Production of Second-Generation Biofuels from Palm Wastes

Production of Second-Generation Biofuels from Palm Wastes

Shinichi Yano

Biomass Technology Research Center, National Institute for Advanced Industrial Science and Technology, Japan

Biofuels Any fuels produced from biomass can be called biofuels, but recently, most of interests are focused on liquid biofuels for automobiles.

According to the differences of engines, totally 　different properties are required for biofuels.

●Biodiesel fuel (BDF) for diesel engines 　　　　　　　　　　　　 →　 High cetane number is required.

●Ethanol for Otto cycle engines. (engines for gasoline) → 　 High octane number is required.

What should be feedstock for liquid biofuels?

The present feedstock : Starch, or sugars for ethanol Vegetable oil, or animal fats for BDF First-generation biofuels (Converted by conventional technologies)

Problems1. Competition with food usage (supplies and costs)

2. Bumper crops or poor harvest → 　 instability

3. Can be real energy production? → LCA analysis is necessary.　　　　　　　　　　 　　　　　　　　　　　　　

Resources not for food or feed use. Lignocellulosic biomass (Wood wastes, Agricultural residues, Energy crops)

Second-generation biofuels　●　　 Cellulosic ethanol　●　 BTL （ Biomass to Liquid) diesel fuels However, several technological barriers exist for the production of Second-generation biofuels

Further R & D’s are required. 　　　　　　　　　　 　　　　　　　　　　　　　

Feedstock for the future

　 CHO

H 　　　　　OHOH 　　　　　

H　 H 　　　　　OH　 H 　　　　　OH CH ２

OH

Hydrolyzed products 　　　　　　　 →　 mainly D-xylose 　

Pentose sugars cannot be metabolized by Saccharomyces cerevisiae.

Technologies to overcome this problem are required.

　 CHO

H 　　　　　OHOH 　　　　　

H　 H 　　　　　OH　 CH ２ OH

Cellulose・ Crystalline・　 Difficult to hydrolyzeEfficient and low-cost technologies are required.

Cellulose・ Crystalline・　 Difficult to hydrolyzeEfficient and low-cost technologies are required.

LigninLignin

Hydrolyzed product 　　　　　　　 → D-glucose 　　　

Easily fermented to ethanol with conventional systems　　　

Hemicellulose・ Amorphous・ Relatively easy to hydrolyze

Hemicellulose・ Amorphous・ Relatively easy to hydrolyze

Two major technological barriers for the ethanol production from lignocellulosic biomass

Pretreatments

Pretreatments

Enzymatic　saccharificationEnzymatic　saccharification

Acid　hydrolysisAcid　hydrolysis

FermentationFermentation

Distillation/PurificationDistillation/Purification

EthanolEthanol ETBEETBE

Lignocellulosic biomassLignocellulosic biomass

Scheme for ethanol production from lignocellulose

Mechanical Milling TreatmentMechanical Milling Treatment

Hot-Compressed-Water Treatment

Hot-Compressed-Water Treatment

Technologies of AIST for pretreatments of lignocellulosic biomass

・ Separation of lignocellulosic components ・ Saccharification of hemicellulose

・ Separation of lignocellulosic components ・ Saccharification of hemicellulose

・ Pulverize to fine particles・ Change strurcture of cellulose

→Increasing reactivity of enzymes

・ Pulverize to fine particles・ Change strurcture of cellulose

→Increasing reactivity of enzymes

0 10 20 30 40

BM treatment

HCW treatment (200 , 30min)℃

0

100

200

300

400

500

Glu

cose

(m

g/g

of d

ry w

ood)

Cellulase loading (FPU/g of substrate)

Glucose　yields　from　pretreated　eucalyptus　powder　after　enzymatic　saccharification

O O O O O

OO

O O O

O O O O O O O O O O

O

O O

O O

O OOO OO OO

O O

Endoglucanase

　　（ for amorphous

region ） Exoglucanase　　（ for crystalline region ）

β-glucosidase　　　 (produce glucose ）

Cellulase: consists of three kinds of enzymes Synergetic effects of three enzymes are observed.

O

O

O O

O

O

････････　　･･････

････････　　･･････O OO OO OO O

O O O

For the cost reduction of cellulase

●Appropriate pretreatments

●Selection of enzymes and combination of enzymes

●On-site production of enzymes

Enzymatic saccharification

AIST original cellulase: Acremonium cellulaseAcremonium cellulolyticus :A fungi isolated from soil in Japan by Takashi Yamanobe, AIST, in 1982

Industrially produced by Meiji Seika Co. LTD.,mainly for silage preparation

Acremonium cellulase has higher 　　　　　　　 β-glucosidase activity than Trichoderma cellulase.

suitable for ethanol production

The research for elevating enzyme productivity is underway.

