Abstract Tannin is often used as a heavy metal adsorption material, and the formation of complex between tannin and metal ion has a certain porous structure. Based on this, in this paper, wood fibers were used as the matrix to immobilize tannic acid, and then Fe (II) ions in aqueous solution were adsorbed in situ to modify some properties of wood fibers. The results showed that the higher the concentration of tannic acid, the more iron complexes immobilized on the wood fibers. These complexes could fill the pores of wood fibers, increase the specific surface area and enhance the moisture absorption. However, too many complexes could cluster, reducing the surface area. On the other hand, the complexes greatly reduced the number of hydroxyl groups on the fiber surface, making the surface hydrophobic. The complexes also could effectively reduce the pyrolysis temperature of wood fibers and increase the amount of residue char. Therefore, through such a simple two-step green treatment, it can not only remove some Fe (II) ions from water, but also modify the porosity, hydrophobicity and thermal stability of wood fibers.

中文翻译：

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基于单宁酸固定化和 Fe (II) 离子原位络合的木纤维功能化

摘要 单宁常被用作重金属吸附材料，单宁与金属离子形成的络合物具有一定的多孔结构。基于此，本文以木纤维为基体固定单宁酸，然后原位吸附水溶液中的Fe(II)离子对木纤维的某些性能进行改性。结果表明，单宁酸的浓度越高，固定在木纤维上的铁络合物越多。这些复合物可以填充木纤维的孔隙，增加比表面积，增强吸湿性。然而，太多的复合物可能会聚集，从而减少表面积。另一方面，配合物大大减少了纤维表面的羟基数量，使表面疏水。配合物还可以有效降低木纤维的热解温度，增加残炭量。因此，通过如此简单的两步绿化处理，不仅可以去除水中的部分Fe(II)离子，还可以改变木纤维的孔隙率、疏水性和热稳定性。