Micro/nano-structural evolution in spruce wood during soda pulping

Abstract Alkaline delignification of wood tissue is the core global pulping technology and most prominent large-scale separation main components. This work aims at improved understanding interplay between topochemistry alkaline associated morphological changes. Morphology chemical structure partially soda-delignified chips were studied combining X-ray tomography (XRT), diffraction analysis compositional characterization (lignin carbohydrate content). The XRT studies wet samples (providing 3D structural information without interfering drying effects), allowed observation cell wall as an increasing amount lignin was removed with time. Comparison microstructure surface central parts treated showed a more delignified surface, which highlights dependence process on mass transport (hydroxide ions fragments) through tissue. crystallite size cellulose increased in <200> crystal planes during early stage while there little effect <110> plane.