Mechanochemical effects on the molybdenite roasting kinetics

The kinetics of molybdenite roasting was studied by non-isothermal TGA–DTA with heating rate 10 °C min−1. Mechanical activation of molybdenite was accomplished via milling in a planetary mill under air atmosphere. Mechanical activation decreased the ignition temperature of reaction from 470 to 180 °C after 36 h of milling. The model-fitting kinetic approach has been applied to TGA data. The reaction mechanism for non-activated molybdenite was determined to be chemically controlled with E = 34.25 kcal mol−1 and A = 2 × 108 s−1. In the activated molybdenite the reaction mechanism changed to diffusion control with E = 60.55 kcal mol−1 and A = 6 × 1019 s−1.