Study of Ionic Interactions in Seawater

海水中离子相互作用的研究

• 批准号: 9201739
• 负责人: Frank Millero
• 金额: $ 29.64万
• 依托单位: University of Miami
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1992
• 资助国家: 美国
• 起止时间: 1992-06-01 至 1995-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9201739&HistoricalAwards=false
• 关键词: Study; Ionic; Interactions; Seawater

Work is underway to examine how ionic interactions affect the rates of oxidation and reduction of metals and nonmetals in seawater. Measurements of the rates are being made in seawater as a function of pH, salinity, temperature and composition to elucidate the effect of the ionic components of seawater. Studies of the products and intermediates of the reactions will be made (when possible) in an attempt to elucidate the mechanisms of the reactions. Measurements are continuing on the oxidation of H2S with the oxides of Fe(III) and Mn(IV) in seawater as a function of pH, temperature, and salinity. The disappearance of H2S and the appearance of Mn(II) and Fe(II) are being measured. The effect of pH, temperature and salinity on S, HSn, SO32, and S2O32 is being studied The research includes completion of studies on the reduction of Cr(VI) with H2S and the reduction of Cu(II) with H2O2 in natural waters. Measurements of the stability constants of metals with HS will be continued using a square wave polarographic technique developed by Luther (Univ. of Delaware) that senses free HS at nM levels. New thermodynamic modelling will be carried out on the speciation of divalent and trivalent metals, the carbonate system and the state of Fe(II) and Fe(III) in seawater. These studies will hopefully lead to a consistent set of stability constants and Pitzer interaction parameters that can be used to characterize these systems in natural waters.

目前正在进行研究离子相互作用如何影响海水中金属和非金属的氧化和还原速率的工作。 测量海水中的速率与 pH、盐度、温度和成分的函数关系，以阐明海水离子成分的影响。 将（如果可能）对反应的产物和中间体进行研究，以试图阐明反应的机制。 正在继续测量海水中 H2S 与 Fe(III) 和 Mn(IV) 氧化物的氧化情况，作为 pH、温度和盐度的函数。 正在测量 H2S 的消失以及 Mn(II) 和 Fe(II) 的出现。 正在研究pH、温度和盐度对S、HSn、SO32 和S2O32 的影响。该研究包括完成在天然水中用H2S 还原Cr(VI) 和用H2O2 还原Cu(II) 的研究。 将继续使用 Luther（特拉华大学）开发的方波极谱技术来测量含 H2S 的金属的稳定常数，该技术可检测 nM 水平的游离 H2S。 新的热力学模型将针对二价和三价金属的形态、碳酸盐体系以及海水中 Fe(II) 和 Fe(III) 的状态进行。 这些研究有望产生一组一致的稳定性常数和皮策相互作用参数，可用于表征天然水域中的这些系统。