Pretreatment process for conversion of cellulose to fuel ethanol

A process for converting a lignocellulosic feedstock to ethanol, the process consisting essentially of the following steps:

• a. Choosing a selectively bred feedstock, comprised of at least hemicellulose and cellulose on the basis of an increased ratio of arabinan plus xylan to total nonstarch polysaccharides (AX/NSP) over a starting feedstock material, wherein the feedstock is corn, oats, wheat, sugar cane, or a component thereof, and wherein the feedstock contains less than 10% starch;
• and
• b. Reacting the selectively bred feedstock at conditions which disrupt its fiber structure and effect an hydrolysis of a portion of the hemicellulose and cellulose, in order to create a pretreated feedstock with increased accessibility to being digested, during a treatment with cellulase enzymes;
• and
• c. Hydrolyzing the pretreated feedstock to sugars by using cellulase enzymes;
• and
• d. Fermenting the resulting sugars to ethanol;
• and
• e. Recovering the ethanol.

A process for converting a lignocellulosic feedstock to ethanol, the process consisting essentially of the following steps:

• a. Choosing a selectively bred feedstock, comprised of at least hemicellulose and cellulose, on the basis of an increased ratio of arabinan plus xylan to total nonstarch polysaccharides (AX/NSP) over a starting feedstock material, wherein the feedstock is a C4 perennial grass;
• and
• b. Reacting the selectively bred feedstock at conditions which disrupt its fiber structure and effect an hydrolysis of a portion of the hemicellulose and cellulose, in order to create a pretreated feedstock with increased accessibility to being digested, during a treatment with cellulase enzymes;
• and
• c. Hydrolyzing the pretreated feedstock to sugars by using cellulase enzymes;
• and
• d. Fermenting the resulting sugars to ethanol;
• and
• e. Recovering the ethanol.

A process for converting a lignocellulosic feedstock to glucose, consisting essentially of the following steps:

• a. Choosing a selectively bred feedstock, comprised of at least hemicellulose and cellulose, on the basis of an increased ratio of arabinan plus xylan to total nonstarch polysaccharides (AX/NSP) over a starting feedstock material, wherein the feedstock consists of corn, wheat, oats, sugar cane, or a component thereof, and wherein the feedstock contains less than 10% starch;
• and
• b. Reacting the selectively bred feedstock to conditions which disrupt its fiber structure and effect an hydrolysis of a portion of the hemicellulose and cellulose, in order to create a pretreated feedstock with increased accessibility to being digested, during a treatment with cellulase enzymes;
• and
• c. Hydrolyzing at least 40% of the cellulose in the pretreated feedstock to glucose by using cellulase enzymes.

A process for converting a lignocellulosic feedstock to glucose, consisting essentially of the following steps:

• a. Choosing a selectively bred feedstock, comprised of at least hemicellulose and cellulose, on the basis of an increased ratio of arabinan plus xylan to total nonstarch polysaccharides (AX/NSP) over a starting feedstock material, wherein the feedstock consists of a C4 perennial grass;
• and
• b. Reacting the selectively bred feedstock to conditions which disrupt its fiber structure and effect an hydrolysis of a portion of the hemicellulose and cellulose, in order to create a pretreated feedstock with increased accessibility to being digested, during a treatment with cellulase enzymes;
• and
• c. Hydrolyzing at least 40% of the cellulose in the pretreated feedstock to glucose by using cellulase enzymes.

A process for converting a lignocellulosic feedstock to ethanol, the process consisting essentially of the following steps:

• a. Choosing a feedstock, comprised of at least hemicellulose and cellulose, and characterized by a ratio of arabinan plus xylan to total nonstarch polysaccharides (AX/NSP) of greater than 0.39, wherein the feedstock is not corn fiber;
• and
• b. Reacting the feedstock at conditions which disrupt its fiber structure and effect an hydrolysis of a portion of the hemicellulose and cellulose, in order to create a pretreated feedstock with increased accessibility to being digested, during a treatment with cellulase enzymes;
• and
• c. Hydrolyzing the pretreated feedstock to sugars by using cellulase enzymes;
• and
• d. Fermenting the resulting sugars to ethanol;
• and
• e. Recovering the ethanol.

A process for converting a lignocellulosic feedstock to glucose, consisting essentially of the following steps:

• a. Choosing a feedstock, comprised of at least hemicellulose and cellulose, characterized by a ratio of arabinan plus xylan to total nonstarch polysaccharides (AX/NSP) of greater than 0.39, wherein the feedstock is not corn fiber;
• and
• b. Reacting the feedstock at conditions which disrupt its fiber structure and effect an hydrolysis of a portion of the hemicellulose and cellulose, in order to create a pretreated feedstock with increased accessibility to being digested, during a treatment with cellulase enzymes;
• and
• c. Hydrolyzing at least 40% of the cellulose in the pretreated feedstock to glucose by using cellulase enzymes.