Fast Track to Molar‐Mass Distributions of Technical Lignins

Abstract

Abstract Technical lignins (waste products obtained from wood pulping or biorefinery processes) have so far required lengthy analysis procedures and different eluents for molar‐mass analysis by gel permeation chromatography (GPC). This challenge has become more pressing recently since attempts to utilize lignins have increased, leading to skyrocketing numbers of samples to be analyzed. A new approach, which uses the eluent DMSO/LiBr (0.5 % w / v ) and converts lignosulfonate salts into their acidic form before analysis, overcomes these limitations by enabling measurement of all kinds of lignins (kraft, organosolv, soda, lignosulfonates) in the same size‐exclusion chromatography (SEC) system without the necessity of prior time‐consuming derivatization steps. In combination with ultra‐performance liquid chromatography (UPLC), analysis times are shortened to one tenth of classical lignin GPC. The new approach is presented, along with a comparison of GPC and UPLC methods and a critical discussion of the analytical parameters.