Ethanol Production from Grain and Biomass Constance Schall Dept' of Chemical

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Ethanol Production from Grain and
BiomassConstance SchallDept. of Chemical
Environmental EngineeringUniversity of Toledo
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Grains vs. Biomass
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Renewable Energy

• Wind
• Solar
• Geothermal
• Biomass
• Biomass can serve as a source of chemicals and
  transportation fuels

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Biomass to Fuels

• Traditional Ethanol Production
• Why use biomass as a carbon/sugar source?
• Biomass research at the University of Toledo
• Challenges and Opportunities

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Traditional ethanol production from starch based
crops
Ethanol
Distillers Dried Grains with Solubles
CO2
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Why produce ethanol from corn?

• The starch in corn grain is easily hydrolyzed to
  sugar (glucose).
• Enzymes used to convert starch to sugar are low
  cost.
• Sugar is fermented to ethanol by well established
  methods.

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Limitations of Ethanol from Corn

• National Energy Policy - Displace 30 of US
  gasoline consumption with ethanol by 2030 (60
  billion gallons of ethanol)
• In 2004 11 of US corn harvest yielded 1.7 of
  the transportation fuel demand
• 100 of corn harvest yields 15 of fuel demand
• Alternative source - biomass

From Biomass to Biofuels, Biomass to Biofuels
Workshop, (2005), Rockville, MD, Office of
Science, US DOE
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Lignocellulosic Biomass
Yield of Ethanol Corn 416 gal /acre Biomass 800
gal/acre USDA estimates 1.4 billion tons
biomass can be produced, yielding 80 billion
gallons ethanol
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What is Biomass?
Cellulose Highly crystalline
(30-45) polymer of glucose (hexose) a source
of fermentable sugar
Hemicellulose Amorphous polymer of (20-30)
xylose and other sugars (fermentable sugars)
Lignin A cross-linked polymer network (10-25)
of phenyl propanoid subunits
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Ethanol from Biomass
Biomass

• Pretreatment Cellulose Hydrolysis - critical
  steps
• Fermentation is more complex since biomass
  produces a mixture of sugars.

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Highlights of Biomass Research at the University
of Toledo

• Novel ionic liquid pretreatment process
• Fermentation of mixed sugars
• Separation of fermentation inhibitors

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Biomass Pretreatment
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Biomass Dissolution Regeneration
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Conversion of biomass to sugar
Slow conversion
Fast conversion
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Research Team

• Constance Schall Anantha Dadi
• Sasidhar Varanasi Kripa Rao
• Jared Anderson Noureen Faizee
• Indira Samayan
• Amy Coxe
• Bradley Yaniga

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Fermentation of mixed sugarsSasidhar Varanasi,
Kripa Rao, Silpa Chelikani, and Patricia Relue

• Glucose and xylose sugars produced from biomass
  can be fermented to ethanol.
• Industrial yeast ferments glucose easily.
  Conversion of xylose to xylulose allows
  fermentation of xylose.
• Convert xylose to xylulose in the same step as
  fermentation or hydrolysis.

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Optimal pH differs for xylose conversion and
fermentation. Local pH maintained for xylose
conversion.
Fermentation broth, pH 4-5 pH0
Zone1 R1 Zone2
R2
pH
pH0
pH1
r
R1
R2
Pellet system maintains a pH gradient between the
solution and the pellet.
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Membrane reactors in biofuels Glenn Lipscomb

• Dilute acid pretreatment of biomass produces
  by-products detrimental to fermentation are
  removed by neutralization or conditioning

http//www1.eere.energy.gov/biomass/dilute_acid.ht
ml
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Membrane Reactor

• Membrane reactor removes acidic by-products by
  esterification

Hydrolysate Acid by-products
Purified hydrolysate
Membrane Reactor
Alcohol
Ester
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Novel Catalytic Membrane

• Introduce acidic PolyOxoMetalates (POM) into
  membrane to catalyze esterification

Hexametalate structure (MO6). Many choices for
the metal (green) exist
Poly(ether ether ketone) (PEEK, upper) and
sulfonated PEEK (lower) polymers

• Membrane immobilizes catalyst and provides high
  surface for contacting
• Same membrane can be used to catalyze biodiesel
  production

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Challenges Opportunities

• Production of transportation fuels from renewable
  sources can displace up to half of fossil fuel
  imports.
• Fuel can be produced from grains or biomass
• Ohio has the agricultural, academic and
  manufacturing base to play a major part in fuel
  production from renewables.
• Partnership between business, government and
  universities is needed to ensure a leadership
  position for Ohio in developing new technologies
  needed in fuel production from biomass.