Polypyrrole-Modified Nanocellulose Exhibits Superior Performance for Hg(II) Adsorption

Qizhong Xiong; Lei Zhang; Zijun Zhu; Gang Xu; Jianyuan Jing; Weifeng Zhang; Chaochun Zhang; Xinxin Ye

doi:10.3390/polym15122735

Polypyrrole-Modified Nanocellulose Exhibits Superior Performance for Hg(II) Adsorption

Polymers (Basel). 2023 Jun 19;15(12):2735. doi: 10.3390/polym15122735.

Authors

Qizhong Xiong^{1

2}, Lei Zhang^{1

2}, Zijun Zhu^{1

2}, Gang Xu^{1

2}, Jianyuan Jing^{1

2}, Weifeng Zhang¹, Chaochun Zhang¹, Xinxin Ye^{1

2}

Affiliations

¹ Anhui Province Key Lab of Farmland Ecological Conservation and Pollution Prevention, Anhui Province Engineering and Technology Research Center of Intelligent Manufacture and Efficient Utilization of Green Phosphorus Fertilizer, College of Resources and Environment, Anhui Agricultural University, Hefei 230036, China.
² Key Laboratory of JiangHuai Arable Land Resources Protection and Eco-Restoration, Ministry of Natural Resources, College of Resources and Environment, Anhui Agricultural University, Hefei 230036, China.

Abstract

Cellulose, a kind of polymer containing abundant functional groups, has widespread use in the adsorptive removal of environmental pollutants. An efficient and environmental friendly polypyrrole (PPy) coating approach is employed to modify the agricultural by-product straw derived cellulose nanocrystal (CNC) into excellent property adsorbents for removing the heavy metal ion of Hg(II). The FT-IR and SEM-EDS results demonstrated that PPy is formed on the surface of CNC. Consequently, the adsorption measurements proved that the obtained PPy-modified CNC (CNC@PPy) possesses a remarkably enhanced Hg(II) adsorption capacity of 1095 mg g^-1, owing to a plentiful functional group of doped Cl element on the surface of CNC@PPy by forming Hg₂Cl₂ precipitate. The results of the study suggest that the Freundlich model is more effective than the Langmuir model at describing the isotherms, while the pseudo-second order kinetic model is better suited to correlating with the experimental data compared to the pseudo-first order model. Further, the CNC@PPy exhibits an outstanding reusability, capable of maintaining 82.3% of its original Hg(II) adsorption capacity after five successive adsorption cycles. The findings of this work reveal a method to convert the agricultural by-product into high performance environmental remediation materials.

Keywords: CNC; CNC@PPy; Hg(II) adsorption; agricultural waste.

Grants and funding

This work was financially supported by the National Natural Science Foundation of China (Grant No. 22208003, G.X.), the Natural Science Foundation of Anhui Province (No. 1908085QC139, Q.X.), the Natural Science Foundation of Anhui Provincial Education Department (No. 2022AH050886, X.Y.), and the Major Science and Technology Project of Anhui province (No. 202103a06020012, C.Z.).