Kinetics of the transpassive oxidation of pyrite. Technical progress report, July 1, 1992--October 20, 1992

Technical Report · Thu Dec 31 04:00:00 EST 1992

DOI:https://doi.org/10.2172/10128685· OSTI ID:10128685

Hu, Weibai; Huang, Qinping; Zhu, Ximeng; Li, Jun; Bodily, D M; Wadsworth, M E

In the transpassive region, about 0.4 to 0.8 V (SCE), aggressive oxidation of pyrite occurred. The reaction products in this region were Fe(III) oxide, sulfate ion and partially oxidized sulfur intermediates. The growth kinetics of the reaction of pyrite were studied using chronoamperometry measurement with both stationary and rotating disk electrodes. The effect of electrode rotation speed, solution pH and temperature were examined. Potentiostatic measurements were well correlated by a paralinear rate equation, suggesting the formation of an intermediate passive film, associated with the simultaneous dissolution of the outer layer of the film. Activation energies of 66.17 kJ/mole (15.83 kcal/mole) and 38.67 kJ/mole (9.25 kcal/mole) were obtained for associated parabolic and linear rate constants respectively, at an applied potential of 0.6 V.

• Research Organization: Utah Univ., Salt Lake City, UT (United States). Dept. of Metallurgical Engineering
• Sponsoring Organization: USDOE, Washington, DC (United States)
• DOE Contract Number: AC22-89PC89758
• OSTI ID: 10128685
• Report Number(s): DOE/PC/89758--T14; ON: DE93008180
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
010300
010600
ACTIVATION ENERGY
AMPEROMETRY
CHEMICAL REACTION KINETICS
IRON OXIDES
OXIDATION
PREPARATION
PROGRESS REPORT
PROPERTIES AND COMPOSITION
PYRITE
REACTION INTERMEDIATES