. 2023 Feb 6;24(3):1065–1077. doi: 10.1021/acs.biomac.2c01385

Table 1. Overview of Technical Lignin Extraction Processes, And Solubility, Weight-Average Molecular Weight (M_w), Dispersity (Đ), and Impurities in the Different Types of Lignins.

lignin type	extraction process^18,19	solubility^20,21	M_w (kDa)^20,21	Đ^21,22	impurities²⁰
kraft lignin	170 °C, NaOH, Na₂S	aqueous media pH > 10	0.1–3	2.5–3.5	sulfur
lignosulfonates	140 °C, SO₂, Na⁺/Ca⁺/Mg⁺/NH₄⁺	water	20–50	6.0–8.0	sulfur
organosolv lignin	150–200 °C, acetic acid/formic acid/organic solvents	organic solvents	0.5–4	1.3–4.0	carbohydrates and ash
soda lignin	150–170 °C, NaOH	aqueous media pH > 10	0.8–3	2.5–3.5	carbohydrates and ash

Table 1. Overview of Technical Lignin Extraction Processes, And Solubility, Weight-Average Molecular Weight (Mw), Dispersity (Đ), and Impurities in the Different Types of Lignins.