Effect of steam explosion pre-treatment on enzymatic saccharification of lignocellulosic material

(1)

METHODS:

RESULTS:

EFFECT OF STEAM EXPLOSION PRE-TREATMENT ON ENZYMATIC

SACCHARIFICATION OF LIGNOCELLULOSIC MATERIAL

Laurence Meyer

1

_{, Nicolas Jacquet}

1,2

_{, Caroline Vanderghem}

1

_{, Christophe Blecker}

2

_{, Michel Paquot}

1

1 _{Department of Industrial Biological Chemistry, Gembloux Agro Bio-Tech – Université de Liège, Gembloux, Belgium} 2 _{Department of Bio-resources valorisation, Gembloux Agro Bio-Tech – Université de Liège, Gembloux, Belgium}

INTRODUCTION AND OBJECTIVES:

•Saccharification of lignocellulosic raw material to produce biofuel requires fractionation of its complex structure by

pre-treatment.

•Steam explosion = thermomechanical process allowing breakdown of lignocellulosic material

by steam heating,

organic acids hydrolysis and shear stress.

•Aim  study the effect of steam explosion pre-treatment on the enzymatic hydrolysis of microcrystalline cellulose,

sugar beet pulp, miscanthus and corn straw.

0% 5% 10% 15% 20% 25% 30% 35% 0,00 5,00 10,00 15,00 20,00 25,00 Hyd rolysis % Time (h)

Microcrystalline cellulose (C200)

RAW MATERIAL

(<1MM)

STEAM EXPLODED

MATERIAL

SAMPLING

DURING 24H

STEAM EXPLOSION:

•3 kg per batch

•Pressure: 18 bars

•Retention time: 2

minutes

ENZYMATIC HYDROLYSIS:

•50g dry matter/ L citrate buffer pH 4.8

•6 FPU/ g DM Cellulase from Trichoderma

reseei (Celluclast; Novozyme ®)

•30 CBU/ g DM Cellobiohydrolase from

Aspergilllus niger (Novozyme 188,

Novozyme®)

GLUCOSE

QUANTIFICATION BY

HPAEC-PAD

HYDROLYSIS

KINETICS

0% 5% 10% 15% 20% 25% 0 500 1000 1500 Hyd rolysis % Time (minutes)

Miscanthus X giganteus

0% 10% 20% 30% 40% 50% 60% 70% 0 500 1000 1500 Hyd rolysis % Time (minutes)

Sugar Beet Pulp (SBP)

Raw C200 Steam exploded (SE)C200 _{Raw Miscanthus} _{SE Miscanthus}

Cellulose 51 % 58 % Hemicelluloses 31 % 12 % Lignins 23 % 25 % Raw SBP SE SBP Cellulose 21 % 54 % Hemicelluloses 23 % 13 %

Lignins undetermined undetermined

Raw Corn Straw SE Corn Straw

Cellulose 38 % 54 % Hemicelluloses 42 % 13 %

Lignins 16 % 18 %

Acknowledgment: authors are grateful for the financial support of the Walloon Region in the frame of the Lignofuel Program and the Technose program

Steam explosion pre-treatment  no positive effect on hydrolysis of pure cellulose.

Steam explosion pre-treatment  hemicellulose hydrolysis  increases cellulose accessibility

to enzyme  increases enzymatic hydrolysis

0% 5% 10% 15% 20% 25% 30% 35% 0 200 400 600 800 1000 1200 1400 Hyd rolysis % Time (minutes)