Improvement of enzyme productivitiy by mutation

FPU

CMCase-glucosidase

Avicelase

Parental strain Mutant

100%

200%

Enzyme activities /ml of cultures

0 100 200 300 400 500 600

Eucalyptus

Oak

Beech

Cedar

Japanese　cypress

Douglas　fir

Palm

GalAraManXylGlc

Sugar　(g/kg　dry　wood)

0 100 200 300 400 500 600

Eucalyptus

Oak

Beech

Cedar

Japanese　cypress

Douglas　fir

Palm

GalAraManXylGlc

Sugar　(g/kg　dry　wood)

0 100 200 300 400 500 600

Eucalyptus

Oak

Beech

Cedar

Japanese　cypress

Douglas　fir

Palm

GalAraManXylGlc

Sugar　(g/kg　dry　wood)

Sugar yields from BM-treated wood powder after enzymatic saccharification

4FPU/g 40FPU/g 4FPU/g 40FPU/gComposition Composition

Su

gar

yie

ld (

g/g

dry

ma

teri

als

)

Sugar yields from BM-treated palm-trunk and EFB fiber after enzymatic saccharification (4 or 40FPU/g)

Saccharification rate: Glucose 57%, Xylose 72% Glucose 42%, Xylose 42%

RCOO-CH2

RCOO-CH

RCOO-CH2

３ R-CH3 H2O

CH3-CH2-CH3

３ R-H3CO2 or

3CH4

CH3-CH2-CH3

+ ３ H2~+15H2+12H2

Dehydration Decarboxylation

Triglycerides

+3CH3OH

Hydro-treated biodiesel

New biodiesel fuels (1) Hydro-treated biodiesel

3RCOOCH3 (BDF)+

Glycerol

Palm hydro-treated diesel

Palm FAME

Diesel fuel(Japanese Standard-

2)

Density g/cm3 0.7852 0.8742 0.8283

Flash point 　℃ 132 180 75

Iodine value 0.1 59 0.0

Pour point 　℃ 20 15 -22.5

Viscosity

mm2/s@30℃4.140 5.510 4.063

Distilla-tion

T10℃ 284.5 333.0 221.0

T90℃ 301.0 359.0 337.5

Cetane number 101 62 60

Oxygen mass% <0.1 12 <0.1

Higher cetane number, higher stability, better quality, than FAME data from Nippon Oil Co. Ltd

Property of hydro-treated biodiesel

CO,　H2tar， S

PurificationCO,　H2

(100～ 400℃）gasification

～ 900℃

FT 　 synthesis

● Diesel fuels from lignocellulosic biomass● High quality, high cetane number

Biomass

New biodiesel fuels (2) Biomass to Liquid (BTL)

AIST’s bench-scale BTL production plant

　 AIST Chugoku

(Kure, Hiroshima)

Biomass Technology

Research Center

AIST has constructed bench-scale BTL production plant and started its operation this spring. The BTL production capacity is 1.9L/d.

Possible Second-generation Biofuel Production from Palm Wastes

Wasted　Trunk　Wasted　Trunk　

Empty　Fruit　Bunch

Empty　Fruit　Bunch

Oil PalmOil Palm

Fresh Fruit Bunch Fresh Fruit Bunch

Fruit Fruit

Fiber,　　ShellFiber,　　Shell

SaccharificationSaccharification

FermentationFermentation

PurificationPurification

PretreatmentPretreatment

ETHANOLETHANOL

Crude Palm Oil Palm Kernel

Crude Palm Oil Palm Kernel

GasificationGasificationL

ign

ocellu

losic B

iom

assL

ign

ocellu

losic B

iom

ass PurificationPurification

FT synthesisFT synthesis

UpgradingUpgrading

BTLBTL

Conclusions

The first-generation biofuels (BDF and ethanol from sugars or starch ) are used as alternatives of petroleum fuels for automobiles at the present time.

There will be problems, however, because their feedstock is also utilized as foods or feeds.

To solve those problems, the use of second-generation biofuels produced from lignocellolosic biomass is anticipated.

But there are some technical barriers to be overcome to produce them in large quantity with low costs. Further R&D’s are necessary.