Abstract:

Tincal is widely used mineral in ceramic and metallurgy industries and raw material of borax production. It contains clay minerals and crystal water in the structure. Tincal, named as sodium tetraborate decahydrate, that has same formulation with borax, as known as borax decahydrate is the member of sodium borates and its formulation is expressed as Na2B4O7.10H2O or Na2(B4O5(OH)4).8H2O. Extra weight of water in raw boron minerals may become problem in point of transportation, storage, energy cost for producing anhydrous borates and by-product. In this study, with the aim of removing structural water and creating structural alterations for the forward mineral processing with less cost. High-energy ball milling, as known as mechanical activation process, was applied by planetary mono mill with variable parameters such as revolution per minute-speed of main disc (100, 200, 300, 400, 500 and 600 rpm for 30 min at ball-to-mass ratio 20), ball-to-mass ratio (10, 20, 30 and 40 for 30 min at 600 rpm) and mechanical activation time (15, 30, 60, 90 and 120 min). Investigations of effects of activations parameters were done by using X-ray diffraction analysis, Fourier transform infrared spectroscopy and thermal analysis. It was concluded that structure of tincal was changed and loss of crystalline water was occurred during high-energy ball milling. 

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