School of Resources and Environment, Anhui Agricultural University, Hefei, 230036, China.
School of Resources and Environment, Anhui Agricultural University, Hefei, 230036, China.
Chemosphere. 2022 Jun;296:133981. doi: 10.1016/j.chemosphere.2022.133981. Epub 2022 Feb 14.
Modification of pristine biochars has received increasing attentions due to the significant potential in enhancing adsorption performance. In this work, the co-modification of KOH and KMnO on biochar (K-Mn-BC) was performed, with the effect of KOH/KMnO modification on biochar properties and their adsorption toward tetracycline (TC) being extensively explored. Results showed that KOH/KMnO modification can significantly regulate biochars to form hierarchical structure. The obtained K-Mn-BC was characterized with a high specific surface area (1524.6 m g) and total pore volume (0.85 cm g). In addition, the K-Mn-BC exhibited a high adsorption capacity of 584.19 mg g toward TC at 318 K, and pseudo-second-order (R:0.993～0.998) and Langmuir (R: 0.834～0.874) models can fit well with the adsorption behavior. Moreover, the obtained K-Mn-BC can efficiently adsorb TC within a wide pH range (3.0-10.0), and were not affected by the co-existing ions. The possible mechanisms for the high adsorption capacity were ascribed to the pore filling and π-π interaction, following by hydrogen bonding and metal complexation. The obtained K-Mn-BC is a suitable adsorbent for TC removal from water due to the hierarchical structure, high adsorption capacity, and stable adsorption effect.
由于在提高吸附性能方面具有显著的潜力，原始生物炭的改性受到了越来越多的关注。本工作通过 KOH 和 KMnO 对生物炭（K-Mn-BC）进行共改性，广泛研究了 KOH/KMnO 改性对生物炭性质及其对四环素（TC）吸附性能的影响。结果表明，KOH/KMnO 改性可以显著调节生物炭形成分级结构。所制备的 K-Mn-BC 具有高比表面积（1524.6 m²/g）和总孔体积（0.85 cm³/g）。此外，K-Mn-BC 在 318 K 时对 TC 的吸附容量高达 584.19 mg/g，准二级（R²：0.993～0.998）和 Langmuir（R²：0.834～0.874）模型能够很好地拟合吸附行为。此外，所制备的 K-Mn-BC 能够在较宽的 pH 范围内（3.0-10.0）有效吸附 TC，且不受共存离子的影响。高吸附容量的可能机制归因于孔填充和π-π相互作用，随后是氢键和金属络合。由于具有分级结构、高吸附容量和稳定的吸附效果，所制备的 K-Mn-BC 是一种适合从水中去除 TC 的吸附剂。
