Figure 4.

Reaction profiles for Kraft delignification of two native softwood biomass feedstocks: a) evolution of Spruce wood lignin into the liquor (green) as a function of cooking time and temperature, and; b) the quantification of β‐ethers in Pine wood lignin (quantified via analytical acidolysis), isolated from the liquor (light red) and residual lignin in the pulp (dark red), as a function of cooking time and temperature. For each graph, the programmed temperature (blue) increases steadily up to a fixed maximum of 170 °C.188, 190