Lignin is the second most abundant biomass component, and is the largest source of aromatics in nature. Kraft lignin is a by-product of the Kraft pulping, which is the predominant chemical process used by the pulp and paper industry. Kraft lignin is usually burned as a low-grade fuel in recovery boilers. Because of its availability in large quantities and its large aromaticity, Kraft lignin is consid-ered as a valuable biomass source for the potential production of renewable fuels and chemicals