Department of Chemistry, Mississippi State University, Starkville, MS, 39762, United States.
Department of Chemistry, Mississippi State University, Starkville, MS, 39762, United States.
Chemosphere. 2020 Nov;258:127336. doi: 10.1016/j.chemosphere.2020.127336. Epub 2020 Jun 11.
Modification of commercially available Douglas fir biochar (BC) by iron oxide nanoparticle precipitation from aqueous Fe/Fe salt solutions upon NaOH treatment generated a hybrid adsorbent (MBC) that removed three common emerging aqueous contaminants, a stimulant (caffeine) and two anti-inflammatory drugs (ibuprofen and acetylsalicylic acid) through batch sorption. FeO particles (12.3 ± 7.1 nm diameter fundamental particles with aggregates 1-17 μm diameter) dispersed on the biochar surface provided magnetization and created new adsorption sites for the contaminant uptake. These smaller quasi-spherical, octahedral FeO particles as well as the spindle-like FeO particles were observed with scanning electron microscopy (SEM) images of MBC, and the composition was confirmed by X-ray powder diffraction (XRD). Adsorption features were evaluated using Langmuir and Freundlich isotherm models. The Langmuir adsorption capacities on MBC at 35 °C have increased from 24.6 ± 0.4 to 75.1 ± 1.8 mg/g for caffeine, 17.5 ± 0.4 to 39.9 ± 1.2 mg/g for ibuprofen and 106.2 ± 2.8 to 149.9 ± 4.5 mg/g for acetylsalicylic acid after FeO modification. Fast adsorption resulted in equilibrium within 5 min. MBC has potential as a low cost, green adsorbent for pharmaceutical mitigation from water with high adsorption capacities and fast kinetics. The Douglas fir biochar is a byproduct waste from a syn-gas from wood production process covering its production costs.
通过在 NaOH 处理下用氧化铁纳米颗粒从水性 Fe/Fe 盐溶液中沉淀，对市售花旗松生物炭（BC）进行修饰，生成了一种混合吸附剂（MBC），通过批量吸附去除了三种常见的新兴水性污染物，一种兴奋剂（咖啡因）和两种抗炎药（布洛芬和乙酰水杨酸）。分散在生物炭表面的 FeO 颗粒（直径为 12.3±7.1nm 的基本颗粒，团聚体直径为 1-17μm）提供了磁化，并为污染物的吸收创造了新的吸附位点。这些更小的准球形、八面体 FeO 颗粒以及纺锤形 FeO 颗粒在 MBC 的扫描电子显微镜（SEM）图像中被观察到，其组成通过 X 射线粉末衍射（XRD）得到确认。通过 Langmuir 和 Freundlich 等温线模型评估了吸附特征。在 35°C 下，MBC 对咖啡因的 Langmuir 吸附容量从 24.6±0.4 增加到 75.1±1.8mg/g，对布洛芬的吸附容量从 17.5±0.4 增加到 39.9±1.2mg/g，对乙酰水杨酸的吸附容量从 106.2±2.8 增加到 149.9±4.5mg/g。快速吸附导致在 5 分钟内达到平衡。MBC 具有作为一种低成本、绿色吸附剂的潜力，可从水中去除药物，具有高吸附容量和快速动力学。花旗松生物炭是木质素合成气生产过程中的一种副产物废物，覆盖了其生产成本。
