Transcript Slide 1

LOUISIANA TECH UNIVERSITY
COLLEGE OF ENGINEERING & SCIENCE
Large Scale Reactors to Reduce
Cellulosic Ethanol Costs
College of Engineering and Science
Dr. James D. Palmer, Dr. Yuri Lvov, Dr. Hisham
Hegab, Dr. Dale Snow
Qi Xing, Dezhi Zhang, Joe Nealy, Bam Aryal
November 5, 2009
LOUISIANA TECH UNIVERSITY
COLLEGE OF ENGINEERING & SCIENCE
Ethanol for Fuel
•Sugar (Current technology) – fermented
from sugar (corn or sugar cane)
•Cellulose – waste biomass, wood,
switchgrass
•Does not compete with food
•Reduces Green-House Gas emissions
by 86%
•Cellulose must be converted to sugars –
then fermented as normal
LOUISIANA TECH UNIVERSITY
COLLEGE OF ENGINEERING & SCIENCE
Sugar (glucose)
Carbon Dioxide
H
H C OH
C
H
H
C
HO
O
OH
CH
OH
C
H
H
C
OH
Ethanol
Cellulose
O
LOUISIANA TECH UNIVERSITY
COLLEGE OF ENGINEERING & SCIENCE
Cellulosic Ethanol
•Priority by Department of Energy (2 billion gal. –
2013, 16 billion gal. – 2022)
•Best Technology uses Expensive Enzymes –
Iogen, Genencor, Novozymes
•“Free Enzyme” can only be used one time or
Immobilized onto surface to Reuse
•Estimated savings by Reusing ~$32 million each
ethanol plant, or $7.5 billion in nation
•June 2002 NREL technical report NREL/TP-510-324388 “Lignocellulosic Biomass to Ethanol Process Design and Economics
utilizing Co-Current Dilute Acid Prehydrolysis and Enzymatic Hydroylsis for Corn Stover
LOUISIANA TECH UNIVERSITY
COLLEGE OF ENGINEERING & SCIENCE
Layer-by-Layer Nano Self-Assembly
For Enzyme Immobilization
•LbL can be reapplied easily in manufacturing environment (large
scale)
- - - - - - - - - - - - Enzymes
•LbL applicable to mixture of enzymes
++++ + + ++ + + + +
- - - - - - - - - - - - ++++ + + ++ + + + +
Polyelectrolytes
Enzymes
- - - - - - - - - - - - -
Polyelectrolytes
LOUISIANA TECH UNIVERSITY
COLLEGE OF ENGINEERING & SCIENCE
Mean Zeta Potential Cellulase
(mV)
Accomplishments
•
•
20
0
-20
-40
-60
-80
-100
Layer
30.00
Thickness (nm)
•
QCM and Zeta potential confirm LbL
immobilization is effective
Free enzyme batch reactor data for
benchmark (one commercial enzyme
MUCH more active than others tested)
Immobilized enzyme batch reactor
data
Pre-treatment methods (base, acid,
ultrasound) – very big impact on
conversion!
Zeta Potential (mV)
•
40
Thickness
25.00
20.00
15.00
10.00
5.00
0.00
Layer
LOUISIANA TECH UNIVERSITY
COLLEGE OF ENGINEERING & SCIENCE
Free Enzyme
0.4
Conversion
Immobilized enzyme is
lower than “free” enzyme;
this is expected, savings
calculated assumed 10x
less activity!
0.3
0.2
0.1
0
0
1000
2000
Conversion
Immobilized Enzyme - 5 layers
0.12
0.1
0.08
0.06
0.04
0.02
0
0
1000
2000
3000
4000
5000
Time (min)
6000
7000
3000
4000
Time (min)
8000
9000
5000
6000
LOUISIANA TECH UNIVERSITY
COLLEGE OF ENGINEERING & SCIENCE
Future Work
Ultrasound Pretreatment
Average particle
size (microns)
• Nanotechnology
opportunities to improve
activity
• Impact of pre-treatments
• Test cellulose from wood
mills (other commercial
sources)
30
25
20
15
10
5
0
0
50
Time (min)
100
LOUISIANA TECH UNIVERSITY
COLLEGE OF ENGINEERING & SCIENCE
Questions?
Comments?
LOUISIANA TECH UNIVERSITY
COLLEGE OF ENGINEERING & SCIENCE
Polyelectrolytes Studied
Polycations
Polyanions
PVS
SO-3 K+
PSS
Polystyrenesulfonate
Polyvinylsulfate
SO-3 Na+
PDDA
PAH
N
H2+
PEI
N
NH3
+
Cl
Polyallylamine
-
Polyethylenimine
Cl CH3
CH3
Polydiallyldimethylammonium