(139b) Multicycle 1,4-Butanediol Delignification of Ponderosa Pine

This study investigates the organosolv delignification of Ponderosa pine residues, collected from forest restoration initiatives in the western United States, using an aqueous 70% 1,4-butanediol under autocatalytic conditions. After the initial treatment, BDO was regenerated via membrane separation of the spent liquor, following acidification and lignin isolation, enabling its reuse in subsequent delignification cycles. Over four consecutive cycles, we conducted comprehensive analyses of both the recovered lignin and the resultant pulp using established analytical and spectral techniques to assess the impact of stepwise BDO regeneration on product quality. In addition, we evaluated the stability of BDO throughout the process. Our findings demonstrate that biorenewable, high-boiling point BDO can effectively delignify softwoods, yielding pulp suitable for various applications, such as dissolving pulp and cellulose nanomaterials, as well as lignin with high-value potential.

Keywords – Ponderosa pine, 1,4 butanediol delignification, multicycle, lignin, pulp