PROCESS FOR THE ISOLATION OF LIGNIN FROM BLACK LIQUOR AND MODIFICATION OF THE LIGNIN FOR PLASTIC APPLICATIONS

摘要

A process for the isolation of lignin from black liquor and modification of lignin for use in many plastic applications is disclosed. The isolation of lignin consists of removing all of the non-lignin components from black liquor solution. The non-lignin components including but not limited to organic acids, sugars, and inorganic materials can be removed using either solvent extraction or ion-exchange resin or a combination of both methods. The isolated lignin is water soluble. The non-lignin components can be further isolated and sold or reused in the pulping or lignin isolation processes. The isolated lignin can be further modified in order to meet the needs of the desired plastic application.

主权项

1. A process for isolating lignin from an aqueous solution containing lignin and non-lignin components, where the process does not reduce the pH of the aqueous solution of lignin, the process comprising the steps of:
adding solvent to said aqueous solution forming a solvent and aqueous solution mixture; filtering said solution where lignin will be retained by the filter and the mixture containing the non-lignin component solution and solvent will permeate the filter; mixing retained lignin with water and repeating said step of adding solvent and said step of filtering said solution until said lignin is isolated from non-lignin components; and, removing excess water using vacuum distillation, falling film evaporation, rotary evaporation, reverse osmosis, or oven drying.