Wood extractives

Ongoing research projects

Understanding the Role of Wood Extractives in Formation of Pitch Deposits (WEPitch)
Control of wood extractives has a vital role in closing the water loops in pulp mills, thus helping the pulp and paper industry to achieve the “zero effluent” target. As there is no efficient way to control and remove them from the fiber line, extractives can be a technical challenge. Wood extractives cause a lot of effort to the process and can create serious problems, because they flow and accumulate in water, forming pitch deposits. The extractives retained in the pulps may adversely affect the physiochemical properties of the products. Efficient removal of pitch deposits from the fiber line is currently hampered by the lack of knowledge of their full chemical characteristics and the exact formation mechanism. The Industry- and FinnCERES- jointly funded project WEPitch (2024-2028) is designed to find ways to gain essential knowledge to understand, prevent and control deposit formation and improve the overall operation, revenue and quality performance of the pulp and paper mill.

Related publication:
Dou, J.*; Niemelä, Klaus*; Haatainen, Tiina; Tervola, Pekka; Vehmaa Janne*. Investigation of pitch deposits throughout the fibre line of softwood pulp mills. (2023-03-28) J. Cleaner Prod. 405, 136940. https://doi.org/10.1016/j.jclepro.2023.136940.

Stability enhancement of softwood (sawdust wood and bark) stilbene through chemical functionalization as ultra stable UV-filters in sunscreen (FACE+)

Trans-stilbenes can be isomerized to their cis-isomers under sunlight, and the cis-isomers are prone to undergo a Mallory reaction yielding polycyclic aromatic hydrocarbons. This preference is very hard to overcome as it is strictly under orbital symmetry control. The Academy of Finland Research Fellow project (2023–2027) will focus on functionalizing the recovered stilbene from pine wood sawdust and spruce bark as ultra-stable UV-filter alternatives for sunscreen. This may improve the stilbene stability 1000-fold without losing its UV-absorbing activity. These materials are today merely burned for energy, but when using them to added-value chemicals, it could allow more incomes for the Finnish forest owners and industry.

Related publications:

Dou, J.*; Multia, Evgen; Dong, Xinyue; Wang, Lei*; Vuorinen, Tapani. Valorization of long-neglected spruce bark and bark-press effluents through integrated utilization of stilbenoids and pectin. (2023) Chem. Eng. J. https://doi.org/10.1016/j.cej.2023.144122.

Dou, J.*; Sui, M.; Malinen, K.; Pesonen, T.; Isohanni, T.; Vuorinen, T. Spruce Bark Stilbenes as a Nature-inspired Sun Blocker for Sunscreens. (2022-03-02) Green Chem. 24, 2962−2974. https://doi.org/10.1039/D2GC00287F.

Research Council of Finland Fellow Dr. Jinze Dou

Dr. Dou obtained his PhD in the field of Bioproduct Technology under the supervision of Prof. Tapani Vuorinen from Aalto University in 2018, though part of his research was carried out at the University of Wisconsin Madison, USA, under the supervision of Prof. John Ralph. During his postdoctoral research work at Aalto, he had long visits to the University of Aveiro, Portugal (Prof. Dmitry Evtyuguin), Lappeenranta-Lahti University of Technology in Finland (Prof. Tuomo Sainio) and Shandong University, China (Prof. Jian Zhao). In addition to these academic steps, he also has industrial experience working as a research scientist at Andritz Oy (January 2022-August 2023). The Research Council of Finland (formerly known as the Academy of Finland) awarded Dou the Academy Research Fellowship for 2023-2027.

Research Assistant (preparing for doctoral thesis work) Wajeeha Munib

Munib is a doctoral student specializing in the stability enhancement of stilbenes from pine wood sawdust and spruce bark through chemical functionalization. She has a foundational Master's degree in organic chemistry and a robust research background in organic synthesis. Her current doctoral research is focused on developing ultra-stable UV filters for sunscreen applications, leveraging the inherent properties of softwood sawdust and spruce bark extractive stilbenes. Areas of interest include: wood extractives, controlled stereo chemical reactions, and chemical functionalization of stilbenes for macrocyclization. 

Research Assistant Hao Xi

Hao is an aspiring master’s student at Aalto University, focusing on biomass refining. His academic journey is enriched by practical experiences, such as internships at Metsä Board in 2021 and BASF in 2023. An academic exchange at the Technical University of Denmark broadened his horizons. Currently, he is advancing his Master’s thesis under the guidance of Dr. Jinze Dou. With a passion for sustainability, Hao’s goal is to apply his knowledge to initiatives that have a significant and positive environmental impact.

Master's thesis worker Muhammad Ali

Ali contributes as a Master's thesis worker on the characterization of extractive-free de-inked pulp. His focus is to integrate the surface chemistry and full chemistry data of de-inked pulp. The work will offer a holistic understanding of the chemical characteristics of extractive-free de-inked pulp.