Preparation and properties of lignin-based composite membranes

ABSTRACT

Composite membranes were prepared from lignin alkali (LA), polyvinyl alcohol (PVA), and cellulose nanofibrils (CNF) using a simple, low-cost, and environmentally friendly method. The deodorization performances and structures of these membranes were also characterized. The sample referred to as L3C3P5 prepared with a solution containing 35.7 wt% LA, 53.6 wt% PVA, and 10.7 wt% CNF showed the best deodorization properties, and the H₂S adsorption time reached 36 min. The adsorption performance was further improved by adding nano-CuO to the membrane, and the H₂S adsorption time of the doped membrane L3C3P5C4 reached 60 min. While the H₂S adsorption performance improved, structural analysis revealed that the addition of nano-CuO reduced the crystallinity in the membrane, caused the membrane to crack, and led to a decrease in the mechanical properties. The surface oxygens in the L3C3P5C4 membrane were primarily C–O bonds and lattice oxygens in CuO. After the H₂S adsorption reaction, the lattice oxygen disappeared, and CuS products appeared.

GRAPHICAL ABSTRACT

KEYWORDS:

• Deodorization
• membrane
• lignin alkali
• H₂S
• PVA

Acknowledgments

The authors are very grateful to the editor and anonymous reviewers for their valuable comments and helpful suggestions.

Author contribution

Menglong Zheng implemented the research process and organized papers. Peng Lu revised the paper. Fen Li proposed research topics and conducted final review of the paper. Youjing Li sorted out the article data. Yanping Zhang revised the paper. Hong Yan and Jinghao Dong conducted review of the paper. All authors read and approved the final manuscript.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Data availability

The datasets used and/or analyzed during the cur-rent study are available from the corresponding author on reasonable request.

Additional information

Funding

This work was supported by the National Natural Science Foundation of China Fund [grant number 22278100], the Guangdong Province Engineering Laboratory for Air Pollution Control Open-end Fund [grant number 20193236-09-05] and the Natural Science Foundation of Heilongjiang Province [grant number E2018043].