hydrothermal pretreatment of biomass for ethanol fermentation · 1 biomass project research center,...

Biomass Project Research Center, Hiroshima Univ. 1

Hydrothermal pretreatment of biomass

for ethanol fermentation

Dec. 10-12, 2012

JAPANESE-DANISH JOINT WORKSHOP “Future Green Technology”

Hakata, Japan

Yukihiko Matsumura

Hiroshima University


First generation Second generation

•Sugar, Starch, grain

•Easy fermentation to bioethanol

•High price raw material

•Competition with foods

•Lignocellulosic residues (wood,

straw) and other agricultural

residues

•Advanced technology is needed

緒言 First and second generation ethanol

Biomass Project Research Center, Hiroshima Univ. 3 3

Enzymatic

hydrolysis Hemicellulose

Lignin

Lignocellulosics

Ethanol

Ethanol

fermentation

CH2OH

HOH

OH

OHOH

HH

H

H

Glucose

O

OH

OH

HO

CH2OH

O

O

OH

OH

CH2OH

O

OH

OH

CH2OH

O OH

n-2

Cellulose

緒言 Saccharification of lignocellulosics

Pretreatment


Pretreatment Concept Disadvantage Author (year)

Previous study

Concentrated

sulfuric acid

Promote hydrolysis with

concentrated sulfuric acid

・Decomposition of glucose

by acid

・ High cost to use acids

Gupta R et al.

(2009)

Dilute sulfuric

acid

Promote hydrolysis with

dilute sulfuric acid

・High cost to treat

byproducts

・Reactor corrosion

Root et al. (1959)

Steam explosion After heating up in steam,

suddenly reduce the

pressure

・Low glucose yield DeLong (1981)

Pulverization Decrease the crystallinity of

cellulose

・Large amount of energy

needed.

Sidiras and Koukios

(1989)

Hydrothermal Hemicellulose is dissolved

in water by high

temperature and pressure.

Reduction of crystallinity of

cellulose.

・Low cost

・Low glucose yield

Mok and Antal

(1994)

Various pretreatment for saccharification


Hydrothermal

Pretreatment

Enzymatic

hydrolysis Ethanol

fermentation

Lignocellulosic

biomass Cellulosic

component

Monosaccharide

Ethanol

Inhibitors

Inhibitor byproducts for fermentation


Fermentation inhibitors are produced during

hydrothermal pretreatment, which affects the activities

of the yeast

Inhibitors Formic acid, Acetic acid, Furfural , 5-HMF

Yeast Saccharomyces cerevisiae

Anaerobic

Aerobic

Ethanol fermentation

Cell growth

Fermentation inhibitors

//upload.wikimedia.org/wikipedia/ja/0/09/Saccharomyces_cerevisiae.jpg


This evaluation has not been reported so far.

To commercialize the process, reaction characteristics

as well as inhibitor effect should be clarified.

but･･･

The purpose of this study is to determine the

reaction characteristics and inhibitor effect

quantitatively.

Purpose of this study

Purpose


Raw materialRubber wood residues

Hydrothermal pretreatment

Filtration

Liquid fraction Solid fraction

Glucose product

Glucose productEnzymatic hydrolysis

Autoclave reactor

The working volume of the pretreatment

vessel was 96 mL. The pretreatment

agitator was set at 500 rpm. Reactant 1 g

Buffer fluid 60 mL

10 g/L cellulase solution 5 mL

Enzymatic hydrolysis

Cellulase from Aspergillus niger powder,

≥0.3 units/mg solid

The flasks were shaken at 250 rpm at 37 C

HPLC with SUGAR K S-802(Shodex)

column operated at 60 °C with

0.8mL/min flow of water as an eluate. The

detector was a refractive index

Experimental for hydrothermal pretreatment


Temperature 130, 150, 170, 190, 200, 210, 240, 260 and 280 oC

Rubber wood powder 7 g

De-ionized water 63 g

0

50

100

150

200

250

300

0 50 100

Tem

per

atu

re [℃

]

Time [min]

130°C140°C150°C170°C190°C200°C210°C240°C260°C280°C

Temperature history for different target temperatures.

