College of Environmental Engineering, Wuhan Textile University, Wuhan, 430200, China; Clean Production of Textile Printing and DyeingEngineering Research Center, Ministry of Education, Wuhan, 430200, China.
College of Environmental Engineering, Wuhan Textile University, Wuhan, 430200, China.
Chemosphere. 2024 Apr;354:141739. doi: 10.1016/j.chemosphere.2024.141739. Epub 2024 Mar 17.
Considering the persistent and covert nature of heavy metal soil contamination, the sustainable development of ecological environments and food safety is at significant risk. Our study focuses on remediating soils contaminated with chromium (Cr); we introduce an advanced remediation material, iron oxide phosphoric acid-loaded activated biochar (HFBC), synthesized through pyrolysis. This HFBC displays greater microporosity, fewer impurities, and enhanced efficiency for the remediation process. Our research utilized a comprehensive set of analytical techniques, including Scanning Electron Microscopy (SEM), Fourier Transform Infrared Spectroscopy (FTIR), and X-ray Photoelectron Spectroscopy (XPS), alongside adsorption studies to elucidate the Cr removal mechanism. The effectiveness of HFBC in remediation was influenced by several factors: the pH level, dosage of HFBC, the initial concentration of Cr, and the ambient temperature. Our results indicated an optimal chromium (VI) adsorption capacity of 55.5 mg/g by HFBC at a pH of 6.0 and a temperature of 25 °C, with the process adhering to the pseudo-second-order kinetic model and the Langmuir adsorption isotherm, thus suggesting spontaneity in the uptake method. Moreover, this mechanism encompasses both adsorption and reduction reactions. Using HFBC in pot experiments with cabbage indicated not only an increase in soil pH and cation exchange capacity (CEC), but also a surge in bacterial community abundance. Significant reductions in bioavailable chromium were also recorded. Interestingly, HFBC addition bolstered the growth of cabbage, while concurrently diminishing chromium accumulation within the plant, particularly notable as the HFBC application rate increased. In summation, the HFBC produced in our study has demonstrated convincing efficacy in removing chromium from aqueous solutions and soil. Moreover, the positive agronomic implications of its use, such as enhanced plant growth and reduced heavy metal uptake by plants, indicate its high potential for operational value in the domain of environmental remediation of heavy metals.
考虑到重金属土壤污染的持久性和隐蔽性，生态环境和食品安全的可持续发展面临着重大风险。我们的研究重点是修复铬（Cr）污染的土壤；我们引入了一种先进的修复材料，即氧化铁磷酸负载的活性生物炭（HFBC），通过热解合成。这种 HFBC 具有更大的微孔体积、更少的杂质和增强的修复效率。我们的研究利用了一系列全面的分析技术，包括扫描电子显微镜（SEM）、傅里叶变换红外光谱（FTIR）和 X 射线光电子能谱（XPS），以及吸附研究，以阐明 Cr 去除机制。HFBC 在修复中的有效性受到多种因素的影响：pH 值、HFBC 的用量、Cr 的初始浓度和环境温度。我们的结果表明，在 pH 值为 6.0 和温度为 25°C 的条件下，HFBC 的最佳六价铬（Cr(VI)）吸附容量为 55.5mg/g，该过程符合准二级动力学模型和 Langmuir 吸附等温线，这表明该方法具有自发性。此外，这种机制包括吸附和还原反应。在白菜的盆栽实验中使用 HFBC 不仅增加了土壤的 pH 值和阳离子交换容量（CEC），还增加了细菌群落的丰度。生物可利用的铬也显著减少。有趣的是，HFBC 的添加不仅促进了白菜的生长，同时还减少了植物体内铬的积累，尤其是随着 HFBC 施用量的增加，这种效果更加明显。总之，我们研究中制备的 HFBC 在去除水溶液和土壤中的铬方面表现出令人信服的效果。此外，其使用的积极农艺意义，如促进植物生长和减少植物对重金属的吸收，表明其在重金属环境修复领域具有很高的应用价值。
