Overlooked Formation of Carbonate Radical Anions in the Oxidation of Iron(II) by Oxygen in the Presence of Bicarbonate

被引:10
|
作者
Vijay, Aswin Kottapurath [1 ,2 ,3 ]
Sharma, Virender K. [4 ]
Meyerstein, Dan [1 ,2 ,3 ]
机构
[1] Ariel Univ, Dept Chem Sci, IL-40700 Ariel, Israel
[2] Ariel Univ, Rad Res Ctr, IL-40700 Ariel, Israel
[3] Ben Gurion Univ Negev, Chem Dept, IL-8410501 Beer Sheva, Israel
[4] Texas A&M Univ, Dept Environm & Occupat Hlth, College Stn, TX 77843 USA
关键词
Atmospheric Oxygen; Carbonate-Radical-Anion; Iron(II); Kinetics; Reactive Intermediate; FE(II); MECHANISM; KINETICS; DIOXIDE;
D O I
10.1002/anie.202309472
中图分类号
O6 [化学];
学科分类号
0703 ;
摘要
Iron(II), (Fe(H2O)(6)(2+), (Fe-II) participates in many reactions of natural and biological importance. It is critically important to understand the rates and the mechanism of Fe-II oxidation by dissolved molecular oxygen, O-2, under environmental conditions containing bicarbonate (HCO3-), which exists up to millimolar concentrations. In the absence and presence of HCO3-, the formation of reactive oxygen species (O-2(center dot-), H2O2, and HO*) in Fe-II oxidation by O-2 has been suggested. In contrast, our study demonstrates for the first time the rapid generation of carbonate radical anions (CO3 center dot-) in the oxidation of Fe-II by O-2 in the presence of bicarbonate, HCO3-. The rate of the formation of CO3 center dot- may be expressed as d[CO3 center dot-]/dt=[Fe-II[[O-2][HCO3-](2). The formation of reactive species was investigated using H-1 nuclear magnetic resonance (H-1 NMR) and gas chromatographic techniques. The study presented herein provides new insights into the reaction mechanism of Fe-II oxidation by O-2 in the presence of bicarbonate and highlights the importance of considering the formation of CO3 center dot- in the geochemical cycling of iron and carbon.
引用
收藏
页数:5
相关论文
共 50 条