Industrial Production of Citric Acid

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Industrial Production of Citric Acid

• Application of Citric Acid (text,p.524)
• Acidulant in food, confectionary, and beverage
  (75)
• Pharmaceutical (10), e.g. soluble aspirin
  preparation
• - industrial (15) complexes with metals such as
  iron and copper to be stabilizer of oil and fats.

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Citric Acid Production by Aerobic Bioprocesses
Wikipedia
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Industrial Production of Citric Acid

• Microorganism Aspergillus niger (mainly),
  Candida yeast (from carbohydrates or n-alkanes)
• Citric acid production is m
  , mainly take place under nitrogen
  and phosphate limitation after growth has ceased.
• Medium requirements for high production
• - Carbon source molasses or sugar solution.
• - Na-ferrocyanide is added to reduce Iron (1.3
  ppm) and manganese (lt0.1ppm).
• - High d
  concentration
• - High sugar concentration
• - pH .
• - 30 oC.

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Industrial Production of Citric Acid

• Bioreactor batch or fed-batch (100m3)
• 5-25X106 A. niger spores/L may be introduced to
  the fermentor.
• Aeration is provided to the fermenter by air
  sparging (0.1-0.4 vvm)
• Temperature is controlled by cooling coil.
• Agitation 50-100rpm to avoid s
  on molds.
• F is used to reduce substrate
  inhibition and prolong the production phase one
  or two days after growth cessation.
• Volumetric yield 130 kg/m3

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Industrial Production of Citric Acid
Separation - The biomass is separated by
filtration - The liquid is transferred to
recovery process - Separation of citric acid
from the liquid precipitation calcium
hydroxide is added to obtain calcium citrate
tetrahydrate ? wash the precipitate? dissolve
it with dilute sulfuric acid, yield citric acid
and calcium sulfate precipitate ? bleach and
crystallization ? anhydrous or monohydrate
citric acid.
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Industrial Production of Ethanol

• Application of Ethanol
• Medical
• Fuel
• - Industrial

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Ethanol Production by Anaerobic Bioprocesses
Glycolysis
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Industrial Production of Citric Acid

• Microorganism S. cerevisae for hexose
• Candida sp. for lactose or pentose
• Genetically modified E. coli
• Ethanol production is growth-associated with S.
  cerevisae.
• Medium requirements for high production
• - Carbon source sugar cane, starch materials
  (e.g. corn, wheat), cellulosic materials (?!).
  yield 0.51 g ethanol/g glucose.
• - N, P, minerals.
• - Anaerobic
• - 100g/L glucose are inhibitory for yeast.
• - 5 (v/v) of ethanol are inhibitory for yeast.
• - pH4-6 for 30-35 oC.

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Industrial Production of Citric Acid
Bioreactor batch, continuous or with cell
recycle 95 conversion of sugars with a
residence time of 40 h in batch reactor 21 h
in continuous reactor without cell recycle 1.6
h in continuous reactor with cell
cycle By-products glycerol, acetic acid,
succinic acid.
Separation - Distillation to obtaining 95
(w/w) of ethanol-water mixture, followed by -
Molecular sieves to removing water from the
mixture to get anhydrous ethanol.
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Ethanol Production http//www.cleantechblog.com/u
ploaded_images/production_process-718492.jpg