From anthraquinone to teak wood quinones: Redox additive candidates for alkaline pulping
- 1Institute of Life and Environmental Sciences, University of Tsukuba, Tsukuba, 305-8572 Japan
Abstract
Alkaline pulping removes lignin while retaining the cellulose and hemicelluloses that determine pulp yield and quality. Anthraquinone (AQ) became an essential benchmark cooking additive because its quinone–hydroquinone redox cycle accelerates delignification while suppressing carbohydrate peeling. However, carcinogenicity concerns, regulatory pressure, and uncertainty regarding potentially hazardous impurities have restricted its continued use, particularly in safety-sensitive products. These concerns have renewed interest in redox-active alternatives, such as 2-methylanthraquinone (2-MAQ), 2-ethylanthraquinone (2-EAQ), and naturally occurring quinones. Teak ( Tectona grandis ) wood is a notable source of such compounds, containing 2-MAQ, deoxylapachol, lapachol, and related quinones. Studies indicate that teak extracts and purified teak quinones can enhance delignification or carbohydrate retention and, in some systems, lower the active alkali charge required to reach a target kappa number. Their natural origin, however, is not considered sufficient evidence that they are inherently “green.” This targeted narrative mini-review evaluates studies published between 1972 and 2026, using AQ as the historical and mechanistic reference for assessing these emerging additives. Current findings identify teak-derived quinones as promising candidates rather than direct replacements for AQ because their effectiveness varies with feedstock, cooking chemistry, additive dose, extraction method, composition, and purity. Further research should standardize extract composition, clarify the roles of individual quinones, and establish residual and migration behavior, toxicological safety, effects on pulp strength, and compatibility with mill chemical-recovery systems.
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BibTeX
@article{kong2026from,
title = {{From anthraquinone to teak wood quinones: Redox additive candidates for alkaline pulping}},
author = {Peifu Kong},
journal = {Journal of Bioresources and Bioproducts},
year = {2026},
month = oct,
doi = {10.1016/j.jobab.2026.100303},
url = {https://doi.org/10.1016/j.jobab.2026.100303},
note = {CC BY},
}
RIS
TY - JOUR
TI - From anthraquinone to teak wood quinones: Redox additive candidates for alkaline pulping
AU - Peifu Kong
PY - 2026
DA - 2026/10/25
JO - Journal of Bioresources and Bioproducts
DO - 10.1016/j.jobab.2026.100303
UR - https://doi.org/10.1016/j.jobab.2026.100303
AB - Alkaline pulping removes lignin while retaining the cellulose and hemicelluloses that determine pulp yield and quality. Anthraquinone (AQ) became an essential benchmark cooking additive because its quinone–hydroquinone redox cycle accelerates delignification while suppressing carbohydrate peeling. However, carcinogenicity concerns, regulatory pressure, and uncertainty regarding potentially hazardous impurities have restricted its continued use, particularly in safety-sensitive products. These concerns have renewed interest in redox-active alternatives, such as 2-methylanthraquinone (2-MAQ), 2-ethylanthraquinone (2-EAQ), and naturally occurring quinones. Teak ( Tectona grandis ) wood is a notable source of such compounds, containing 2-MAQ, deoxylapachol, lapachol, and related quinones. Studies indicate that teak extracts and purified teak quinones can enhance delignification or carbohydrate retention and, in some systems, lower the active alkali charge required to reach a target kappa number. Their natural origin, however, is not considered sufficient evidence that they are inherently “green.” This targeted narrative mini-review evaluates studies published between 1972 and 2026, using AQ as the historical and mechanistic reference for assessing these emerging additives. Current findings identify teak-derived quinones as promising candidates rather than direct replacements for AQ because their effectiveness varies with feedstock, cooking chemistry, additive dose, extraction method, composition, and purity. Further research should standardize extract composition, clarify the roles of individual quinones, and establish residual and migration behavior, toxicological safety, effects on pulp strength, and compatibility with mill chemical-recovery systems.
SN - 2369-9698
ER -