Reduction of copper(II) by iron(II)

被引:54
作者
Matocha, CJ [1 ]
Karathanasis, AD [1 ]
Rakshit, S [1 ]
Wagner, KM [1 ]
机构
[1] Univ Kentucky, Dept Agron, Lexington, KY 40546 USA
关键词
D O I
10.2134/jeq2005.0002
中图分类号
X [环境科学、安全科学];
学科分类号
08 ; 0830 ;
摘要
Laboratory and field investigations have clearly demonstrated the important role of reduced iron (Fe(II)) in reductive transformations of first-row transition metal species. However, interactions of Fe(H) and copper (Cu) are not clearly understood. This study examined the reduction of Cu(H) by Fe(H) in stirred-batch experiments at pH 5.2 and 5.5 as influenced by chloride (Cl-) concentration (0.002-0.1 M), initial metal concentration (0.1-9.1 mM), and reaction time (1-60 min) under anoxic conditions. Reduction of Cu(II) to Cu(I) by dissolved Fe(II) was rapid under all experimental conditions and the stability of the products explains the driving force for the redox reaction. Under conditions of low [0-1] and high initial metal concentration, >40% of total Cu and Fe were removed from solution after I min, which accompanied formation of a brownish-red precipitate. X-ray diffraction (XRD) patterns of the precipitates revealed the presence of cuprite (Cu2O), a CUM mineral, based on d-spacings located at 0.248, 0.215, 0.151, and 0.129 nm. Fourier transform infrared (FTIR) spectroscopy corroborated XRD data for the presence of Cu2O with features located at 518, 625, and 698 cm(-1). Increasing [Cl-] stabilized the dissolved Cull) product against CU2O precipitation and resulted in more Fe precipitated from solution (relative to Cu) that appears to be present as poorly crystalline lepidocrocite (gamma-FeOOH). This process may be important in anoxic soil environments, where dissolved Fe(H) levels can accumulate.
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页码:1539 / 1546
页数:8
相关论文
共 53 条
[31]   SYNTHESIS AND STABILITIES OF THE BASIC COPPER(II) CHLORIDES ATACAMITE, PARATACAMITE AND BOTALLACKITE [J].
POLLARD, AM ;
THOMAS, RG ;
WILLIAMS, PA .
MINERALOGICAL MAGAZINE, 1989, 53 (373) :557-563
[33]  
RAI D, 1994, CONTAMINATION GROUND, P447
[34]   Fe(III) oxide reactivity toward biological versus chemical reduction [J].
Roden, EE .
ENVIRONMENTAL SCIENCE & TECHNOLOGY, 2003, 37 (07) :1319-1324
[35]   Electron transfer by copper centers [J].
Rorabacher, DB .
CHEMICAL REVIEWS, 2004, 104 (02) :651-697
[36]   Aspects of aqueous iron and manganese (II/III) self-exchange electron transfer reactions [J].
Rosso, KM ;
Smith, DMA ;
Dupuis, M .
JOURNAL OF PHYSICAL CHEMISTRY A, 2004, 108 (24) :5242-5248
[38]  
SCHECHER WD, 1998, MINEQL PLUS VERSION
[39]   IDENTIFICATION OF FERRIHYDRITE IN SOILS BY DISSOLUTION KINETICS, DIFFERENTIAL X-RAY-DIFFRACTION, AND MOSSBAUER-SPECTROSCOPY [J].
SCHWERTMANN, U ;
SCHULZE, DG ;
MURAD, E .
SOIL SCIENCE SOCIETY OF AMERICA JOURNAL, 1982, 46 (04) :869-875
[40]  
Schwertmann U., 1991, Iron oxides in the laboratory. preparation and characterization