Tough carboxymethylcellulose nanofibers (CMF)/zirconium (Zr) hydrogels were easily obtained by a freeze-crosslinking method, where Zr-containing HCl solution was added to frozen CMF sol and the mixture was allowed to thaw. The Zr content of the hydrogels increased with increasing Zr concentration in the initial HCl solution. Furthermore, the mechanical strength increased with increasing Zr content. The Young's modulus value was improved by approximately 6 times compared to the CMF hydrogel without Zr, i.e., from 4.5 kPa to 27.2 kPa. The hydrogel had a porous structure with a pore size of 133 ± 37 μm and a CMF–Zr sheet structure around the pores. The obtained CMF–Zr hydrogel exhibited high adsorptivity for fluoride. The maximum adsorption capacity (Q_max) was estimated to be 24.1 mg g⁻¹. This simple gelation method provides useful insights for the development of easy-to-handle hydrogel-based adsorbents.

中文翻译：

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冷冻交联法制备氟化物吸附剂羧甲基纤维素纳米纤维/锆水凝胶

通过冷冻交联方法可以轻松获得坚韧的羧甲基纤维素纳米纤维 (CMF)/锆 (Zr) 水凝胶，其中将含 Zr 的 HCl 溶液添加到冷冻的 CMF 溶胶中，然后让混合物解冻。水凝胶的 Zr 含量随着初始 HCl 溶液中 Zr 浓度的增加而增加。此外，机械强度随着Zr含量的增加而增加。与不含Zr的CMF水凝胶相比，杨氏模量值提高了大约6倍，即从4.5kPa提高到27.2kPa。该水凝胶具有孔径为133±37μm的多孔结构和孔周围的CMF-Zr片状结构。所得CMF-Zr水凝胶对氟化物表现出高吸附性。最大吸附容量( Q _max )估计为24.1 mg g ^-1。这种简单的凝胶方法为开发易于处理的水凝胶吸附剂提供了有用的见解。