Comprehensive process for selectively separating lignocellulosic biomass into purified components with high yield

A comprehensive process for treating lignocellulosic biomass in order to separate the biomass into its component parts, the process comprising:

• a) contacting the lignocellulosic biomass with a first solvent for a period of time and at a first temperature at a severity in the range of about 2 to about 4 to remove extractive components and a portion of ash from the biomass;
• and
• b) separating the biomass from step (a) into a lignin product and a cellulose product by contacting the biomass from step (a) with a second solvent at a severity in the range of about 1.5 to 5 to provide a black liquor and a solid fraction containing cellulose.

A comprehensive process for treating lignocellulosic biomass in order to separate the biomass into its component parts, the process comprising:

• a) contacting the lignocellulosic biomass with a first solvent with or without a catalyst at a temperature at a severity in the range of about 1 to 5 to remove hemicelluloses and ash from the biomass;
• and
• b) separating the biomass from step (a) into a lignin product and a cellulose product by contacting the biomass from step (a) with a second solvent at a severity in the range of about 1.5 to 5 to provide a black liquor and a solid fraction containing cellulose.