Experimental conditions


Rubber wood

residue 37% of market share export of

the world are from Thailand

Composition %

hemicelluloses 29

lignin 28

cellulose 39

ash 4

CHEMICAL CHARCTERISTICS

OF RUBBER WOOD RESIDUE

•United States Department of Agriculture, “Forage fiber analyses

(Apparatus, reagents, procedures, and some applications)”,

Agriculture Handbook, 379 (1970)

Feedstock

http://www.doa.go.th/pl_data/RUBBER/IMAGE/rubber20.jpg


A B C

A B C D E

The samples after

hydrothermal pretreatment

at temperature on 130 (A),

140 (B), 150 (C), 170 (D),

and 190°C (E)

D E

0

0.02

0.04

0.06

0.08

0.1

0.12

0.14

0.16

0 24 48

Yie

ld [

-]

Time of cellulase reaction [hour]

HC 130 °C

HC 140°C

HC 150°C

HC 170°C

HC 190°C

HC 200°C

HC 210°C

HC 240°C

HC 250°C

HC 260°C

HC 280°C

Time dependence of amount of glucose generated

from solid residue treated temperature 130–280oC,

10 wt% of concentration of raw material, treatment

time 0 min. (HC denote the solid sample from

hydrothermal pretreatment used with enzymatic

hydrolysis)

Products and saccharification


C G D

C*

1 k

3 k

2 k 4 k

) / exp( RT E A k ⊿ - =

C G D

C*

1

3

2 4

) / exp( RT E A k =

C Cellulose

C* Cellulose hydrolyzed by cellulase after pretreatment

G Glucose

D Decomposition products of glucose

C

C*

C

G

D

G

C*

C

DH

yd

roth

erm

al

pre

tre

atm

en

t

Cellu

las

e t

reatm

en

t

Reaction modeling


][][][

21 CkCkdt

Cd

][][*][][

423 GkCkCkdt

Gd

*][][*][

31 CkCkdt

Cd

][][

4 Gkdt

Dd

Preexponential

factor

[1/s]

Activation

energy

[kJ/mol]

k1 1.87×105 62.0

k2 2.02×107 87.7

k3 1.80×1018 222.2

k4 2.88×102 14.4

Reaction rate parameters

0

0.2

0.4

0.6

0.8

1

120 140 160 180 200 220 240 260 280 300

Temperature [oC]

Yie

ld [

-]

C C* G

D

Reaction rate parameters


0.00

0.20

0.40

0.60

0.80

1.00

140 150 160 170 180 190 200 210

Pretreatment Temp [℃]

Yie

ld [

-] C

C*

G

D

0.00

0.20

0.40

0.60

0.80

1.00

160 170 180 190 200 210 220 230 240


Yie

ld [

-] C

C*

G

D

Cabbage

EFB

0.00

0.20

0.40

0.60

0.80

1.00

150 160 170 180 190 200 210 220 230


Yie

ld [

-] C

C*

G

D

Kenaf

0

0.2

0.4

0.6

0.8

1

120140160180200220240260280300

Temperature [oC]

Yie

ld [

-]

C C* G

D

Comparison with other feedstocks


Model for the reactions in hydrothermal pretreatment

reactor was proposed.

The reaction parameter in the hydrothermal reactor for

rubber wood was successfully decided.

Reaction characteristics differs from feedstock to

feedstock.

緒言 Conclusions (reaction characteristics)


5 wt%YPD

10 mL rotary shaker, 30 ℃

incubator

Yeast

0.2 mL

Fermentatio

n inhibitor

Glucose and

ethanol

concentration

by HPLC

14 mL

vial

OD at 600 nm

緒言 Experiment for inhibitor effect clarification


Yeast

YPD medium (5.0 wt%)

Preculture

Formic acid

Acetic acid,

Furfural

5-HMF

Measuring time

Incubation temperature

S. cerevisiae *

10 mL

0.2 mL

0-45 mM

0-45 mM

0-45 mM

0-15 mM

36 h

30 oC

Inhibitor concentration

*Sigma-Aldrich (Type II)

