In-situ immobilization of ZIF-67 on wood aerogel for effective removal of tetracycline from water
In-situ immobilization of ZIF-67 on wood aerogel for effective removal of tetracycline from water
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DOI：
10.1016/j.cej.2021.130184
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发表时间：
2021-05-13
影响因子：
15.1
通讯作者：
Huang, Dongmei
中科院分区：
文献类型：
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作者：
Chen, Guanyu;He, Song;Huang, Dongmei
金属-有机骨架材料在去除废水中的污染物方面得到了广泛的研究。然而，通常为粉末形式的M0 F遭受复杂的分离，这阻碍了它们的实际应用。本文中，通过将ZIF-67菱形十二面体原位锚定在通过从天然木材中选择性地去除木质素和半纤维素而获得的木材气凝胶上，成功地制备了复合吸附材料ZIF-67@WA（木材气凝胶）。具有层状结构的WA为ZIF-67提供了足够的附着位点，ZIF-67在复合材料中的含量达到32.65wt%。ZIF-67与1 μ m的晶粒尺寸保持其结晶度时，它被引入到WA的表面。考察了pH、接触时间、初始浓度、温度、共存离子和腐殖酸对四环素吸附的影响。该复合材料表现出优异的TC吸附容量（298 K时为273.84 mg.g（-1）），这与大多数先前报道的吸附剂相当。吸附过程符合准二级动力学模型和Langmuir等温模型。吸附热力学研究表明，吸附过程是自发的吸热过程。并提出了可能的吸附机理。经过3次循环后，TC去除率从94.09%下降到80.27%，表明该复合材料可以循环使用。测得钴的浸出量在允许范围内，表明在使用过程中不会造成严重的二次污染。上级吸附性能加上可压缩性、重量轻和易于分离，使ZIF-67@WA具有有效去除水中TC的潜力。
Metal-organic framework (MOF) materials have been extensively studied in the removal of pollutants in wastewater. However, MOFs, which are usually in powder form, suffer from complex separation that hinder their practical application. Herein, a composite adsorbent material, ZIF-67@WA (wood aerogel), has been successfully fabricated through in-situ anchoring of ZIF-67 rhombic dodecahedron on the wood aerogel obtained by selectively removing lignin and hemicellulose from natural wood. WA with lamellar structure provided sufficient attachment sites for ZIF-67, and the content of ZIF-67 in the composite reached 32.65 wt%. ZIF-67 with 1 mu m in grain size maintained its crystallinity when it was introduced to the surface of WA. The effects of pH, contact time, initial concentration, temperature, coexisting ions and humic acid on tetracycline (TC) adsorption were investigated. The composite showed excellent TC adsorption capacity (273.84 mg.g(-1) at 298 K), which was comparable to most previously reported adsorbents. Pseudo-second-order kinetic model and Langmuir isotherm model described the adsorption process well. Adsorption thermodynamic studies implied that the adsorption process was spontaneous and endothermic. Furthermore, the possible adsorption mechanism was proposed. The TC removal efficiency dropped from 94.09% to 80.27% after 3 cycles, revealing the composite could be recycled. The leaching of cobalt was measured to be within the permissible range, indicating that no serious secondary contamination would be caused during using the composite. The superior adsorption performance coupled with compressibility, light weight and facile separation gave ZIF-67@WA the potential to effectively remove TC from water.