Cellulose for bioethanol production
A process to obtain glucose from a pretreated lignocellulosic biomass comprises providing a lignocellulosic biomass and contacting said lignocellulosic biomass to a modified Caro's acid composition for a period of time necessary to remove more than 98.5% of the lignin present in the lignocellulosic biomass and thus obtaining a solid stream and a liquid stream. The solid stream is exposed to an enzyme blend to produce a hydrolysate comprising sugars obtained from the hydrolysis of cellulose and hemicellulose. Optionally, the hydrolysate may be fermented to produce value-added products.
1 . A process to obtain a value-added product from a lignocellulosic biomass, said process comprising the steps of:
providing a lignocellulosic biomass
contacting said lignocellulosic biomass with a Caro's acid composition for a period of time necessary to remove more than 98.5% of the lignin present in said lignocellulosic biomass and thus obtaining a solid stream and a liquid stream,
exposing said solid stream to an enzyme blend to produce a hydrolysate comprising sugars obtained from the hydrolysis of cellulose and hemicellulose, and
fermenting said hydrolysate with a fermenting organism to produce a value-added product; and
wherein said process is carried out at a temperature of less than 50° C.
2 . The process according to claim 1 where the solid stream comprises less than 15% of hemicellulose.
3 . The process according to claim 1 where the solid stream has a kappa number of less than 10.
4 . The process according to claim 1 where said enzyme blend comprises of cellulases and hemicellulases.
5 . The process according to claim 1 where said enzyme blend comprises of at least one exo-glucanase, at least one endo-glucanase and at least one β-glucosidase.
6 . The process according to claim 1 where said value-added product is ethanol.
7 . The process according to claim 1 where the fermenting organism is a bacterium is selected from the group consisting of all species from the genera Clostridium, Lactobacillus, Zymomonas, Bacillus , and Escherichia.
8 . The process according to claim 1 where the fermenting organism is a yeast selected from the group consisting of all species from the genera Saccharomyces, Candida, Kloeckera, Hanseniaspora, Brettanomyces, Pichia, Pachysolen, Schizosaccharomyces, Zygosaccharomyces, Kluyveromyces, Torulaspora and Lanchacea.
9 . A process to hydrolyze cellulose into glucose, said process comprising the following steps:
providing a reaction vessel;
providing a cellulose source into said reaction vessel in an aqueous medium, wherein said source of cellulose has a content of hemicellulose of less than 5%, and a kappa number of less than 2;
exposing said cellulose source to an enzyme blend that is capable of converting said cellulose into glucose;
optionally, recovering the solution comprising glucose; and
wherein said process is carried out at a temperature of less than 50° C.
10 . The process according to claim 9 where said enzyme blend comprises of cellulases and hemicellulases.
11 . The process according to claim 9 where said enzyme blend comprises of at least one exo-glucanase, at least one endo-glucanase and at least one β-glucosidase.
12 . The process according to claim 9 wherein said cellulose source is exposed to an enzyme blend for a period of 1 to 168 hours.
13 . The process according to claim 9 further comprising a step of exposing the glucose containing solution to an organism capable of converting glucose to said value added product, wherein said organism is selected from the group consisting of bacterium or fungi, or any combination thereof.
14 . The process according to claim 13 where said value added product is ethanol.
15 . The process according to claim 13 where the bacterium is selected from the group consisting of all species from the genera Clostridium, Lactobacillus, Zymomonas, Bacillus , and Escherichia.
16 . The process according to claim 13 where the fungi is selected from the group consisting of all species from the genera Saccharomyces, Candida, Kloeckera, Hanseniaspora, Brettanomyces, Pichia, Pachysolen, Schizosaccharomyces, Zygosaccharomyces, Kluyveromyces, Torulaspora and Lanchacea.
17 . A process to convert cellulose into glucose, and optionally other value-added products, comprising the following steps:
providing a reaction vessel;
providing a cellulose source to said reaction vessel; wherein said source of cellulose having a content of hemicellulose of less than 5%, and a kappa number of less than 2;
exposing said cellulose source to an enzyme blend that is capable of converting said cellulose into glucose;
adding to said vessel an organism capable of converting the glucose into value-added products; and
wherein said process is carried out at a temperature of less than 50° C.
18 . The process according to claim 17 wherein said enzyme blend comprises of cellulases and hemicellulases.
19 . The process according to claim 17 wherein said enzyme blend comprises of at least one exo-glucanase, at least one endo-glucanase and at least one β-glucosidase.