Separation of lignin from hydrolyzate
AssigneeAPI Intellectual Property Holdings, LLC
InventorsTheodora Retsina, Vesa Pylkkanen
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Abstract
A method for the production water insoluble reactive lignin having low sulfur content and lignosulfonates from lignocellulosic material in a batch or continuous process. Lignocellulosic material is fractionated to produce water insoluble native lignin and lignosulfonates in various ratios, while preserving the cellulose and hydrolyzed hemicelluloses using water, ethanol and sulfur dioxide.
Claims22
A process for producing lignin and lignosulfonates by fractionating lignocellulosic material into lignin, cellulose and hydrolyzed hemicelluloses through a staged treatment of the lignocellulosic material with a solution of aliphatic alcohol, water and sulfur dioxide with intermediate removal and preservation of lignin.
A process for producing lignin and lignosulfonates from the hemicelluloses of a lignocellulosic material by fractionating lignocellulosic material into lignin, cellulose and hydrolyzed hemicelluloses through a staged treatment of the lignocellulosic material with a solution of aliphatic alcohol, water and sulfur dioxide, most preferably containing 40% to 60% water, with intermediate removal and preservation of cellulose and lignin, and a sulfur dioxide charge of 0% to 5% or more is used in one or more subsequent stages of treatment with intermediate removal and preservation of lignin and cellulose.
A process for producing monomer sugars from the hemicelluloses of a lignocellulosic material by fractionating lignocellulosic material into lignin, cellulose and hydrolyzed hemicelluloses through a staged treatment of the lignocellulosic material with a solution of aliphatic alcohol, water and sulfur dioxide, most preferably containing 40% to 60% water, with intermediate removal and preservation of cellulose, the first stage using a 0.05% to 9% sulfur dioxide solution and subsequent stage(s) using a 5% to 30% or more sulfur dioxide solution.
A process for producing native lignin and lignosulfonates by fractionating lignocellulosic material into lignin, cellulose and hydrolyzed hemicelluloses through a staged treatment of the lignocellulosic material with a solution of aliphatic alcohol, water and sulfur dioxide comprising the steps of:
- Cooking under acidic conditions to produce hydrolyzed hemicelluloses, cellulose, and lignin and sulfonated lignin;
- Washing to separate lignin and hemicelluloses from cellulose in several stages to recover more than 95% of the aliphatic alcohol mixed with the cellulose;
- Evaporation to remove and recover cooking chemicals, remove side products;
- Heating of post evaporation hydrolyzate to precipitate lignin and maximize the hydrolysis of hemicelluloses;
- Lignosulfonate separation to remove lignosulfonates from hydrolyzate;
- Fermentation and distillation to produce and concentrate alcohols or organic acids;
- and
- Fractionation and/or separation to remove and recover side products.
Dependencies are inferred from the claim text.