Phenolation of Kraft Lignin under Acidic Conditions for Potential AdhesiveApplications

摘要

Lignin is the most abundant aromatic natural polymer on earth. Approximately 50 million metric tons of lignin is produced annually as a byproduct of pulp and paper industry. The vast majority of technical lignin produced is kraft lignin. However, up until 2011, only 60,000 tons were produced annually for commercial application. Recently, a pulp mill in North Carolina installed the LignoBoost Process and thereby increases the commercial availability of kraft lignin by an additional 20,000 tons. Thus,almost all kraft lignin are currently burned to generate energy and recover cooking chemicals, which is a necessity to render the kraft process economically viable. Nevertheless, about 10-15% of lignin can be extracted without adversely affect the chemical recovery process. The fuel value of kraft lignin in black liquor is currently about $100 per ton. If high value products can be derived from kraft lignin, potentially 5-7.5 million tons could be available from the pulp and paper industry.