Electrochemical data concerning electrically conductive sulfide minerals submitted to high pressure hydrothermal fluids above 150 degrees C has not been reported in spite of its significance. In this work, electrochemical impedance spectroscopy (EIS) and Tafel studies of pyrite corrosion in pure water, 3.5% NaCl solution and 0.1 M sulfuric acid with 1796 kPa O-2 at 350 degrees C, 30 MPa were conducted, with the assistance of a self-designed three-electrode electrochemical measurement set-up that can operate in high pressure hydrothermal fluids. Results show that in pure water, 3.5% NaCl solution, and 0.1 M sulfuric acid with 1796 kPa O-2, corrosion potential (E-corr) is respectively -150, -334 and -752 mV, corrosion current (I-corr) is respectively 1.44E-5, 1.95E-4 and 7.73E-3 A. The solid-liquid interface information at pyrite surface achieved by EIS measurements reveals an important reason of the difference between the values of E-corr and I-corr in the three studied fluids. The electrochemical studies in this work also provide a promising method for research into the corrosion of other conductive sulfide minerals in high pressure hydrothermal fluids. Publication name | INTERNATIONAL JOURNAL OF ELECTROCHEMICAL SCIENCE, 12 (1):610-617; 10.20964/2017.01.11 JAN 2017 | Author(s) | Lin, Sen; Li, Heping; Cui, Can | Corresponding author(s) | LI Heping liheping@vip.gyig.ac.cn Chinese Acad Sci, Inst Geochem, Key Lab High Temp & High Pressure Study Earths In, Guiyang 550081, Peoples R China. | View here for the details
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