Patent ID: 6908995

Claim:
The process for production of the compounds, lignin, lignin-cellulose resinous compounds, carbon dioxide, and carbohydrates produced from biomass by the process consisting of mixing, heating, and reacting die components by the following steps: (1) preparation of biomass: excess water is removed from the biomass and ground or chipped into small pieces and utilized in the amount of 100 parts by weight; (2) adding aqueous alkali metal hydroxide: aqueous solution of alkali metal hydroxide containing 25 to 50 parts by weight of alkali metal hydroxide is added and mixed with the biomass; (3) converting biomass: the biomass is heated to about 140° C. to evaporate the water and break the Lignin-cellulose bond then heating is continued while agitating and the biomass becomes a thick paste; (4) dissolving converted biomass: water in the amount of 200 to 400 parts by weight is added and mixed with the convened biomass thereby dissolving most of the converted biomass, then filtered or decanted off the non-water soluble biomass; (5) adjusting the pH: an acidic salt forming compound, carbon dioxide, is added to the aqueous converted biomass solution until the pH is 3-7; (6) separating the components: the lignin-cellulose resinous products are skimmed from the top of the aqueous solution then the aqueous solution containing the carbohydrates and salt is filtered or decanted off the precipitated lignin; (7) crystalizing carbohydrates: the aqueous carbohydrates and salt solution is heated to evaporate water to concentrate the solution, then the carbohydrates are precipitated out, and the aqueous salt solution is filtered or decanted off; (8) recausticing: the aqueous solution containing salts is heated to evaporate excess water then placed in a furnace, with or without lignin, burned to remove organic material, then added to water, filtered, then reacted with an alkaline earth metal oxide, to produce alkali metal hydroxide for reuse and alkaline earth metal salt which precipitates; (9) alkaline earth metal oxide recovery: the alkaline earth metal salt is heated in a lime kiln to produce alkaline earth metal oxide and carbon dioxide fur reuse.