Lignin is a complex phenolic polymer found in biomass feedstocks and biomass derived products. This procedure describes the isolation of lignin from an acidic solution, and measurement of a maximum peak and absorptivity constant specific to that sample or biomass type. These values can usually be applied to other samples of the same matrix. Ultraviolet-Visible spectroscopy (UV-Vis) is employed in this technique, and measurements are made at a peak maxima that minimizes the confounding influence of other analytes.
