用KMnO4进行序列氧化过程:无氧沉积物中可变降解能力分量的成分特征
Xuemei Chen1, Zhijun Li2, Songjie Fu3
1Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China; University of Chinese Academy of Sciences, Beijing, 100049, China.
The Science of the total environment
|October 26, 2024
概括
这项研究开发了一种测量沉积物降解能力 (RC) 分数的方法,揭示了降解有机物 (ROS) 是主要的贡献者. 这种新的基于RC的指数提供了一种比传统的Eh测量更全面的方法来评估沉积物的氧化还原状态.
科学领域:
- 环境化学环境化学
- 水上地球化学 水上地球化学
- 沉积物学的沉积物学
背景情况:
- 沉积物中的降解物质对于沉积物-水界面的氧化还原状态和物质交换至关重要.
- 关于这些物质在水体沉积物中的丰度,形式和可降解性的知识有限.
研究的目的:
- 开发和应用基于pH依赖的KMnO4氧化能力的沉积物减少能力 (RC) 的顺序分成程序.
- 描述不同RC分数内的降解物质 (N_i) 的分子和每摩尔电子损失.
- 建立一个复合降解能力 (CRC) 指数,以更全面地评估沉积物的氧化还原状态.
主要方法:
- 用KMnO4的氧化能力将沉积物降解能力分成RCpH7.0和RCpH2.0的序列分成.
- 将分成方法应用于来自湖泊和水库的60个沉积物样本.
- 减少有机物质 (ROS),Fe (II) 和硫化物 (Sn) 对每个分量的贡献的表征.
主要成果:
- 平均RCpH7.0和RCpH2.0分数分别为45.4和42.8 cmol e·kg-1 DW,根据沉积物起源有显著的变化.
- 降解有机物 (ROS) 是这两种分量的主要贡献者 (68.0%的RCpH7.0和90.0%的RCpH2.0).
- 铁 (II) 是第二大贡献者,而硫化物 (Sn) 是次要成分,特别是在RCpH2.0分数中.
结论:
- 开发的RC分化方法有效量化了沉积物减少能力.
- 每个摩尔 (Ni) 丢失的电子数量在分数和沉积物类型之间有所不同,将ROS与Fe (III) 和硫化物相关联.
- 复合材料降解能力 (CRC) 指数提供了与Eh. Eh. Eh. Eh. Eh. Eh. 相比,沉积物的氧化还原状态的更详细描述.
相关概念视频
Redox Titration: Other Oxidizing and Reducing Agents
247
Besides iodine, other oxidizing or reducing agents can serve as titrants in redox titrations. Common oxidizing titrants include KMnO4, cerium(IV), and K2Cr2O7. The choice of oxidizing titrants depends on factors like stability, cost, analyte strength, and reaction rate between the analyte and titrant. KMnO4 is a strong oxidizing titrant that reduces from Mn(VII) to Mn(II) in a highly acidic solution, simultaneously oxidizing the analyte to a higher oxidation state. In this case, KMnO4 acts as a...
247
Metabolism of Chemolithotrophs
2
Chemolithotrophs are microorganisms that obtain energy by oxidizing inorganic molecules such as hydrogen gas (H₂), ammonia (NH₃), reduced sulfur compounds (H₂S, S²⁻), and ferrous iron (Fe²⁺). Unlike heterotrophic organisms that rely on organic carbon, chemolithotrophs transfer electrons from these inorganic donors to the electron transport chain (ETC), generating a proton motive force (PMF) that drives ATP synthesis through oxidative phosphorylation.
2
Oxidation of Phenols to Quinones
2.9K
In the presence of oxidizing agents, phenols are oxidized to quinones. Quinones can be easily reduced back to phenols using mild reducing agents. The electron-donating hydroxyl group enhances the reactivity of the aromatic ring, enabling oxidation of the ring even in the absence of an α hydrogen.
o-hydroxy phenols are oxidized to o-quinones and p-hydroxy phenols to p-quinones. Such redox reactions involve the transfer of two electrons and two protons. The reversible redox...
o-hydroxy phenols are oxidized to o-quinones and p-hydroxy phenols to p-quinones. Such redox reactions involve the transfer of two electrons and two protons. The reversible redox...
2.9K
Oxidation of Alkenes: Syn Dihydroxylation with Potassium Permanganate
11.0K
Alkenes can be dihydroxylated using potassium permanganate. The method encompasses the reaction of an alkene with a cold, dilute solution of potassium permanganate under basic conditions to form a cis-diol along with a brown precipitate of manganese dioxide.
11.0K
Oxidation and Reduction of Organic Molecules
6.2K
Energy production within a cell involves many coordinated chemical pathways. Most of these pathways are combinations of oxidation and reduction reactions, which occur at the same time. An oxidation reaction strips an electron from an atom in a compound, and the addition of this electron to another compound is a reduction reaction. Because oxidation and reduction usually occur together, these pairs of reactions are called redox reactions.
The removal of an electron from a molecule, results in a...
The removal of an electron from a molecule, results in a...
6.2K
Sample Preparation for Analysis: Advanced Techniques
301
Accurate analysis of complex samples often requires advanced preparation techniques to achieve reliable and reproducible results. Samples containing inorganic or organic materials can be challenging to dissolve or decompose effectively. Standard sample preparation methods include acid digestion, fusion, dry ashing, and wet digestion.
Acid digestion with strong acids is commonly used to dissolve inorganic materials that are insoluble (do not dissolve) in water. This method can be useful for...
Acid digestion with strong acids is commonly used to dissolve inorganic materials that are insoluble (do not dissolve) in water. This method can be useful for...
301


