Development and verification of a mathematical model for variations of the specific surface area of mineral powders during intensive milling

In order to describe temporal evolution of BET surface area of a mineral substance during an intensive milling process, a mathematical model in the form of S = a + b e− mt + c e– nt has been developed based on well-established phenomena in mechanical activation processes. Validity of the proposed model was verified by the results of experiments performed on a natural chalcopyrite mineral as well as those reported in the literature on a variety of sulfide minerals. It was shown that the model could fit different types of surface area variation with a very good accuracy.