香蕉秸秆生物炭吸附去除 Zn(II)、Mn(II)和 Cu(II)：吸附过程与机制。
Removal of Zn(II), Mn(II) and Cu(II) by adsorption onto banana stalk biochar: adsorption process and mechanisms.
机构信息
Key Laboratory of Ecology of Rare and Endangered Species and Environmental Protection, Guangxi Normal University, Guilin 541004, China and College of Environment and Resources, Guangxi Normal University, Guilin 541004, China E-mail:
School of Chemistry and Pharmaceutical Science, Guangxi Normal University, Guilin 541004, China.
出版信息
Water Sci Technol. 2020 Dec;82(12):2962-2974. doi: 10.2166/wst.2020.543.
Low-cost banana stalk (Musa nana Lour.) biochar was prepared using oxygen-limited pyrolysis (at 500 °C and used), to remove heavy metal ions (including Zn(II), Mn(II) and Cu(II)) from aqueous solution. Adsorption experiments showed that the initial solution pH affected the ability of the biochar to adsorb heavy metal ions in single- and polymetal systems. Compared to Mn(II) and Zn(II), the biochar exhibited highly selective Cu(II) adsorption. The adsorption kinetics of all three metal ions followed the pseudo-second-order kinetic equation. The isotherm data demonstrated the Langmuir model fit for Zn(II), Mn(II) and Cu(II). The results showed that the chemical adsorption of single molecules was the main heavy metal removal mechanism. The maximum adsorption capacities (mg·g) were ranked as Cu(II) (134.88) > Mn(II) (109.10) > Zn(II) (108.10)) by the single-metal adsorption isotherms at 298 K. Moreover, characterization analysis was performed using Fourier transform infrared spectroscopy, the Brunauer-Emmett-Teller method, scanning electron microscopy with energy-dispersive X-ray spectroscopy, X-ray diffraction, and X-ray photoelectron spectroscopy. The results revealed that ion exchange was likely crucial in Mn(II) and Zn(II) removal, while C-O, O-H and C = O possibly were key to Cu(II) removal by complexing or other reactions.
采用限氧热解（在 500°C 下进行）制备了低成本的香蕉茎（Musa nana Lour.）生物炭，用于从水溶液中去除重金属离子（包括 Zn(II)、Mn(II)和 Cu(II)）。吸附实验表明，初始溶液 pH 值影响生物炭在单金属和多金属体系中吸附重金属离子的能力。与 Mn(II)和 Zn(II)相比，生物炭对 Cu(II)表现出高度选择性的吸附。所有三种金属离子的吸附动力学均遵循拟二级动力学方程。等温线数据表明，Langmuir 模型适用于 Zn(II)、Mn(II)和 Cu(II)。结果表明，单分子的化学吸附是主要的重金属去除机制。在 298 K 下，通过单金属吸附等温线，最大吸附容量（mg·g）的排序为 Cu(II)（134.88）>Mn(II)（109.10）>Zn(II)（108.10）。此外，还通过傅里叶变换红外光谱、Brunauer-Emmett-Teller 方法、带有能量色散 X 射线光谱的扫描电子显微镜、X 射线衍射和 X 射线光电子能谱进行了特征分析。结果表明，离子交换可能是去除 Mn(II)和 Zn(II)的关键，而 C-O、O-H 和 C = O 可能通过络合或其他反应对 Cu(II)的去除起关键作用。
Zotero 插件