Abstract: Disclosed herein are methods, systems, and compositions for the uniform pretreatment of biomass within seconds with low inhibitor formation. The pretreatment process is used to convert biomass to a fuel, sugars, or other useful chemicals by subjecting the feedstock to a rapid retention time under pressure and temperature and/or chemical reactant. The system includes at least one high pressure, steam impermiable plug and a continuously-operating valve discharge apparatus to discharge pretreated feedstock while maintaining uniform pressure on the pretreatment system.

Abstract: Provided are cost-effective methods and systems for producing a low molecular weight reactive lignin from a lignocellulosic biomass. The process is rapid and the reactive lignin is easily separated from carbohydrates and other components of the biomass at low cost. This clean lignin product has a very low molecular weight, good hydroxyl content, and low ash and sulfur, making it valuable to many applications.