Bioethanol Production from Lignocellulosic Biomass Requiring No Sulfuric Acid: Mechanochemical Pretreatment and Enzymic Saccharification

Abstract

Bioethanol has become an important product recently. Manufacture depends on sugar or starch, but such processes conflict with the requirements for food supply. Lignocellulose has high potential as feedstock for bioethanol, and has been the focus of much research and development. Sulfuric acid is generally used for saccharification or pretreatment of lignocellulose, but we have developed a saccharification process not requiring sulfuric acid, which is more environment friendly, combining mechanochemical pretreatment and enzymatic saccharification processes. We studied the process design, and presented the technical and economical portfolio. Based on this portfolio, we developed low energy mechanochemical treatment and low cost saccharification processes. The commercialization of our system is expected to begin soon.

Comparison of the enzymatic digestibility of physically and chemically pretreated selected line of diploid- Miscanthus sinensis Shiozuka and triploid- M. × giganteus

“…4). The on-site production or self-preparation of cellulases has been proposed as a cost-effective method (Fujimoto et al, 2008;Hideno et al, 2012). The glucose yields of Shiozuka and M×G obtained using the enzyme from a culture of T.…”

“…Without stabilizer, hydrogen peroxide is decomposed to highly reactive oxygen species (superoxide and hydroxyl radicals) as per the following equation (Gould 1984(Gould , 1985 Cellulases are key enzymes in the biorefinery process based on sugar platform. The costs of cellulases including the purchase cost of commercial cellulases or their production cost, contribute to a large proportion of the total costs of biorefinery process such as the bioethanol production (Fujimoto et al, 2008). On-site production of cellulases is considered to be a solution for reducing the cost of cellulases, including the purchase cost of and transportation costs for distribution (Fujimoto et al, 2008;Hideno et al, 2012).…”

“…The costs of cellulases including the purchase cost of commercial cellulases or their production cost, contribute to a large proportion of the total costs of biorefinery process such as the bioethanol production (Fujimoto et al, 2008). On-site production of cellulases is considered to be a solution for reducing the cost of cellulases, including the purchase cost of and transportation costs for distribution (Fujimoto et al, 2008;Hideno et al, 2012). Trichoderma reesei and its mutant strains have been widely investigated (Zhang et al, 2006) as promising hyper cellulase-producing fungi.…”

Biomass Pretreatment with Hydrothermal Explosion for Bioethanol Production

“…Fujimoto et al 13) reported that glucose yield was 77% and xylose yield 21% Sugar yield decreased with decreasing enzyme amount.…”

Chemical Analysis of Impurities in Diverse Bioethanol Samples

“…The upper 11 samples given in Table 2 are imported crude ethanol samples without azeotropic distillation, and a sample named Miyako is a crude ethanol sample just before membrane-dehydration in a pilot-scale ethanol plant 6) . The bottom four samples are second-generation biofuels produced in a bench-scale ethanol plant of AIST 7), 8) . The upper 13 samples were kindly provided by private companies.…”