What technique is well-suited for the economical separation of heat-sensitive materials possessing exceptionally high latent heats of vaporization__________________?
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Answer: A. Liquid extraction
Explanation
Liquid extraction avoids boiling the mixture, preventing thermal degradation of heat sensitive materials. High latent heats of vaporization make distillation economically prohibitive due to massive energy requirements. Transferring solute between immiscible liquid phases operates effectively at ambient thermal conditions. Liquid-liquid extraction exploits differences in chemical solubility rather than boiling point discrepancies. Latent heat represents the energy needed to phase change a substance without temperature alteration. Solvent recovery downstream usually requires careful handling but protects the primary sensitive solute.
Pharmaceutical manufacturing uses liquid extraction to isolate delicate antibiotics from fermentation broths. Biochemical refineries extract heat sensitive proteins and organic acids using selective organic solvents. Petrochemical complexes extract aromatic compounds from aliphatic streams at moderate ambient temperatures. Distillation requires vaporizing high latent heat components, consuming excessive and costly thermal energy. Evaporation removes volatile solvents by boiling, which would destroy heat sensitive solute molecules. Absorption transfers gas into liquid but does not address liquid phase heat sensitive extractions effectively.
- Subject
- Engineering
- Category
- Chemical Engineering
- Topic
- —
- Difficulty
- medium
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