identification and purification of montmorillonite mineral of ghaen mine bentonite

montmorillonite is the major mineral of bentonite with many applications in industrial fields but some impurities decreases the quality of the bentonite. the main objective of this study was to investigate the suitable method for purification of ghaen mine bentonite. a combination of methods was considered including wet sieving and sedimentation, centrifuge and ultrasound. the efficiency of purification methods was determined based on x-ray, particle size, cation exchange capacity (cec) and ratio peak of the quartz/montmorillonite analysis before and after experiments. the results showed that such methods were efficient for preparing of the materials having high quantity of montmorillonite with less than 2 microns particle sizes. cristobalite was the only mineral remained in samples, however many of particles were exempted from the samples. cristobalite was the main impurity remained with montmorillonite. chemical treatment is the only way for its complete removal. the results of this study revealed that by using easy, cheap and fast methods, it is possible for acceptable purification of bentonite.