Stream splitting
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Liquid-liquid extraction

• Transfer of solute from on liquid to another
• Depends on the partition behavior of the solute
• Used when
• Solute and solvent have similar volatility
• Solute is thermolabile
• Solute and solvent form azeotropic mixture
• Solute concentration is low

8
Applications of Liquid-liquid extraction

• Separation of aromatics from hydrocarbons
• Purification of antibiotics
• Purification of aromatics such as benzene, xylene
  and toluene
• Protein purification using aqueous two-phase
  systems
• Purification of natural products
• Purification of dyes and pigments
• Metallurgical purifications

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Extractors
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Solvent systems

• Aqueous / non-aqueous systems
• Water/MIBK
• Water/acetone
• Water/chloroform
• Aqueous two-phase systems
• Sodium phosphate/PEG in water

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Solvent miscibility

• Completely miscible
• Unsuitable for extraction
• Immiscible
• Ideally suited for extraction
• Partially miscible
• Composition dependent
• Various possibilities
• Could be used for extraction

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Solute portioning
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Partially miscible solvent system
A, Acetone
F
K
J
P
H
Q
C, MIBK
Water, B
L
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More partially miscible solvent systems
A
A
C
B
C
B
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Liquid-liquid extraction Sequence of events

• Mixing or contacting
• Phase separation
• Collection of separate phases

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Liquid-liquid contacting

• Shaking the extraction device
• Using an stirred tank
• Counter-current liquid flow
• Agitated counter-current liquid flow
• Contacting across a porous structure
• Ultrasonic vibration

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Separation of phases

• Coalescence and phase separation due to density
  difference
• Coalescence and phase separation by centrifugal
  assistance
• Assisted coagulation of dispersed phase
• Separation by membrane

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Solute mass transport

• Rate depends on the specific interfacial area and
  mass transfer coefficient
• Rate k a ?C
• Both of these depend on system hydrodynamics