Jiabo Wang, Hongxia Zhu, Yue Hu, Laigang Hu, Zeming Wei, Yan Ying Li, Xinglu Hu
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引用次数: 0
Abstract
The occurrence of excessive levels of bivalent plumbum (Pb(II)) in wastewater poses a notable threat to both human health and ecological safety. In this study, orthogonal experiments were conducted to prepare coprecipitation-modified biochar (C-BC) and impregnation pyrolysis-modified biochar (I-BC) via potassium permanganate (KMnO4) for removing Pb(II) from wastewater. Three types of modified biochars (BCs) (Mn-BCs) namely, C-BC400, I-BC400, and I-BC700, were selected as high-efficiency adsorbents on the basis of their high removal rates (87.2%, 88.0%, and 91.2%, respectively) for 400 mg/L Pb(II) solutions. The transmission electron microscopy (TEM) and scanning electron microscopy (SEM)‒energy-dispersive X-ray spectroscopy (EDS) analysis results indicated that Mn elements were distributed only on the outer surfaces of the C-BC400 particles but occurred on the outer surface and were stably embedded in the I-BC400 and I-BC700 particles. Compared with those of the pristine (BCs), the Pb(II) adsorption rates of C-BC400, I-BC400, and I-BC700 increased by factors of 3.75, 2.09, and 5.70, respectively. The Pb(II) adsorption capacities of C-BC400, I-BC400, and I-BC700 (182.28, 133.16, and 69.25 mg/g, respectively) were significantly greater than those of the pristine BCs produced at 400 °C (45.43 mg/g) and 700 °C (40.71 mg/g). The excellent adsorption ability of Mn-BCs for Pb(II) depends on various adsorption mechanisms, including complexation, electrostatic attraction, surface adsorption, and ion exchange. These results suggest that Mn-BCs exhibit high application potential in the remediation of Pb(II)-contaminated wastewater.
期刊介绍:
The Environmental Research journal presents a broad range of interdisciplinary research, focused on addressing worldwide environmental concerns and featuring innovative findings. Our publication strives to explore relevant anthropogenic issues across various environmental sectors, showcasing practical applications in real-life settings.