The kinetics and mechanism of the pyrite-to-pyrrhotite transformation

From: Metallurgical and Materials Transactions | Date: April 1, 1998| Author: | Copyright information

The kinetics of the transformation of pyrite to pyrrhotite have been investigated. The study was performed using thermogravimetric analysis over the temperature range of 620 to 973 K in atmospheres of H^sub 2^, He, Ar, and in vacuo over a wide range of pressures: 0.20 Pa to 4.24 MPa. Based on the kinetic results, a mechanistic picture of the various steps exerting control over the transformation is proposed. The thermal decomposition proceeds via a two-step, consecutive process. The ratecontrolling step is the desorption of sulfur vapor from the surface. The presence of H^sub 2^ introduces ...

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