Institute of Advanced Materials, State Province Joint Engineering Laboratory of Zeolite Membrane Materials, College of Chemistry and Chemical Engineering, Jiangxi Normal University, Nanchang, 330022, China.
Institute of Advanced Materials, State Province Joint Engineering Laboratory of Zeolite Membrane Materials, College of Chemistry and Chemical Engineering, Jiangxi Normal University, Nanchang, 330022, China.
Environ Pollut. 2023 Apr 1;322:121200. doi: 10.1016/j.envpol.2023.121200. Epub 2023 Feb 7.
The alteration of agricultural wastes into novel adsorbents can stimulate their scalability in realistic application, showing great economic and environmental advantages. Here, we proposed a strategy to engineer rice husk (RH) with microporous melamine-formaldehyde networks (MFNs) resins and the utilization for dynamic removal of organic micropollutants rapidly and efficiently. was pre-treated to acquire attractive surface and unique hierarchical porosity, endowing with surface functionalization and essential filtering properties. MFNs can be uniformly generated in-situ on the fully exposed cellulose backbones of the pre-treated RH. MFNs granules functionalized RH (RH@MFNs) exhibited high removal efficiencies over 90% within 30 min for the adsorption of hazardous organic compounds (e.g., phenolic and antibiotic micropollutants) in static tests. Experiment results and density functional theory (DFT) simulation revealed that the synergy of hydrogen bonding, π-πinteraction, and micropore preservation dominates the adsorption. Further dynamic adsorption experiments showed that the removal efficiency and equilibrium removal capacity towards bisphenol A by RH@MFNs packed bed up-flow column were 2.6 and 67 times higher than that of raw RH, respectively. The column adsorption fits well with the Thomas model and bed depth service time (BDST) kinetic model. The inherent macropores inside RH and the roughness caused by the spiky structures and mesopores outside RH, as well as the accumulated MFNs granules, can lead to local turbulence of water flow around RH@MFNs, enabling fast and efficient adsorption. This sustainable and cost-effective preparation of RH-based adsorbents sheds light on the rational design of biomass waste adsorbents for realistic wastewater.
将农业废弃物改造成新型吸附剂可以刺激它们在实际应用中的可扩展性，具有巨大的经济和环境优势。在这里，我们提出了一种策略，即用微孔三聚氰胺-甲醛网络（MFN）树脂对稻壳（RH）进行工程化处理，并利用其快速高效地动态去除有机微量污染物。RH 经过预处理，获得了有吸引力的表面和独特的分级多孔性，赋予了表面功能化和必要的过滤性能。MFN 可以在预处理 RH 的完全暴露的纤维素骨架上均匀地原位生成。MFN 颗粒功能化 RH（RH@MFNs）在静态测试中对危险有机化合物（如酚类和抗生素微量污染物）的吸附，在 30 分钟内表现出超过 90%的去除效率。实验结果和密度泛函理论（DFT）模拟表明，氢键、π-π相互作用和微孔保持的协同作用主导了吸附。进一步的动态吸附实验表明，RH@MFNs 填充床上流柱对双酚 A 的去除效率和平衡去除容量分别比原始 RH 高 2.6 倍和 67 倍。柱吸附符合托马斯模型和床层深度服务时间（BDST）动力学模型。RH 内部的固有大孔和 RH 外部的刺状结构和中孔引起的粗糙度，以及积累的 MFN 颗粒，会导致 RH@MFNs 周围水流的局部湍流，从而实现快速高效的吸附。这种可持续且具有成本效益的 RH 基吸附剂的制备为实际废水的生物质废料吸附剂的合理设计提供了思路。
