Mineralogical investigation and water absorption of bentonites in Momen Abad area, to be used in pelletizing industry and a comparison with some other bentonite mines in Eastern Iranian Bentonite Zone

Momen Abad Mining area is a part of the Eastern Iranian Bentonite Zone. Mineralogical studies revealed the presence of cristobalite and smectite as the main phases and plagioclase, feldspar and amorphous silica occur as the minor phases and this mineralogy favors the application of this mineral assemblage in pelletizing industry of iron concentrate. Scanning Electron Microscopy of bentonite clumps indicates that smectite clays show wavy sheet like morphology with overgrowth of cristobalite and bentonite sheet grains occur as aggregates with flocculated appearance and spherical and angular grains with popcorn texture. Based on the Na and Ca contents it was found out that the bentonites are compositionally Na members. Water absorption tests on 104 samples indicate that the Momen Abad samples from trenches shallower than 15m are not favorable for pelletizing however deeper samples show acceptable parameters for this purpose. In addition, the results obtained from comparison of eight mines indicate that Momen Abad and Deheshk mines with absorption of higher than 600 are more convenient than samples from Sanajan, Tighab, Khosh’hal, Ebrahimi, Mortezanejad, and Shirazi mines.