Abstract: Methods for obtaining purified lignin and the lignin that can be obtained by the methods are described. Methods include processing pretreated lignocellulosic biomass feedstock to recover the lignin and provide a lignin composition with a very low level of impurities such as metals and ash. In addition, the lignin recovered from the process can have a narrow molecular weight distribution and, depending upon the specific stages utilized in the process, can have a predetermined molecular weight. The process includes one or more separation stages in which a lignin-containing feedstock is mixed with a solvent solution. The mixture fractionates to form a solvent-rich liquid phase and a lignin-rich liquid phase, the lignin being partitioned across the phases according to the molecular weight of the lignin. Furthermore, the metal salts of the pretreated lignocellulosic biomass feedstock also partition across the phases.

Abstract: Methods for obtaining purified lignin and the lignin that can be obtained by the methods are described. Methods include processing pretreated lignocellulosic biomass feedstock to recover the lignin and provide a lignin composition with a very low level of impurities such as metals and ash. In addition, the lignin recovered from the process can have a narrow molecular weight distribution and, depending upon the specific stages utilized in the process, can have a predetermined molecular weight. The process includes one or more separation stages in which a lignin-containing feedstock is mixed with a solvent solution. The mixture fractionates to form a solvent-rich liquid phase and a lignin-rich liquid phase, the lignin being partitioned across the phases according to the molecular weight of the lignin. Furthermore, the metal salts of the pretreated lignocellulosic biomass feedstock also partition across the phases.

Abstract: There are provided processes for recovering a “heart-cut” liquid-lignin fraction from a lignin-containing stream such as a black liquor stream from a paper making process or the crude lignin stream within a non-destructive biomass conversion process by carbonating, acidifying and recovering the liquid-lignin fraction. The processes generally include reacting black liquor with a carefully selected amount of carbon dioxide (CO2), to decrementally reduce the pH of the black liquor and produce fractions of a dense liquid-lignin precipitate at each pH decrement to about a pH of 8. The sequential reduction in pH is less than or equal to about 1.5 in most embodiments, less than 1.0 in other embodiments, and less than 0.50 in still other embodiments. It has been discovered that lignin recovered from the dense liquid-lignin precipitate at the different pH decrements can have different molecular weight ranges and/or structures.

Abstract: Disclosed are processes for development and recovery of lipids from biomass. A plant or microorganism-based biomass can be developed to encourage a desired lipid profile. Following development, ecologically friendly normally gaseous fluids such as carbon dioxide can be pressurized to a supercritical state followed by rapid expansion. The fluid is first contacted with a biomass source including oil-containing microorganisms and/or agricultural products. For instance, fungi or algae can be bioconverted from another biomass sources such as canola seed or corn syrup and then contacted with the high pressure fluid. During a contact period, the fluid can diffuse into the biomass, and in particular through the cell walls of the biomass. The fluid undergoes rapid release of pressure and opens the cell structure for improved release of oil. The fluid can optionally be utilized for extraction following the explosion process. For instance, the fluid can be re-pressurized in the same vessel for extraction processes.

Abstract: A process for preparing cellulose acetate articles such as fibers. The process includes the following steps: Cellulose acetate is dissolved in a solvent to form a solution, the solvent made up of from 5% to 50% by weight of carbon dioxide and from 95% to 50% of a compatible solvent such as acetone. The solvent is above the supercritical conditions of CO.sub.2. The solution is filtrated of insoluble matter and extended to form a fiber or similar article.

Abstract: A process for producing increased concentrations of valuable neutrals such as sterols and tocopherols from fatty and/or resin acid-containing streams, such as tall oil and vegetable oil distillate, employs liquid water at elevated temperatures and pressures. The neutrals are concentrated by extracting fatty acids as well as resin acids of high purity. Temperature-dependent solubility differences allow for the further separation of resin acids from fatty acids.