Tuesday, April 20, 2010
LL Conference Facility (Hilton Clearwater Beach)
Lignocellulosic biomass is the most abundant and attractive raw material as a resource for bioethanol production. However, it is difficult to decompose complex structure of lignocellulosic biomass for saccharification. Therefore, pretreatment is necessary. By increasing accessibility of cellulolytic enzyme to cellulose through the pretreatment, more effective enzymatic hydrolysis is possible.
Various pretreatments have been used to enhance the enzymatic hydrolysis. Biological pretreatment had advantages of mild conditions and low energy requirements. White-rot fungi are generally used in biological pretreatment because of their lignin degradability. However, the biological pretreatment doesn’t dramatically increase enzymatic hydrolysis in a short-term. Therefore, it is necessary to develop successive pretreatments such as short-term biological pretreatment followed by mild physical and organosolv pretreatments.
In this study, Liriodendron tulipifera as a material was used in chipped form. The chips were biologically degraded by white-rot fungi Cystidodontia isubellina, Stereum hirsutum, and Ceriporiopsis subvermispora. As a result, weight losses by C. isubellina, S. hirsutum, and C. subvermispora for 4 weeks were 8.77%, 6.07%, and 7.31%, respectively, and especially, holocellulose and lignin contents decreased 7.12% and 10.95% by C. isubellina, respectively. After that, the chips are ground for physical pretreatment, and then organosolv pretreatment is conducted using ethanol with dilute sulfuric acid as a catalyst. Sugar yield is evaluated through enzymatic hydrolysis, and ethanol yield is evaluated through SSF. To understand changes in the pretreated biomass during the successive pretreatments, physical properties, morphology and pore volume distribution are analyzed. From this study, the effectiveness of successive pretreatments will be investigated.
Various pretreatments have been used to enhance the enzymatic hydrolysis. Biological pretreatment had advantages of mild conditions and low energy requirements. White-rot fungi are generally used in biological pretreatment because of their lignin degradability. However, the biological pretreatment doesn’t dramatically increase enzymatic hydrolysis in a short-term. Therefore, it is necessary to develop successive pretreatments such as short-term biological pretreatment followed by mild physical and organosolv pretreatments.
In this study, Liriodendron tulipifera as a material was used in chipped form. The chips were biologically degraded by white-rot fungi Cystidodontia isubellina, Stereum hirsutum, and Ceriporiopsis subvermispora. As a result, weight losses by C. isubellina, S. hirsutum, and C. subvermispora for 4 weeks were 8.77%, 6.07%, and 7.31%, respectively, and especially, holocellulose and lignin contents decreased 7.12% and 10.95% by C. isubellina, respectively. After that, the chips are ground for physical pretreatment, and then organosolv pretreatment is conducted using ethanol with dilute sulfuric acid as a catalyst. Sugar yield is evaluated through enzymatic hydrolysis, and ethanol yield is evaluated through SSF. To understand changes in the pretreated biomass during the successive pretreatments, physical properties, morphology and pore volume distribution are analyzed. From this study, the effectiveness of successive pretreatments will be investigated.