Xiong Qizhong, Zhang Lei, Zhu Zijun, Xu Gang, Jing Jianyuan, Zhang Weifeng, Zhang Chaochun, Ye Xinxin
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.
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.
Polymers (Basel). 2023 Jun 19;15(12):2735. doi: 10.3390/polym15122735.
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, owing to a plentiful functional group of doped Cl element on the surface of CNC@PPy by forming HgCl 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.
纤维素是一种含有丰富官能团的聚合物，在吸附去除环境污染物方面有广泛应用。采用一种高效且环保的聚吡咯（PPy）包覆方法，将农业副产品秸秆衍生的纤维素纳米晶（CNC）改性为具有优异性能的吸附剂，用于去除汞（II）重金属离子。傅里叶变换红外光谱（FT-IR）和扫描电子显微镜-能谱（SEM-EDS）结果表明，PPy形成于CNC表面。因此，吸附测量证明，所得的PPy改性CNC（CNC@PPy）具有显著增强的汞（II）吸附容量，为1095 mg/g，这归因于通过形成HgCl沉淀，CNC@PPy表面存在大量掺杂的Cl元素官能团。研究结果表明，在描述等温线方面，Freundlich模型比Langmuir模型更有效，而与一级动力学模型相比，准二级动力学模型更适合与实验数据相关联。此外，CNC@PPy表现出出色的可重复使用性，在连续五次吸附循环后，仍能保持其原始汞（II）吸附容量的82.3%。这项工作的研究结果揭示了一种将农业副产品转化为高性能环境修复材料的方法。
