Gao Jie, Li Zhenzhen, Wang Ziwen, Chen Tao, Hu Guowen, Zhao Yuan, Han Xiaobing
Hubei Key Laboratory of Radiation Chemistry and Functional Materials, School of Nuclear Technology and Chemistry & Biology, Hubei University of Science and Technology, Xianning 437100, China.
Gels. 2022 Aug 3;8(8):486. doi: 10.3390/gels8080486.
To meet the requirement of sustainable development, bio-based adsorbents were developed for the removal of dye contaminant. To improve the adsorption capacity of pure sodium alginate (SA) adsorbent for the removal of methylene blue (MB), aromatic bio-based tannin (Tan) was incorporated through the cross-linking with calcium ion. The obtained Tan/SA composite hydrogel beads were characterized with SEM, FTIR and TG, demonstrating that millimeter-sized beads were obtained through calcium cross-linking with enhanced thermal stability. The maximum capacity (247.2 mg/g) at optimal condition (pH = 12, T = 45 °C) was obtained for the 40%Tan/SA adsorbents, with a removal efficiency of 82.4%. This can be ascribed to the electrostatic attraction between SA and MB, as well as the formation of π-π stacking between Tan and MB. The adsorption process for MB is endothermic, and chemical adsorption, the removal efficiency was exceeded 90% after five cycles.
为满足可持续发展的要求，开发了用于去除染料污染物的生物基吸附剂。为提高纯海藻酸钠（SA）吸附剂对亚甲基蓝（MB）的吸附能力，通过与钙离子交联引入了芳香族生物基单宁（Tan）。对所得的Tan/SA复合水凝胶珠进行了扫描电子显微镜（SEM）、傅里叶变换红外光谱（FTIR）和热重分析（TG）表征，结果表明通过钙交联获得了毫米级的珠子，且热稳定性增强。40%Tan/SA吸附剂在最佳条件（pH = 12，T = 45 °C）下的最大吸附容量为247.2 mg/g，去除效率为82.4%。这可归因于SA与MB之间的静电吸引以及Tan与MB之间形成的π-π堆积。MB的吸附过程是吸热的，属于化学吸附，经过五个循环后去除效率超过90%。