緒言 Experimental conditions


μ=μmax KS

S

Xdt

dXμ

dt

dX

dt

dSk

（Monod equation）

XXoSo

k

SokXo

K

Xo

X

SokXo

K

1lnln)1(

μmax

1

X：Cell concentration

X０：Initial Cell concentration

S：Culture medium concentration

S０：Initial culture medium concentration

t： Incubation time

μmax: Maximum growth rate

K：Half medium concentration rate

k：

τ： Lag phase time

(1) Lag phase (2) Exponential growth phase

(3) Resting phase

)( τt

(1) (2) (3)

Time [h]

OD

at

600 n

m

τ

μmax

K

k

緒言 Cell growth model


Formic acid Acetic acid

0

0.1

0.2

0.3

0.4

0.5

0.6

0 10 20 30 40

OD

at

60

0 n

m [

-]

Time [h]

0 mM

15 mM

30 mM

45 mM 0

0.1

0.2

0.3

0.4

0.5

0.6

0 10 20 30 40O

D a

t 6

00

nm

[-]

Time [h]

0 mM 15 mM

30 mM

45 mM

緒言 Inhibitor effect on cell growth


Furfural 5-HMF

0

0.1

0.2

0.3

0.4

0.5

0.6

0 10 20 30 40

OD

at

60

0 n

m [

-]

Time [h]

0 mM

15 mM

30 mM

45 mM

0

0.1

0.2

0.3

0.4

0.5

0.6

0 10 20 30 40O

D a

t 6

00

nm

[-]

Time [h]

0 mM

5 mM

10 mM

15 mM

緒言 Inhibitor effect on cell growth


0.00

0.02

0.04

0.06

0.08

0.10

0.12

0.14

0.16

0.18

0 20 40

K/S

0 [

-]

Concentration [mM]

0.00

1.00

2.00

3.00

4.00

5.00

6.00

7.00

8.00

9.00

10.00

0 20 40

k/S0

[-]

Concentration [mM]

0.00

0.10

0.20

0.30

0.40

0.50

0.60

0 20 40

μm

ax [

1/h

]

Concentration [mM]

Formic acid Acetic acid Furfural 5-HMF

0.00

2.00

4.00

6.00

8.00

10.00

12.00

14.00

16.00

0 20 40

τ [h

]

Concentration [mM]

緒言 Monod parameter change by inhigibors


Formic acid Acetic acid

0 mM 15 mM 30 mM 45 mM

Ethanol

Glucose

0

0.05

0.1

0.15

0.2

0.25

0.3

0 10 20 30 40

Co

nce

ntr

atio

n [

mo

l/L]

Time [h]

0

0.05

0.1

0.15

0.2

0.25

0.3

0 10 20 30 40

Co

nce

ntr

atio

n [

mo

l/L]

Time [h]

緒言 Inhibitor effect on ethanol fermentation


Furfural 5-HMF

0

0.05

0.1

0.15

0.2

0.25

0.3

0 10 20 30 40

Co

nce

ntr

atio

n [

mo

l/L]

Time [h]

0

0.05

0.1

0.15

0.2

0.25

0.3

0 10 20 30 40

Co

nce

ntr

atio

n [

mo

l/L]

Time [h]

Furfural 0 mM 15 mM 30 mM 45 mM

5-HMF 0 mM 5 mM 10 mM 15 mM

Ethanol

Glucose

緒言 Inhibitor effect on ethanol fermentation


• The inhibitors used in this study slows cell growth

and final yeast concentration. Effect on

parameters were observed (μmax , k, τ).

• The inhibitors used in this study except acetic acid

decreases glucose consumption rate and ethanol

production rate for ethanol fermentation.

• Acetic acid affects cell growth but does not affect

ethanol production.

緒言 Conclusions (inhibitor effect)


This study was supported by the following funds.

Ministry of Education

Collaborating bodies

Tawatchai Charinpanitkul (Chulalongkorn University)

Staffs and Students Takuya Yoshida, Machi Kanna, Takashi Yanagida

Phacharakamol Petchpradab

Yuta Fukutomi

緒言 Acknowledgment


緒言

Thank you!!

See you at the European Biomass Conf. and Exhibition, 3-7 June 2013

Bella Center - Copenhagen, Denmark

hydrothermal pretreatment of biomass for ethanol fermentation · 1 biomass project research center,...

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